Thursday, December 22, 2016

Quick update - 12/22/16

The brutal Arctic air finally retreated this week.  The coldest reading I saw in Kansas during the cold spell was -27 (yes that is 27 degrees below zero) and that was NOT a wind chill reading.  Many locations observed 18 to 22 below zero.  But now, all that brutal cold air has sloshed back into Eurasia and Siberia, much like it was in November!  I'm betting it will return again this winter!

Here were the current temperatures:


In the posts I've done over the past 2 to 3 weeks I discussed two systems for the current period.  The first I thought might move out into the plains around the 22nd, or that would be today.  Indeed there is a system poised to head this way.  It will be weakening as it does move out late tonight and Friday, but it should be strong enough (despite really dry surface air and unfavorable surface conditions) to produce a little rain or light wintry mix later today into early Friday.  It shouldn't be a big deal.

You can see this system on the satellite image:

click for a larger version

In the past 2 to 3 weeks I had also "hinted" at a storm around Christmas.  Well, it does appear that there will be a storm!  But, with the retreat of the Arctic air, any white Christmas snow will end up in the Dakotas!  Such is life in the plains.

In the satellite image, the "developing" system (not yet a storm) is denoted by the blue "M"...

click for a larger version

This developing system (M) should become a vigorous storm as it moves into the western U.S. but it appears that it will move too far north to bring any wintry precipitation to the high plains of Kansas.  BUT, it will likely bring a threat of thunderstorms, at least to eastern Kansas, much of Oklahoma and central and north Texas on Christmas Day!   In the post I did on October 28, I said "I would think the threat of tornadoes across the deep south and perhaps up the Lower Mississippi Valley would surely be higher than normal.  Maybe into Oklahoma and eastern KS?".  

Well, we'll see what happens!

Hopefully the storm will be strong enough to bring at least a brief period of rain or showers to part of the high plains.  I just don't know how far west at this point since the storm has not even developed yet.

Here is the Storm Prediction Centers outlook for severe storms for Christmas Day:

Since I'm headed for surgery, I may not be able to update this blog for a while.

Merry Christmas everyone!

Thursday, December 15, 2016

The Cold and potential for any moisture - update 12/15/2016

I'm sure most of you have NOT enjoyed the cold the plains have been experiencing this past 10 days.  Unfortunately, the coldest air has not occurred yet but is on schedule and will be here very soon.

In the past few posts I had mentioned a "gut" feeling of a storm or precipitation event between the 18th and 22nd.   There is going to be a minor event Saturday (17th) so that would be just a little ahead of schedule, and not that significant as far as snowfall goes.  But what is going to be very impactful is the magnitude of the cold along with wind!

Looking at the satellite image from this afternoon, there were several important features:

Click for a larger map

Normally the position of X1 on the map would be ideal to bring a significant storm to the plains.  But this time the flow is rather complicated.  The X2 and X1 will merge into one (maybe), but even if they don't, both will be weakening significantly as they move east and northeast into what I call the "background ridge position".  In other words, the overall pattern is not aligned correctly to allow these systems to retain their amplitude or even intensify.  In addition, the F on the map is a developing system.

BTW, did you ever wonder what  systems denoted on satellite look like on a regular upper level weather map?  The map below shows the level of 500 millibars, or roughly around 18,000 to 22,000 feet.  The solid lines represent a height of the pressure level and in general the wind flow at that level follow these black lines from left to right.  The colors represent the magnitude (speeds) of the wind.

All three systems approaching the central part of the U.S. will interact with a strong gradient of temperatures from the snow packed tundra of the northern plains to relatively warm air across south Texas.  First, the wind machine will crank up across much of Oklahoma and Texas, along with warm temperatures on Friday.  As the systems come out, the surface will be overtaken by Arctic air which will allow temperatures to plunge to values not seen in several years.  Jetstream dynamics will allow for a band of snow to develop in the Arctic air and where ever the energy can consolidate, there may be be a narrow band of relatively moderate snow for several hours.  The snow will be fluffy and will be blown around by the north winds and won't contain much moisture (dry snow).  Temperatures will dramatically fall and even as much as 60 degrees in less than a 12 hour period!  Lows (actual temps - not just wind chill readings) by Sunday morning should be well below zero across the high plains!

Here were the current temperatures across Canada and the northern U.S. at Noon on Thursday. 

The good news is this brutal cold air will move out rather quickly by the first of the week (19th).  But recirculating the cold will result in coldness, just not quite as cold if that makes sense.

You might also be interested in the X3 on the satellite and upper air map.  It was north of Hawaii but instead of moving east and becoming potentially another storm, it appears (according to computer forecast models) as if it will move south and west!  Hmmm.  I need to watch that.

The L (upper level low) west of the Aleutian Island chain will help produce another system that looks like it will drop straight south all the way to the Gulf of California or the Baja.  Now if this happens, eventually it will move east and north and "could" bring some precipitation by the 22nd, give or take a day.  I'll watch that one.

Finally, with the configuration of the upper flow across the north Pacific (including the upper level low west of the Aleutians), that presents an opportunity for perhaps another system around Christmas.  If you remember in that last post, I had a "hunch" of a white Christmas across parts of Nebraska, Kansas (and maybe the panhandles).  But it is WAY TOO early to predict that with any amount of certainty.  What is likely though, is that there will be a significant warm up before Christmas!  More on that as we get closer.

I'll try and update by the 20th.

Saturday, December 10, 2016

Feed bales will be flying - Update 12/10/2016

This is just a quick update on the cold and "potential" for a storm.  On the post I did on the 5th (read it by clicking here), I discussed a system that was dropping southeast out of the far NW and would bring some snow.  After the system went by, the largest amount I saw in the plains was about 4 inches in far north central Kansas.  Light fluffy snow with hardly any moisture content did fall farther south but did nothing to cause problems or unfortunately to benefit soil moisture.  I also discussed the arrival of the cold and the up-and-down that was to be expected for the high plains.  Temperatures have "warmed" up to seasonal values for this current weekend and that will extend into Monday.  But, then the bottom falls out again, and this time it could potentially be even colder than the first surge (I discussed this too and was to be expected).  For a while now I've discussed the brutal cold and snow that had been across the hemisphere (Eurasia and Siberia) and was expected to "slosh" back to this side.  Look at temperatures early this afternoon across Canada!

click for larger map

This is the coldest air so far this season for that part of our hemisphere.   That source region won't change anytime soon.

Looking at the satellite image (click for larger version)...

The red X1 and X2 will move east during the next several days and will unleash more of that cold air across Canada by Tuesday for the central plains.  Hardest hit will be the northern plains and midwest.  But that won't be the only outbreak of cold.  More will be coming later.

In that previous post on the 5th I also mentioned a time frame for perhaps the next potential storm for the high plains.  Despite nothing showing up on the computer forecast models at the time, I had the period from the 18th through 22nd on my mind.  I'm sticking with that period and there is actually something showing up that "might" help that happen!  On the satellite image above, there are two very important features.  One is an anomalously strong and moist flow of air from the deep tropics up across Hawaii and then curving east, slamming into California.  Guess what?  During a La Nina (which the "experts" with the Climate Prediction Center and others have claimed to be going on), this type of flow should NOT exist!  Ha!  More in the coming weeks on this.

Also on the satellite image is the X3.  This appears to be a new system that is just starting to form.  I have a hunch that this particular system just might become a weather maker for the high plains in a week to 10 days.  I'll keep and eye on that and update later in the week.

In the meantime, nothing or very little moisture is expected across the high plains during the next 7 days.  There will likely be fluffy meaningless snow with the cold surges but no impacts are expected.

Here is the Weather Prediction Center's outlook...

Look at how much moisture is expected along the west coast!  WOW!  For the high plains of Kansas through West Texas and eastern New Mexico, as I mentioned, not much if anything.   But maybe there is some hope by next weekend and for the period leading up to Christmas.

The screaming message...a brief "warmup" followed by the deep freeze once again by Tuesday and this should persist for a week or two or three (except maybe a day or two of a brief moderation). At this point it is appearing that average temperatures for December will end up below normal across much of the area.  I'm thinking there will be a lot of breaking of ice and supplemental feeding for livestock.

Also, a gut feeling is for a "white" Christmas for much of Kansas and Nebraska (and maybe even the Texas/Oklahoma Panhandle region. Ha, we'll see how that one goes, i.e. don't tell anyone. ;-)

Monday, December 5, 2016

Update 12/5/2016 - the cold is on it's way

In the post I did last week on the 30th (read it by clicking here), I showed a system that was along the northern border of Washington state and was expected to dive way south into southwest Texas.  Did that happen?  Look at this mornings satellite image:

click for a larger map
This system did develop as expected.  On the map, the system is denoted by the red "L" near El Paso.  It has brought very heavy rain to much of Texas, parts of Oklahoma and is now soaking the lower Mississippi Valley and eventually the parched southeast U.S.  Good for them!  What I was not expecting was enough lift of the atmosphere across the central U.S. from a passing upper level trough (mostly unrelated to the upper low but the northern branch of the westerlies) to produce much precipitation.  Some areas of the central U.S. did receive some beneficial rains (and a little bit of wet snow)!

Here is a map of precipitation from over the weekend:

Click for a larger map

Anything from about Amarillo to OKC south is related to the upper low.  The remainder north of that line is a gift from the northern branch of the westerlies!

In the previous post I also talked about an upstream system that could bring snow Tuesday and Wednesday, but also cautioned to seeing predictions.  Computer models are and have been all over the place!

On the satellite image above, there are actually 2 systems.  One was over northern Wyoming and will become a pretty decent storm for the northern Plains and upper Midwest/Great Lakes region.  Nothing for the central U.S. other than providing a cold front that will sweep across the high plains Monday night into Tuesday..

The other X (2) was approaching Washington state and you can see the expected path it should take.  It will be a compact system and thus will bring a narrow band of precipitation (snow) as it moves out across the central U.S. on Wednesday.  It looks like any significant snow will be confined to northeast Colorado and western Nebraska and perhaps far northwest Kansas.  Lighter snow (less than 2 inches) will fall on a line across mainly the I-70 corridor as far east as Manhattan.  Some of that snow could creep a little farther south, but it shouldn't be much (a dusting to 1 inch).

Through the next 7 days, here is the outlook from the Weather Prediction Center:

After this second system moves through, a brief period of even colder air should spill south across most of the area Wednesday and Thursday.  That would be just a couple of days faster than I originally expected (in the previous post).  But as I also previously expected, it will likely be just a brief visit as there will be a warm up (to seasonal values) Friday and Saturday.  But, that might just be the start. There is some pretty cold air to be tapped into and it looks like this cold air will slosh back and forth for at least 10 days to 2 weeks (maybe longer) centered on the central and northern plains.  Thus, areas of the high plains will see wild swings from really cold to brief warmups.  The upper midwest and northern plains may be set for the deep freeze for an extended period well into December.  The first slosh back into the really cold might be as early as the end of the weekend.  Every time that happens, there might be a brief period of fluffy light snow.

Here is the morning map of temperatures:
December is typically (based on climatology) the driest month of the year.  At this point it sure doesn't look like it will be any different.  As the repeating pattern length starts to reveal itself, I might be able to pin down the next chance for a "significant" chance of a storm.    I'd like to say between the 18th and 22nd, but the confidence in that period is near zero but it's stuck in my mind.  I'll try and update towards the end of the week or weekend so check back.  In the meantime, prepare for periods of really cold air and then it's back to near seasonable temperatures for a few days before going back into the deep freeze.Break out the feed bales!

Wednesday, November 30, 2016

Updated 11/30/2016 This pattern is ridiculous!

In the previous post I did a week ago on the 23rd (click here to read it), I  discussed AGAIN about the Facebook poster out of Oklahoma.  He is still at it and out of control.  Look, he posts NOTHING but computer output from the Global Forecast System computer model.  ALL computer models will vary from run-to-run (at least every six hours) and sometimes dramatically!  This fall, so far, these computer models have failed miserably in predicting even the location of the jetstream (location and intensity), let alone details of precipitation (including snowfall) and temperatures, which cannot be predicted with any degree of accuracy beyond a couple of days.

This has been a really tough pattern to nail down.  There has been so much cold and snow across Eurasia and Sibera.  I mentioned in the previous post that eventually that cold would slosh back to our side of the hemisphere.  That is starting to happen, which I will discuss below.

In the previous post I said "The one for the end of the weekend is ALSO on schedule but it looks like mostly wind as it will follow suite and track too far north.  There are other possibilities by Tuesday and Wednesday. There has to be some development in the flow aloft to bring any threat and I will discuss the possible development below."

The storm for the end of the Thanksgiving weekend was right on schedule and for the high plains, unfortunately, it did bring mostly wind (and a lot of it)!  There was some light rain but it did virtually no good as it warmed up and got very windy by the end of the day Sunday.  This is NOT a good trend and something I'm watching very carefully!  

The other possibility I discussed (Tue/Wed) also was on schedule but brought very little again to the plains. There was very heavy snow across the Dakota's and sadly killer tornadoes across the southern U.S..

It is very discouraging to have so many systems this past 2 weeks come through with very little in the way of precipitation and so much wind.  Plus, no really cold air, at least yet.

So now what?

I ended the November 23 post with "Active and sometimes stormy weather should be expected for the first 1 to 2 weeks of December. " and that still looks on track.  The pattern is starting to show signs of repeating from where it developed.  That is to say there should be some amplified systems during this next couple of weeks.


Looking at the latest satellite image...

click for a larger map

The red X over eastern South Dakota is too far north to give the high plains any precipitation and it was moving away.  More importantly was the big blue H over central Canada.  It has blocked any storm from moving through but actually is in a position to allow cold air to spill into the states.  The only problem is there is very little cold air, yet!

The red X near northern Washington is our next weather maker.  But there is a huge problem!  Because of the blocking across Canada and ridging across the northern Pacific, it looks like this system will drop due south and perhaps all the way into southwest Texas and then turn due east!  That is too far west and south for the plains to benefit!  This would bring heavy rains to central and eastern Texas and the lower Mississippi Valley by the end of the weekend leaving much of the high plains high-and-dry!  Confidence in this is reasonably high in that scenario but there is still a very small outside chance the system wouldn't drop that far south.

It also depends on any upstream storm that could "dig" into the west kicking the first system out sooner.  There was at least one system that could do it (not shown on the map).  Also that particular storm has  a very small chance of developing enough to bring some precipitation to the plains about Tuesday or Wednesday.  Don't count on it, regardless of what you might see from some outlets.  

The upshot is I have extremely low confidence and unfortunately at this point have a very pessimistic outlook for any of these systems benefiting the high plains.

The Weather Prediction Center from the National Weather Service offers the following possibility for moisture during the next 7 days.

At this point, the only advice I can give is to not expect much across the high plains during the next week to 10 days.  But there is a small chance; just hope and pray.  The cold air that is sloshing over into our side of the hemisphere is already impacting Alaska and northwest Canada with some brutally temperatures.  Eventually (maybe by December 10-12) this will cut lose into the central part of the U.S., at least for a brief visit.

I hope to be able to update this blog by Sunday, so stay tuned.

Wednesday, November 23, 2016

Update 11/23/2016

Viral posts from sources you can't trust. It pertains to weather AND news!  I'm sure some of you have been reading posts from the person on Facebook down in Oklahoma.  He claims to be a degreed Meteorologist so a lot of folks take to heart what he has to say.  Don't get me started...UGH! 

Anyway, as I've stated in the past, computer forecast models sometimes fail at 12 hours, let alone 300+ hours in time.  Details of elements such as snowfall or accumulated precipitation on a spatial scale and time scale (even within 12 hours) are just numbers.  There is NO predictability of such.  If you see it, ignore it.  So what this guy on Facebook shows you is nothing more than computer output that will, and often does, change dramatically every time the forecast model is run (every six hours).  No doubt that once in a while the forecast model will be really good and close with those details!  But that is just pure statistical luck.

In the post I did on the 17th (you can read it by clicking here) I discussed several potential storms.  The first system was going to bring mostly wind to the high plains.  Oh boy.  Did anyone see the downburst video I posted on the NWS Facebook page that was taken in Sublette?  That was a dramatic example of a downburst from an elevated thundershower (there was some lightning and thunder but hardly any rain).   Click on  downburst to see it.

The second system I discussed was expected Monday or Tuesday.  It was right on time and brought rain to northern and eastern Kansas and some rain and snow to eastern Colorado.  But for the majority of the high plains of Kansas and down into Texas....nothing (went too far north).

The next system I discussed was due around Thanksgiving or the following day.  It also is on schedule (shown on the satellite image below).  But it is too weak and too far north to bring anything to the high plains.  It will bring a little snow to parts of the Dakotas.

Then I wrapped up that last post with the following: "Yet another system will be possible by the end of Thanksgiving weekend and perhaps the biggest threat another around the 1st or 2nd of December! Details are highly uncertain at this time.  The point is the pattern is finally getting active and should stay that way into early December.  Hopefully at least one of these systems will benefit the plains with decent moisture.  Temperatures will be more seasonal and at times quite a bit below normal."

The one for the end of the weekend is ALSO on schedule but it looks like mostly wind as it will follow suite and track too far north.  There are other possibilities by Tuesday and Wednesday. There has to be some development in the flow aloft to bring any threat and I will discuss the possible development below.

First - the west Pac.

There was (and has been) a response from convection across the western Pacific Ocean area.   There still is a transfer of latent heat energy into the mid-latitudes (the green arrows pointing up and to the left).  Also, some of the very cold air across Siberia has been moving east across the northern Pacific. There are other things going on but this should all point to some downstream amplification.  Also, the red X is not a typhoon but is at least an organized system.  Usually something in this position as it moves west and north causes amplification too!

Closer to the states:

(click for a larger image if you would like)
There was a vigorous storm across the Gulf of Alaska with upstream ridging of the upper wind flow.  This storm should pound the Pacific Northwest.  There was also significant ridging (moist upper flow moving north) west of Hawaii.  This I find rather interesting.  I'm not totally sure how that might come into play but I think it will.  I'm going to watch that for a few days.

Over the conus:

(click for larger version)
The red X over southeast Minnesota is what brought some precipitation to the central part of the U.S. late Monday and yesterday.  It had weakened considerably.  The other red X over central California is the Thanksgiving system that will mainly impact the Dakotas.  Part of the issue with that system is the HUGE blocking high (the blue H) over southern Canada.

In that post I did on the 17th, I discussed the North Atlantic Oscillation (NAO) as being one of the keys that might help the upper flow buckle and become stormy across at least the central U.S..  I was looking for the index to go negative (and it has been forecast to do so with a degree of error).  Here is the latest:

It has reached a neutral index and is still expected to go slightly negative.  That "might" be enough to contribute to some blocking and amplifying of the pattern but combining with the current state of the flow across the Pacific "will" make it happen.   That Arctic Oscillation (AO) index continues to be negative and is expected to continue.  This is in spite of an anomalously warm high latitude Arctic region: