Wednesday, December 30, 2015

California finally catches a break? Updated 12/30/15

In the post I did on the 28th (read it here) I gave a wrap-up of the significant winter storm (that just happened to miss much of Kansas).   Look at the lack of snow...

I could blog about the specifics of the storm and what it did and didn't do and have a really, really long reading.  But I won't this time.

But I do want to remind everyone that weather systems are not a solid object that can be coherently tracked from one location to another.  Weather is NOT one dimensional and is NOT a solid, but rather is 3D (can argue it's actually 4D) and is a fluid that changes continually.  There are around 100 tredecillion (that is a 1 with 44 zeros) molecules that make up the atmosphere.  Computer forecast models attempt to track some of these molecules that are governed by such things as Newton's 2nd Law of Motion, the Ideal Gas Law, Equation of Vertical Motion, Equation of Continuity, First Law of Thermodynamics, etc, etc..  Expert Meteorologists are forced to absorb a torrent of information to make predictions as accurate as possible. That is dealing with a small fraction of the 2.5 quintillion bytes of information that is generated each day - the equivalent of the entire printed collection of the Library of Congress about 3 time per second.

Like a baseball umpire, a weather forecaster rarely gets credit for getting the call right.  So be it.

Go back to posts I did during the late fall.  I had concerns that the "El Nino" would not benefit California until later in the winter.  It looks like that is finally starting to happen.  I can argue that this past Christmas weekend storm could have been influenced heavily by the beginning of these changes. 

Looking at the afternoon satellite image...

The upper air flow has recently become chaotic.  There is still flow across the central U.S. with minor disturbances that will likely keep cloudiness across much of the area for a few more days.  There was a disturbance (the X across western Canada) that was dropping south that will intensify but should get cut off and meander around the NW U.S. for a while.  The reason it will cut off is the split in the jet stream that is developing (likely because of the strong south to north jetstream that has developed out of the tropics and into Alaska).

The significant changes

There is a new East Asian jetstream that has expanded across the Pacific, but this time much farther south!  The reason for this is a VERY robust Madden Julian Oscillation (MJO).  In fact, looking at a phase-space analysis of this MJO, it is 2 1/2 to 3 standard deviations above normal.  Unreal and significant!  Here is that chart...

At the same time the Arctic Oscillation is forecast to crash (maybe in the wake of the very temporary storm going through that region raising temperatures)?

So what does this all mean?

The nature of the weather pattern generated early this fall from different source regions forcing the jet stream into a cycling pattern, is set to favor the jet stream to dip into the western U.S. again.  The first evidence of this will be the East Asian jetstream that will bring a significant precipitation event to all of  California.  Look at the prediction from WPC...

This system will move out into the central and southern plains late in the weekend or first of next week, but will also be weakening as it does.  There could be a bit of light precipitation for the high plains but it should not be too significant.   I've been expecting a pretty strong storm sometime afternoon the first of the year for some time (centering on late in the first week).  With all the changes going on across the Pacific and with the timing of the pattern, there may very well be a decent storm somewhere around the 7th (give or take a few days).  Nothing is really showing up right now, but that may be changing.  I won't have a chance to post here until probably the 3rd or 4th, so check back then and I'll update on the prospects of the possible storm AND a turn to sharply colder by mid-month.

Monday, December 28, 2015

Update - 12/28/15

What a storm!  From an epic blizzard across eastern New Mexico and far west Texas, to an outbreak of killer tornadoes (at least one an EF4), to record breaking rainfall and extensive flooding!  And then, NOTHING for much of western Kansas and eastern Colorado!  If you have read this blog, or if you haven't (go back and read the past few posts), you will know how much uncertainty there was on the track of this particular storm.

The pattern had been set and an ocean/atmosphere forcing pattern was in place to produce an intense storm that was expected to occur between Christmas and the last few days of the month (I had discussed this several times during the past month).  Computer models started to "hint" at this possibility as early as December 12.  That really was no surprise.  But thanks to the internet, one individual chose to post this one specific solution and it went viral (indicating Dodge City would get 25.7 inches of snow, for instance), and was forever etched in the human mind.  Then for about a week the same computer model showed absolutely nothing, anywhere including West Texas. Again, not surprising as it (flip flopping) happens frequently.

As we got 3 days out, the computer models were showing that the storm would reach maximum intensity somewhere near El Paso and then move east and north from there.  The forecasting problems were many - where would it track, where would the surface response occur, how much cold air would be in place, what would the temperature profile be above the surface, etc., etc..  This particular system had an insane amount of boundary layer moisture to work with.  Low 70 dew points had moved into southeast Oklahoma.  For late December, that is almost unheard of!

When I provided a forecast, I told people that the range of possibilities (for southwest Kansas) were huge, ranging from several feet of snow to virtually nothing!  Why such a large range?  Because for this storm, it would have everything needed to produce an epic amount of snow and wind and could very well track into Kansas.  But at the same time, there was evidence that it would track too far south to produce much in western Kansas.  Even as of the 26th, there was still concern that it would be close enough.  In the post I did on the 26th (read it here), I showed two possible tracks (1 and 2). Obviously it took track #2.  Nobody should have a problem by preparing for a very high impact winter storm, that could have rivaled the January 1886 or the March 1957 blizzard.  The folks of eastern New Mexico and far West Texas probably have a different opinion compared to farther north.

I'm hearing reports that there are still stranded motorists on some roads of eastern New Mexico. Hopefully nobody died in the blizzard.

The following map shows how much precipitation has fallen the past few days.  Epic!

That is 10 to 15 inches of rain across eastern Oklahoma, Arkansas and Missouri!  That is extreme for any month, let alone December.  There may actually be some concern for the reservoirs in these areas being capable of controlling the massive runoff.

As of this morning, here is the satellite image of the storm.

The red dashed line is the track the upper system took...or the southern track.  Also, the storm ingested dry air from the north and made the impacts (as it moved out) a little smaller/tighter.  In the previous posting I discussed the "kicker" and that has dropped into central California as of this writing.

The "kicker" system will move into the plains later Tuesday or early Wednesday.  The system will be lacking moisture to work with but could still produce a small amount of precipitation (most likely snow) but it does not appear to be a big event at all.

Looking ahead into the first of the year, I've been expecting another storm not too far into the first of the year, but I'll have to analyze the situation once I get back to work.  Stay tuned for that one. Overall it should be an active January - and likely colder as well.

Saturday, December 26, 2015

Update 12/26/15 (time sensitive)

This post is time sensitive and will quickly become outdated due to the nature of the December storm that is impacting the central southern parts of the U.S..  Please rely on the National Weather Service for updated specifics for your area.  You will continue to see varying amounts of snow, ice, and rain amounts forecast by different entities (the media sure seems to enjoy this)!

The late afternoon radar showed a huge of rain and thunderstorms spreading north.

As has been expected, the "storm" has intensified into a tight upper level low as depicted by the satellite image from this Saturday afternoon.

There was a deep and moist fetch of air from the tropical regions into Texas and out across the midwest.  An INCREDIBLE amount of boundary layer moisture had moved north into southern Oklahoma.  Dew point temperatures had risen into the lower 70s as far as southeast Oklahoma.  This could be unprecedented for December 26.  As a result, copious amount of rain along with tornadic thunderstorms have already occurred and will continue to be a threat. The surface map following below shows where the front had ended up (north winds on the poleward side, south winds on the equator side of the boundary).

Back to the satellite image.  There is still some uncertainty of the eventual movement of the upper level low with the storm.  The system has not reached it's maximum intensity so could still change directions pretty easily.  Some of the computer guidance suggests that the low will track as depicted by #2 while a handful of other computer models suggest a track closer to #1.  This will have a huge impact on the eventual snow or ice across Kansas.  For west Texas and the panhandle and eastern New Mexico, it appears pretty certain that there will be a major blizzard.  Again, check for details for your specific area (click on the map that pops up).

Back to the track.  If the storm eventually turns more like track number 1, the snow amounts will ramp up farther northwest, perhaps into southeast Colorado.  If the track is more like number 2, the snow amounts, for say Dodge City, will be much, much less.  Again, check the NWS products for the details. There will also be heavy sleet on the east side of the snow area.

Another thing that is certain is the extremely high amounts of rainfall that is expected.  Look at the Weather Prediction Center forecast!  This is absolutely incredible for any month, let alone the last part of December.

Sleet and some snow will also spread into eastern Kansas as the storm departs on Monday.

I'll try and update again on Sunday or Monday.

Looking ahead, there could still be a weather maker just after the first of the year.  I'll try and nail down timing of this later in the week.  I've talked about that possibility in the blog several times now so it would fit the pattern.

Thursday, December 24, 2015

Quick update - 12/24/15

Please read the post I did yesterday (click here).

The "storm" is definitely intensifying as expected, but the eventual track and strength is unknown since it STILL was not over the CONUS where weather balloons would be able to sample the atmosphere.  What does this mean?  It means that specific details on the sensible weather that will occur across the plains and adjacent areas is absolutely impossible to nail down with any confidence!  For instance, if you are seeing specific amounts from different sources (the TV weather people are a prime example of this), then these specifics are nothing more than a wild guess.   I know it's hard to prepare for something unknown.  Maybe it's best just to plan for a worst-case-scenario.

Looking at the late afternoon satellite image (go back and compare to the satellite image from yesterday too)....there are several notable features.

X1 has undergone significant development since Wednesday (as was expected) and was becoming pretty intense.   It is this system that will cause the issues.  X2 has dropped south and has pumped up the ridge (blue line) that has contributed to the development of X1.  Now there is an X3 that will become a player.  Let me explain.

X1 will continue to undergo development and become an intense upper low.  There remains a huge question mark about how far south it will go before turning east.  If it turns east too far south, it will keep major winter precipitation out of eastern Colorado and western Kansas and limit the white chaos to areas of eastern New Mexico and west Texas.  If it turns northeast, then much of the high plains will get clobbered and this could extend into other parts of Oklahoma and Kansas.  X3 will be the mechanism that "could" force X1 to turn more northerly.  Confused? 

Bottom line...the most favored area for heavy snow (and likely blizzard conditions) for late in the weekend is probably from near Lubbock to Amarillo and into far western Oklahoma.  But, areas farther north CANNOT be ruled out yet because the eventual track is still unknown.  By late Christmas morning or early afternoon, the situation "should" become a bit clearer.  I might have time to do a quick update, but it's best to just rely on information out of the National Weather Service.

One final bit of info...this system will cause extreme rainfall in the warm sector.  Look at the precipitation map from the Weather Prediction Center. WOW!  There will be major flooding in those areas that receive the extreme rain amounts.

Wednesday, December 23, 2015

Update about the "storm"

Please review the previous post I did on Monday to give you a sense what we're dealing with on this upcoming winter storm.  You can read that post by clicking here.

Unfortunately there are STILL many possibilities with the outcome of this weekend/early week storm.  The main reason is that the storm isn't even a storm yet.  Look at this afternoons satellite image.

The evolution of this potential major winter storm will be VERY complicated!  As of Wednesday afternoon it was only small upper level system over the Gulf of Alaska.  On the satellite image it is denoted by the X1.  The key will be upstream!  There was a deep upper system (denoted by the X2) that was forcing "warm" air north across the Aleutians.  We call this upper level ridging.   This ridging was also phased with ridging along the dashed line extending southeast.  Both the X2 system and this subsequent ridging is directly tied to the MJO that I talked about in the previous post!

X1 will undergo significant development as it dives southeast and again the influences from X2 and it's ridging will determine this eventual development.  If X1 was over the CONUS it would be sampled by weather balloons and I would have a better idea of the this development.

So, as of now (Wednesday afternoon), there are still many, many questions and uncertainties.  It is unclear just how far south this storm will "dig" and then just how far it will get east before eventually  turning north.  Computer forecast models during the past 24 hours have been trending for a track  from northern Mexico to southeast Oklahoma (which is shifting south).  Because of the numerous questions and uncertainties, there really is just no way to get specific about the outcome of the sensible weather.  The range of possibilities is still very large!  But it is looking more likely that much of the precipitation from the eastern Texas Panhandle to central Kansas may fall as sleet or a mixture of sleet and freezing rain which will limit snow amounts.  It's impossible to say where the transition line from rain to sleet/freezing rain to snow will set up.  For NW KS there may be a nothing at all to some snow.  If this system does indeed move farther south, then the heaviest winter precipitation will be limited to the panhandle into central Kansas.  It could even end up being a huge sleet storm too!

The only advice I have at this point is just be prepared and pay close attention to the forecasts and statements that will be issued by the National Weather Service.  The TV stations and Facebook posts will continue to show the output from various forecast models and the output from them will change, perhaps dramatically every six hours.

I do feel confident that travel will become very treacherous from west Texas into central Kansas by Sunday/Monday and perhaps as early as Saturday night.  I'll try and update again sometime Thursday.

Monday, December 21, 2015

The STORM - here we go! Updated 12/21/15

On the 16th I blogged about a viral Facebook post that was circulating throughout the land.  You can read that discussion herePLEASE do read that discussion as I talked about computer models that attempt to forecast weather elements from 1 to 384 hours (and in some cases longer).

In that blog post I also discussed THE referenced graphic of the epic snowstorm that could occur on the 28th.  Since that time this same computer model has forecast absolutely nothing, rain, sleet and snow and anywhere from east central OK, central Texas to Nebraska.  It's a common occurrence for this to happen.  IF that particular model run would verify, it would do so by only dumb luck.  This person on Facebook that posted this model output has since shown almost every other output solution., except for the ones that showed nothing.  Remember, these forecast models will sometimes fail within the first 12 hours, let along 324 hours in the future!  But, sometimes (rarely) they can be close!

Also in that posting I did, you may recall that I said "ironically there could very well be a storm between Christmas and the last few days of December".  The pattern and current atmospheric forcing would lead me to believe the possibility.  That still does appear to be the case!

First, leading up to this "STORM".

In this afternoons satellite image, there were two features that may impact part of the plains states.

The first feature is the X1 over Washington...that feature is going to move rapidly south and east and could bring a few sprinkles to Kansas and Nebraska on Tuesday and snow to the northern Plains. The second feature, the X2, will dive into the plains by Wednesday and will bring additional light precipitation (mostly sprinkles) to the high plains but will become a strong storm for the midwest (liquid) and severe thunderstorms across the lower Mississippi Valley, including the possibility of tornadoes. 

Then attention turns to the STORM.  So, why did I say ironically there could be a storm after Christmas? 

First, the cycling pattern supports the jetstream diving into the Rockies at about that time (I've talked about these cycling patterns numerous times in this blog).  Second, the ocean temperatures and the location of tropical convection (forcing) also supports this diving, or digging, jetstream.

The Madden Julian Oscillation (MJO) supports this eventual transition.  The image below is what is called an MJO composite (there are different phases spaces that can be calculated)...

The transition from phase space 5 into phase space 6 for this time of year supports a trough of low pressure aloft located across the western U.S..

Looking at the satellite image from this afternoon...

The MJO was located across the Maritime Continents.  There was already a coherent response in the from of mirrored upper level flow (both northern and southern hemispheres).  The northern hemisphere flow was enhancing the "East Asian Jetstream" (the green line coming off eastern Asia).  The possible storm that could occur after Christmas was nothing more than a disturbed area in the flow aloft, marked by the X.

So what this means, is that this "X" certainly has the support from tropical forcing and extended East Asian Jetstream to "dig" into the western U.S. or Rockies by the weekend.  But, since this is still many days away, there is just no way to know exactly where the system will end up and how strong it will be.  But everything does support a vigorous storm, anywhere from south Texas to Nebraska.

The Global Forecast System ensemble forecast from this morning shows many possibilities by late Sunday.  Remember from my previous post, an ensemble forecast is attained by the computer model running with slightly different initial conditions.


What the above map shows is that there is still a huge range of possibilities for the position of the storm.  The black outlined light-green/grayed-in circle shows the composite (or average).   As we get closer to the event, I will have more confidence on what to go with.  The gulf of Mexico is very moist and warm and this system will have copious moisture to work with.  I'm very, very confident of flooding rains will occur across parts of eastern Texas, Oklahoma and the lower Mississippi Valley.  Depending on the track and evolution, heavy and flooding rains "could" also occur in Kansas and then the frozen stuff that will fall in the cold sector of the storm as the potential to be heavy.  Again, I'll get a little more specific as time approaches (I'll try and update later Wednesday or early Christmas Eve).  Follow for updates (some offices are starting to talk about it).

Wednesday, December 16, 2015

Update - December 16, 2015 - Viral social media posts

In the post I did on the 8th (click here), I mentioned how computer forecast models, that attempt to predict various weather elements, often fail even 12 to 24 hours out.  By changing initial conditions (perhaps temperatures) just a tiny bit, there are often huge differences several days out.  These models are run with these different initial conditions to come up with what we call ensemble forecast solutions.  Often, 5 to 10 days out these different ensemble solutions overlaid on a map look like spaghetti. The following is an ensemble of 20 solutions at 384 hours out using 20 different initial conditions:


What the map shows is that 16 days out, the jet stream configuration could be just about anything. Each different possibility was arrived at by plugging in an initial condition with a small difference.  Essentially what this tells us is that computer forecast guidance that far into the future cannot account for small changes in those initial conditions and should not be used for decision making.  Often the "control" output or solution is plotted instead of the ensemble members.

That "control" solution often changes from run-to-run (computer forecast is generated every six hours), especially in the later periods.  It's nothing new, this has been going on since models have been developed.

Unfortunately, because of the access of this output via the internet and because of social media, these varying solutions can be posted and often are posted.  Take for instance what occurred Tuesday, December 15.  A person on Facebook (his page name is Oklahoma Weather Network) posted output from just ONE computer run from the Global Forecast System (GFS), which has a tendency of exaggerating output elements.  The solution was "off the charts" and he posted it as if it might really happen.  The post has gone viral being shared (as of the 16th) over 10,500 times and likely reaching 100's of thousands of unsuspecting persons.  I've been answering a bunch of e-mails, Facebook posts and text messages inquiring about this "storm".

The following should shed some light on what we're dealing with:

First - the "solution" at 324 hours out valid for 12 PM Monday, December 28 that went viral:


When the same computer model was run 12 hours later the solution for the date was completely different!

Then, it was run 12 hours later and now look!  NOT A BIT OF SNOW!

This is a common occurrence with these long range models!

If you have followed my blog, you know that I look for a cyclic pattern and look for areas of forcing (areas of latent heat releases from the oceans and others) to produce these weather patterns.  I'm close to nailing down the cycle length (48 to 52 days I think) but with intermediate cycles embedded in the overall pattern.  Using this information, there actually "could" be a storm around the 28th.  More on that at the end of this post.

December 12-13 storm

Several posts ago I discussed changes in the pattern that would favor storminess starting as early as December 12.  Due to personal obligations (nothing big - just a daughter getting married :-)) I didn't have time to post anything specific.  As you are aware the storm that impacted the center of the country on the 12th and 13th brought a variety of weather.  There was even one tornado reported in the Texas Panhandle!  The amount of rainfall with the storm was epic for December and I saw a couple of 5 inch amounts in central and north central Kansas!

The snowfall was limited to elevation and the temperature profile.  Had the temperatures been just 3 to 4 degrees colder there would have been over 2 feet of snow in some locations!  In Dodge City there was 8 to 9 inches and if the temperature had been just a degree colder and a little sooner there would have easily been 12 to 15 inches!  What a storm!  The following is the snowfall map and a map of the water equivalent or rainfall:


There are areas of southwest Kansas that have recorded over 40 inches of precipitation since the first of the year!  Unreal!  Parts of southeast Oklahoma and northeast Texas are approaching 90 inches for the year!

Here is the latest satellite image:

The green lines/arrows represent the jetstream.  This is actually a-typical of an El Nino!  The strongest and most moisture laden stream of air is slamming into the Pacific Northwest while a typical pattern would be pointed towards California.  I talked about this for months in this blog and to me it's not surprising.  (I still see it possibly changing over the winter).

This afternoon there was a small disturbance over Idaho (not depicted on the satellite map).  It will move southeast and head rapidly towards the central plains  early Thursday and should help to bring more snow to Colorado and perhaps a little bit to western Kansas.  It shouldn't amount to a lot.

There are other systems across the Pacific.  With the cycling pattern, I do see at least a small chance of a minor system around Christmas that could bring some rain or snow to the region.  The bigger storm may be between Christmas and the last days of December.  Then based on the pattern, an even bigger storm could occur the first week of January followed by a "brief" Arctic outbreak.

I'll try and nail down specifics in the next post that I hope to do this weekend or early next week.

Tuesday, December 8, 2015

Update 12/8/15

I'm a little preoccupied at the moment with my daughter getting married this weekend, so this post will be somewhat brief.

In the previous post I did on the 3rd (read it here) in the outlook portion, I said "starting around December 12 and persisting for a week or two, the weather pattern will get active and likely stormy across much of the western and central U.S."Those changes are on track and have been showing up recently on computer forecast models with numerous differences in spatial and temporal solutions.   Here in lies the problem...

There are several global long range computer forecast models.  Most are run every 6 hours with output to many weeks into the future.  The more notable are the GFS and the ECMWF (but there are others).  Many times these (and shorter range models) have numerous errors in the output (forecast elements) and as early as 12-24 hours out!  By 4 or 5 days out these solutions are completely wrong!  It is challenging to forecasters in determining what may or may not be right.

To give an example, the following two images are snowfall for a 48 hour period ending December 18th.  The first had a large area of heavy snow across Kansas.  Just 6 hours later when the same computer model processed data, the solution for the exact same time had absolutely nothing!


This is a common theme with forecast models, especially many days out.  Every 6 hours there typically is a large difference in many elements.

Over the next few days and more, you are going to see and hear of "rumors" of storms or no storms.  Many sources of weather you will see on the internet are often going to post this output, as if it is gospel truth!  For example, go to Accuweather.  Look at specific forecasts in the future.  Check back often and notice the changes for specific days.  Why is this?  Because they typically just post this computer model output.  Many others do the same (The Weather Channel for instance).

What I do is try to look for trends and find repeating patterns and then give the most likely solution.  At this point, since I've been wrapped up in personal issues, I don't have a really confident idea.  But as I stated in the December 3 post, I was and still do expect changes lending to unsettled weather.  From this weekend and for at least 2 weeks (perhaps even longer) there should be quite a few storms across the middle of the country.  Look for a turn to wetter and often colder weather.  Once I get past the wedding (and recover lol), I'll try and pin it down.  Enjoy the rest of this mild December week!

Thursday, December 3, 2015

Update - 12/3/2015

It's been really busy for me personally - thus the gap in postings.

In the last entry I did (read it here) I discussed the well advertised "Thanksgiving storm".   In the end, the freezing precipitation got farther east and south than originally expected.  Major accumulations of ice were noted at many locations across Oklahoma and Kansas.  Liquid, freezing and frozen precipitation amounts were record breakers at some observation sites.  As the storm system finally lifted out of the Rockies and across the midwest, it brought heavy snows to the upper midwest.  All told, the storm system brought copious amounts of moisture.  Here is the estimated precipitation map:

Parts of southeast Oklahoma and northeast Texas are approaching 85 inches of precipitation for the year!  Unreal!

What's next?

In previous posts at various times this past year, I have discussed the weather pattern that establishes in the fall and persists well into the following summer.   I encourage you to go back through some of those postings to get an idea of what I'm faced with in determining the pattern.  Unfortunately, I still don't have a clear and obvious signal, but it's getting closer.  There are apparently intermediate harmonics that formed and which may contribute to a great deal of active weather this winter and following spring.  So the cycle length this year may be as short as 26 to 29 days or as much as 52-58 days.  Hopefully I'll know more in a couple of weeks.

But, regardless, I'm seeing enough evidence from the current upper level pattern and jet stream orientation across the Pacific that it may get pretty active again in 10 days or so.  More on the outlook in a bit.

Looking at the eastern satellite image (looking west) from this morning...

The first item that strikes me is the moisture laden air across the northwest U.S. as a strong system approaches that area.  Extreme amounts of precipitation will fall in that region of the country and southwest Canada through the rest of the week.  Higher elevations will get clobbered by many feet of snow.  If you have been following this blog, you know that during an El Nino this should not be happening!  All the precipitation should be south.  That is why I ALWAYS rely on what really goes on with the atmosphere and not just basing it on an El Nino event.  I think for now the above normal sea surface temperatures that had been across the northern Pacific basin and off the southwest U.S. coast may have a part in this.  But, this type of event should change as we get deeper into winter, i.e., eventually shifting south.

The other thing that has my attention is the jet stream from central Mexico into the southeast U.S..  It has shifted quite a ways east for an El Nino pattern (but will also shift back west, I believe).

Here is a look at the western satellite...


The "X" just west of California will move across the central plains early this weekend but the atmosphere will be too dry to support any precipitation, other than a sprinkle or two.  But as it gets into the Mississippi Valley it will become a decent storm.  And even stronger as it rides up the east coast.

The "L" in the Gulf of Alaska will be a major storm for that region.  The other "L" near the tip of the Aleutian islands  should bring addition rain and snow to the northwest.  Once this system gets to the northwest U.S., it may amplify, IF, the western Pacific behaves as expected.  The jet stream across the Pacific basin will become extended and perturbations flowing along should finally help the jet stream amplify across the western U.S.  The most likely time for this to happen will be towards the end of next week or weekend.  But, there are WAY TOO MANY uncertainties to get specific about any particular event.  I think it's safe to say though, at this point, is that starting around December 12 and persisting for a week or two, the weather pattern will get active and likely stormy across much of the western and central U.S..  I will put this out there...I would not be too surprised to see an outbreak of severe thunderstorms by mid-month (or a little sooner) that could be as far west as eastern Kansas and eastern Oklahoma!  Could we have another December tornado in Kansas like what occurred in Harper County on December 14, 2014?  I'm not saying it will happen (would be extremely rare), it's just something that is in the back of my mind.

Until then, "mild" and dry weather can be expected across the high plains for at least a week or more.

Tuesday, November 24, 2015

Thanksgiving storm update - 11/24/15

On Saturday I had an extensive post about last weeks severe weather and an outlook for the "Thanksgiving" storm.  You can read that long post here.  At the end of that post I discussed the upcoming storm.

In that previous post I showed a satellite image with  three features that were going to impact the plains weather.  The first was a low pressure system aloft (labeled L on the previous satellite image) and talked about how it would weaken as it moved south and then east and eventually into the plains.  Today that system had reached the southern Rockies and as expected was contributing to bringing Gulf Of Mexico moisture northward.  This moisture will translate into low clouds, some fog and drizzle later Tuesday night and Wednesday across a large part of Texas, Oklahoma and eastern Kansas.

Here is the latest satellite image as of Tuesday afternoon...(edit on image below - Sandra, not Rick)

Referring back to the satellite image I showed on Saturday....The original "L" is now the "X" over southern Colorado.  The original X1 is now the strong Low off the NW Coast.  The original X2 has moved to north of Hawaii but will likely still be a play maker for the plains (more on that at the end of the post).

More importantly is the storm, the one off the NW coast.  Again, in the previous post I showed the X with the superscript 1 on the satellite image.  At the time it was just a disturbance but as advertised it has since amplified into a power upper storm just off the Washington coast.  It will continue to drop south and become a big upper low over the Great Basin.  The strong jest stream on the west side will eventually translate around and lift out across the plains Wednesday night and Thursday.  The result will be a strong cold front dropping south into the plains and copious amounts of precipitation developing across the region.

The six million dollar question is just in what form will the precipitation fall.  The upper low has not been fully sampled yet by the National Weather Service observation  program as the storm was still off the coast.  But it has become increasing apparent that there will be mixture of precipitation as there will likely be a warm layer aloft with the storm.  The best guess, keeping in mind the limited sampling in the upper parts of the atmosphere, is the following for Thanksgiving Day and Friday...

The freezing precipitation will likely transition from west to east and this map illustrates perhaps the farthest east.  In other words, it will start as rain in areas like Amarillo, Dodge City, Wichita, Topeka, KC, Lincoln (etc.) and then flip to freezing precipitation later Thanksgiving or Friday.  It should remain all liquid across SE KS and most of Oklahoma.

What's my confidence?  Not that high, at least initially.

Snow amounts?  You're going to here everything because the media likes to use computer forecasting models that sometimes just are not capable of modeling the true atmosphere.  I've already heard 6 to 8 inches for Dodge City, yet there is a strong possibility that it may not even flip to snow until late in the storm.  What I'm saying is that it is WAY TOO EARLY to discuss amounts of snow and exactly where the snow will fall.

Here's the kicker....what about the X2 out in the Pacific?  Chances are pretty high that the upper low that forms out west may sit there for a number of days.  Eventually the X2 system will be ingested into the Great Basin storm and will be "kicked out" across the plains.  The most likely time for this will be late in the weekend.  It too should bring additional precipitation and I'm guessing the frozen line will be a bit farther south and east, but details are highly uncertain, if not impossible to say for sure.

Finally, what about Tropical Storm Rick Sandra that is in the bottom of the satellite image?  It will likely become a hurricane as it turns north.  Eventually the remnants will track  northeast and perhaps into Texas and the lower Mississippi Valley.  That will definitely have to be watched as there is a scenario that it would bring extensive flooding rains to that part of the country.  It's not entirely out the question that those remnants could be even farther north!  It'll have to be watched!

The Weather Prediction Center has the following outlook for precipitation through Sunday.   Impressive for anytime of the year, let alone the last part of November!

Stay informed by monitoring NWS forecasts at  If you're going to be on the road later this week and weekend, you can go to each states road reports web page.  A quick map to each state's DOT can be found here.

In Kansas you can go to: 

I will not be able to update this post until perhaps the weekend.

Saturday, November 21, 2015

Tornado Outbreak - Thanksgiving - Updated 11/21/15

The past seven days since I updated this blog were mind boggling for me, as a Meteorologist, and I'm sure for a lot of you.  I intended to update before now, but it's been a bit crazy.  If you missed the post I did a week ago, it can be found here.  In that post, I discussed the MAJOR storm that was going to impact the central part of the country.  Let me start with the tornado outbreak.

As far back as records go, the severe storms with numerous tornadoes was a historic event, especially for the area west of about 98 degrees west longitude.  Not all tornado tracks have been calculated yet, nor the number, but so far it looks like at least 3 dozen occurred!  Unreal for this late in the fall! 

But, let me just put this out there.  The tornado events were NOT the result of El Nino!  If you go back a few posts, you will understand why.  First, El Nino is not a "thing" or object that causes storms on a very small scale (such as tornadoes).  Second, the atmospheric flow aloft (jet stream) has NOT responded yet to the warm event in the Pacific (El Nino).  

The more important features could be the relatively warm waters of the North Pacific interacting with the MJO (have discussed this already), and the rapid cooling of the northern latitudes at the surface. The result caused the vigorous upper storm to dig into the southern Rockies (that is not a rare occurrence).  There was a leading "weak" upper system that came out of the southern branch of the westerlies that helped to draw moisture northward out of the Gulf but at the same time was weak enough that there was not a cold front behind it as it departed.  Then this vigorous upper system produced a tremendous jet stream that moved out across the plains (again, not a rare event). Everything came together just right to produce the supercell thunderstorms and resulting tornadoes. These specific type of setups have occurred before (not many), but this time all the necessary ingredients combined to produce the severe weather including the tornadoes.

The following are maps showing the tracks of most of the tornadoes that occurred...(click for a larger image)

I've been a professional Meteorologist for 32+ years and this is the first time in my career that I have been concerned for myself and my families safety once the tornadic supercell developed near Liberal, KS.  I was not at work but was able to interrogate the storm using radar software from home.  I knew the tornado that developed with that storm was large and potentially violent, especially considering it intensified after sunset (one reason is the nocturnal jet that forms after dark).  The track was consistent and it became increasingly apparent that Dodge City was in the potential path.  What made it worse, for me personally, is that the track was consistently right at my house!  Plus, the storm was showing absolutely NO change in intensity which was very concerning.  I got extremely nervous and actually a little sick to my stomach because I knew if the trend continued there would be tremendous destruction and a high potential for loss of life.  Visions were running through my mind of my personal belongings being scattered to other parts of Kansas.  I didn't feel a threat for my families safety though as I'm fortunate to have adequate shelter from these types of events. Wow, my cell phone about burnt up from the constant calls and text messages.  It was intense!

Here is a map showing the potential track (red line). 

BTW, this would have also been right across the Boothill Casino and the Dodge City High School.

Fortunately for Dodge City, the storm finally cycled and the original tornado weakened and turned north before dissipating, but not before travelling an astonishing 51 miles!  I might add that at it's largest size, the tornado was 1.1 miles wide with winds varying from 100 to 155 MPH!  Over a mile wide...think about that!

A second smaller and weaker tornado developed as the first was dissipating and fortunately (again for Dodge City) it turned immediately north.  

In addition, look at how fortunate Kismet and Plains were!  The two towns were blessed in a way. The original track would have taken the tornado right over both communities!

One final bit of information on these tornadoes.  The track and size of the tornadoes from Liberal were almost identical to what happened May 26 of this year!  The only difference was as the storm approached Dodge City in that event, the tornadoes turned to the right instead of the left and spared the city!

So, after the severe weather outbreak, the following day was greeted with a major snow storm!  The heaviest snow fell in a band from northwest Kansas into southeast Colorado.  The largest amount I saw was near Colby where around 20 inches fell!  This morning (Saturday the 21st), the band of snow still on the ground was very evident.

The storm that produced the severe thunderstorms and snow, also brought quite a bit of precipitation. Here is a map showing the estimated amounts for the past seven days.

Doing the damage assessment survey of the tornadoes, I saw a fair amount of milo that had not been harvested yet.  Unfortunately, most of it was sitting in standing water and likely will not be cut until the ground freezes later this winter.  I discussed this possibility in the previous post.

The earthquake on the third day?  I'm a Meteorologist, not a Geologist LOL.  It was the first time that I have been aware as it happened.  I was awoken by items rattling on the walls. 

In that post I did a week ago I mentioned the potential storm for Thanksgiving week.  Wouldn't you know, the potential is growing!  I won't go into too many details just yet (and I will do my best to update this Monday or Tuesday).

The latest satellite image from this morning...

This is a busy and very complicated satellite image showing numerous contributors for this weeks weather.  

First, the "L" off the west coast.  It is moving south and will eventually weaken and move across the central U.S. sometime Tuesday.  It may be just strong enough to bring some showers, but more importantly it will help to bring Gulf moisture back north.  

Second, look at the bottom right.  That is Tropical Storm Rick.  It, if it gets picked up by the jet stream, could potentially bring excessive rains to parts of Texas or lower Mississippi Valley.  

The most important feature is the X labeled with the 1 (Thanksgiving system).  It is really just a minor disturbance at this point but is expected to amplify and intensify into the first of the week.  The second X (labeled with 2) will also impact the pattern but at this point I'm not confident on it's interaction.  There are numerous possibilities at this point.  Once the X (#1) begins the amplification process I should have a better idea of all the developments.

At this point, the most likely solution, would be a major snow storm for the northern and central Rockies and out into the adjacent plains and perhaps as far as northwest Kansas.  Rain and thunderstorms will become increasing likely elsewhere.  All this would occur, most likely, up to Thanksgiving day.  The end of the week and into the weekend would be followed by MUCH colder temperatures with areas of the northern plains down into Nebraska potentially staying in the single digits for highs.   Details are highly uncertain so check back Monday or Tuesday.  Stay up-to-date by checking

A first guess at the amount of precipitation that "may" fall through the end of the week...

Again, details are highly uncertain so check back Monday or Tuesday.

Saturday, November 14, 2015

Update 11/14/15 - MAJOR storm

In the post I did on the 11th (click here) I discussed the vigorous storm lifting out of Kansas (which brought a "mini" blizzard and eventually severe weather including tornadoes to the midwest).  This system was the first intense development of the fall season.  Also in the post I talked about the Madden Julian Oscillation (MJO) and the impacts it was going to have and was having on the jetstream and a possible storm for the first of the week.

Updating that situation...indeed it looks as amplification is taking place in the winds aloft.  Looking at the satellite image from this Saturday afternoon....

The extended jetstream from the MJO is pointing towards southern California in the image.  Upstream, nearer the MJO, the Rosby wavetrain energy propagation was forcing strong riding of the flow across the Pacific basin.  This in turn is causing the significant deepening of the storm (#2 on the image) that will impact the plains this week.  Before I discuss that storm further, look at the "little" system (#1) on the image south of the Four Corners region.

This little storm, number 1, was helping to increase flow across Texas bringing increasing clouds and humidity.  Showers and thunderstorms will be increasing across Oklahoma and Texas, especially Sunday and some of this will move into Kansas (especially south central and eastern Kansas).

Back to the more important feature, #2.  There is still a tremendous amount of uncertainty of the magnitude and placement of this system as it drops into the Rockies and movement into the plains.  The possibilities are numerous.  There is no sense in getting specific at this point.  But, what is certain is that this storm will be intense with the likelihood of  severe thunderstorms, heavy rain, lots of wind and most likely heavy snow.  The "where" is just plain impossible to nail down, at this point in time.  But here are some educated "guesses"..

Severe weather early (Monday)...from the Storm Prediction Center

The severe risk for Tuesday will shift south and east.

As far as precipitation from this storm for Tuesday and Wednesday, here is an educated guess from my office...NWS Dodge City

Regardless of where everything sets up, I think there is a very high probability of precipitation that WILL impact harvesting of any residual crops across the plains. I hope those that need to get corn and milo out of the field are doing so this weekend.

I'll try and update this Monday to get more specific, hopefully.

Beyond this system, it looks like a much colder pattern is setting up towards next weekend and into Thanksgiving week.

Wednesday, November 11, 2015

Update - November 11, 2015

Just a quick update.  See the previous post here

The Fall pattern is getting cranked up, finally.  The first major "cyclone" to impact the central U.S. was lifting rapidly out of Kansas this Wednesday afternoon.  Blizzard conditions were observed for a time across northeast Colorado, far northwest Kansas and into Nebraska.  The visible satellite image was impressive this morning showing the typical comma shaped pattern associated with deepening mid latitude systems.  (click for a larger version).

In the "warm" sector ahead of the storm there had been a few reports of tornadoes, a couple of hail reports and a lot of wind damage reports from thunderstorm gusts.  This type of system will likely repeat again this winter and then again in the spring and early summer.  I should get an idea of a general time frame for this to happen in two to three weeks, so stay tuned.

The jet stream (strongest winds aloft) will continue strengthening and storm systems will begin to amplify more readily across the U.S..  Currently I'm watching a Madden Julian Oscillation (MJO) out over the Pacific.  I've talked about the MJO numerous times in this blog.  There is currently an awesome response from this MJO as it continues tracking very slowly east/east southeast.

Energy is being transported poleward (mirrored in both hemispheres) and it will eventually allow the Pacific jetstream to expand eastward into the western part of the country.  This should serve to help systems amplify across the west which will then impact the plains.

First up will be a potential precipitation maker late Monday into perhaps Wednesday.  There have been a few computer forecast models that have had this depicted to varying strengths.  If this does develop, then there will likely be another behind it toward the following weekend.  I'll try and update about these two systems and their developments sometime this weekend.

Thursday, November 5, 2015

Thunderstorms in November & CoCoRaHS - quick update 11/5/15

See the previous detailed post I did yesterday by clicking here.

In that post I gave an outlook into next week.

There was a narrow band of thunderstorms that swept across much of Kansas yesterday evening.  Here is a map showing the rainfall...(click for a larger version)

The rainfall was highly variable with some areas getting nothing or very little and others getting over an inch.    Rainfall maps like the one above can be made much more accurate if we had more observations.  One way is to ingest observations of rain gauge amounts through  a program that was started back in 1998.  That program is CoCoRaHS.

Events like last night, with the highly variable amounts that fell,  could be more easily verified if we had more reports.  Look, for instance at Ford County, KS.

Radar data was used heavily in generating the rainfall map but that radar data also ingested reports from CoCoRaHS to verify what the radar was calculating.  The CoCoRaHS program is an extremely important part of the observing program.  I talked with a few folks in Ford county that had 3/4 to 1 inch.  Please consider joining!

Wednesday, November 4, 2015

Update - 11/4/15

In the post I did on the 29th (read it here), much of the discussion was about the "Halloween" storm that had been discussed about in previous posts.  In that last entry, I showed a map of expected precipitation.  Here is that map..

and here is a map showing the precipitation that ended yesterday...(click for a larger version).

That was a pretty good forecast from WPC!

I also posted a map of the expected jet stream position for today (the 4th) and highlighted the unseasonably mild conditions with a chance for thunderstorms and where snow might fall this week.

Here is that forecast map from last week...

Here is the latest satellite image from this afternoon....
So far that forecast from last week is panning out perfectly!  There is currently heavy snow in the Rockies and the afternoon's temperatures are certainly mild for early November.

With the recent precipitation and with these mild temperatures it sure appears as if the Winter Wheat is making rapid Fall growth!  I'm only guessing, but is there now going to be a problem with green bugs?  A widespread hard freeze is still a ways off (although a freeze is likely soon - see below).

Looking back at the satellite image above, the upper system near Las Vegas will be progressing east and north during the next 24-48 hours.  Thunderstorms are going to be possible as this system moves out into the plains.  But the timing will prevent anything widespread until the system gets farther east.  The main risk of severe weather will be across the eastern half of Oklahoma and Texas.  

Here is the expected precipitation for the remainder of the week and into the first of next week....

Looking ahead...

The winds aloft are increasing with a lot of "energy" starting to build up across the Pacific.  As systems move off the Pacific into the U.S., there will be the opportunity for them to intensify into major storms during the next 1 to 3 weeks.  HOWEVER, not all signs are lining up, just yet.  One piece of this puzzle I look for is the blocking across the North Atlantic.  With blocking in this region, storms tend to slow up and amplify meridionally across the U.S.  One index I look at is the North Atlantic Oscillation index (NAO).  Currently it is positive (no blocking) and is expected to persist that way for a while with tends to allow storms to progress rapidly across the country.  But, it can change phases very quickly so close monitoring is essential.
Here is a plot of the phase of the NAO (historical and projection)...
Notice that by next week there is some suggestion that the index will go negative.  I'll be watching that closely as some of the aforementioned systems coming off the Pacific could amplify much more strongly than what is currently expected.

As far as a widespread freeze....

Once this current system moves out into the plains, there should be a "cool" shot of air behind it.  This time of year there does not have to be a really cold airmass to allow for freezing temperatures.  I suspect that temperatures will get to freezing Friday through Sunday, at least as far south as the Oklahoma/Kansas border.  Just how much below freezing will depend on sky conditions and surface winds.  For many areas of the plains, the first "vegetative killing freeze" has not occurred yet, but it is several weeks later than the climatalogical average. 

Again, any system that exists later next week will have to be watched for amplification.