Friday, May 29, 2015

Update 05/29/15

Due to priorities at work, I have been unable to post here.  But with a few minutes available, this post will be short.

In previous posts I discussed the wetness was upon us and discussed possible historic flooding.  I guess I don't have to tell you - it happened.

The drought, which had been declared as Extreme in some areas, is now gone for much of the area.  There is still locations with an official moderate drought. (click for a larger version)



Now what?

It does finally appear a change in the pattern is developing that will start to dry things out.  During the next week to 10 days there will still be scattered areas of thunderstorms.  But, no where like it has been.

From the Weather Prediction Center - the outlook through early Friday, June 5th.


I will do a more in-depth review/outlook next week.  It's been just a crazy week or so.  The short of it is that there will be drying and warming temperatures. But, the drying could be returning in a couple of weeks.  I need to look closer at the data and trends.  More later....


Monday, May 18, 2015

Wettnes - Updated 5/18/15


In the post I did last Friday (click here), there was a discussion about the possible severe weather for Saturday the 9th.   I mentioned that if there was a lot of convection the previous night, then the chance for severe weather would be diminished.  Indeed that was the case, again!  The previous Saturday (2nd) saw the same thing happen.   There were tornadoes across northwest Texas and western Oklahoma (with isolated ones in eastern Kansas).

With the rains that fell with the weekend storm, the accumulated precipitation for the month of May through the 17th is very impressive!  In fact, amounts are as high as 600 percent of normal across parts of the plains (from the Dakotas to West Texas)!  Amazingly there are still a few locations that have generally missed out.  (as always click for a larger version)



This week there will be several more upper level storms impacting the high plains.  The first will be late tonight into Tuesday night and it will bring widespread rain, especially to the western high plains.  There will be a minimal chance for severe weather closer to the warm sector across the southern Texas panhandle and west Texas.  Rainfall amounts with this system will be generous!

The latest satellite image shows the system across the west.


Also, the low and dip in the jet stream (the green arrow) over Minnesota has already brought heavy snow and freezing temperatures.  The bad news, even colder air is expected for tonight.  Freeze warnings are posted for the Dakotas and even a frost warning for parts of Nebraska.  I just saw where Minnesota has 95% of the corn planted with North Dakota not too far behind.  Has any of it germinated?  If so, I guess there will be replanting.


Another strong system will be approaching the plains during the weekend and just like these past two Saturdays, there will once again be the threat of severe weather.  But, just like the past two, the chance for severe will be mitigated if overnight storms Friday night stabilizes the atmosphere.  Regardless, addition rains (and some excessive) will occur.  In fact, combining all the expected rainfall from tonight into early next Monday (the 25th), the potential for severe flooding is increasing!  Actually, eventually some of the accumulated rainfall could produce record flooding at some locations so we will need to start thinking about that.  Look at the Weather Prediction Centers outlook for potential rainfall through next Monday.


One of the reasons for the anomalously cold and anomalously wet weather is the contribution from a Rossby (or planetary) wave train of downstream propagation.  The source has been several western Pacific Typhoon's.  A very similar pattern was in place back in December.  In fact I discussed the very same situation in the blog I did on December 1.  Go back to that post by clicking here.

The current wave train...



I'll try and post later this week and I will discuss an issue that may appear before long.  That issue?  Too much rain!  Too much rain?  There is a possibility that a feedback will start to occur and overall wetness and cooler temperatures will persist well into June.  Will there be weather conditions that will allow the winter wheat to mature?  If so, what about getting the grain out of the field if mud persists?  What about getting all of the corn, sorghum and cotton planted if it stays wet? These may be legit issues.  Stay tuned...

Friday, May 15, 2015

Quick update - 05/15/15

In the post I did on Wednesday (click here), I discussed the system that would be impacting the plains this weekend.  There will likely be some severe weather today, but the bigger impacts may be on Saturday.  The Storm Prediction Center currently has the following outlook in place (subject to change)...



The issue tomorrow may be what happens to the atmosphere with thunderstorms during the overnight hours tonight (Friday night).  The atmosphere may have to spend some time recovering, much like what happened last Saturday.  If the amount of activity is marginal tonight, the risk for the day on Saturday increases. Stay informed by going to weather.gov and clicking on the part of the country you are located.

Additional rains will occur with this system but will miss some locations.  That may actually be good for some areas as excessive rainfall has occurred during the past 30 days.  Go back in the previous post and see the map I provided.

With the recent rains, the drought has improved immensely, especially across Oklahoma and Texas!


The change from the previous week was incredible!


Now we're headed into a colder period (all relative to May) so it appears that during the next several weeks the AVERAGE overall temperature trend will be below normal.  I think there may even be a decent chance of freezing temperatures all the way down into parts of Nebraska later next week!

With the change to "colder", the flow aloft will be favorable for additional precipitation next Tuesday through Thursday.  The Weather Prediction Center offers the following possibility through next Friday:


However, I think they may be shorting the front range of Colorado for next week. 

Wednesday, May 13, 2015

More rain and storms - Updated 5/13/15

The upper flow has definitely got more favorable for severe weather and rain this month. After a break from the weather over the weekend, the latest system was lifting northeast across the central and southern plains this Wednesday afternoon.  Widespread showers, with a few isolated thundershowers, were progressing across the area.  No severe weather was anticipated with the system.

The precipitation forecast for this first system provided by the Weather Prediction Center (likely too much in general).  Click for a larger map.

This rain is on top of the excessive rainfall that has occurred over the past 30 days.  The following map is a total for the past 30 days ending this morning (before the current round).  Click for a larger version.


A closeup of Oklahoma....


Before I discuss the next system... The past weekend storm not only brought severe weather with tornadoes, but it also brought heavy snows and freezing temperatures.  The snow cover map for Monday showed...


Low temperatures behind the storm fell to freezing or a little colder across much of the high plains north of Dodge City.  There no doubt was some wheat damage on fields that were flowering. I haven't heard about the corn.


Attention is then drawn to the west where another strong upper system was poised to move out of the western U.S. this weekend.  Another risk of severe weather is likely.  The question is timing and the exact location which is unknown this far out, due to mesoscale processes that are not predictable.

The satellite image shows the current weather maker and the next gaining strength across the west...


The low across the Pacific Northwest will dive southeast.  The best threat of severe weather will be Saturday across the plains.  Again, there are just too many uncertainties to pinpoint a location.  Also, the next several storms will keep adding the precipitation.

The Weather Prediction Center offers the following possibility of precipitation through next Wednesday...

As I stated in the post I did on the 11th (click here for that post), I discussed the flooding that had already occurred and the expected additional flooding that will materialize as addition rains occur.  Even on the middle stretches of the Arkansas River in Colorado has seen flooding and more is likely.

Looking further into the future, it appears that this wetter pattern will likely persist well into June and perhaps longer.  More on that later.

Monday, May 11, 2015

Update 5/11/15

In the post I did on the 5th (click here) I discussed several items that have panned out so far.  Go back and review that post.

I discussed the active severe weather that was expected.  During the past 7 days (5/4 - 5/10) there have been numerous tornadoes, a lot of hail, a lot of wind and in some spots copious amounts of rainfall.  There was even very heavy snow across the northern high plains.  Rapid City received nearly 14 inches of snow over the weekend.  There was even blizzard conditions at some locations in the Nebraska Panhandle.

As far as severe weather reports during the period, there have been 153 tornado reports and 333 reports of large hail.  A map of the plot follows (click for a larger version)....


Precipitation has also been excessive but still there are a few spots that have been missing out. The following is the estimated precipitation during the past 7 days ending this morning (5/11)...Click for a larger version...


This week and into the weekend the atmosphere will "reload" with additional episodes of severe weather expected, especially later in the week and into the weekend.  As heavy rain events continue to unfold, I'm afraid that there will end up being extremely serious flooding across north Texas and much of Oklahoma.  Even across parts of Kansas and Colorado there may eventually be flooding issues (there already has been some across the front range of Colorado).  

Also, at this point, the overall wet pattern may persist into June.  As I stated in the previous post on the 5th, the number of 100 degree days (or excessive blow torch days) will be much less this summer.



Tuesday, May 5, 2015

Update - May 5, 2015

In the post I did on Saturday the 2nd, I mentioned that the pattern would be getting active.  Yesterday (Monday) there were numerous thunderstorms stretching from southeast New Mexico and southwest Texas all the way to Nebraska and Iowa.  The was spotty hail reports and a couple of brief tornadoes.  The biggest event was local flooding.  Some areas received copious amounts of rain and unfortunately soil eroding flooding.  The following map shows the precipitation for the high plains and other parts of the adjacent plains.  Click for a large version...


The upper level storm partly responsible for the active weather was still over northwest New Mexico this Tuesday afternoon.  Additional rounds of weather will continue into Wednesday from this system.


Unfortunately, the threat of severe weather from this low will be increasing, especially on Wednesday.


Back to the satellite image, there is another dip in the jet stream developing across the far northwest part of the country. It looks like this may dig southeast and bring another threat of severe weather and lots of precipitation later in the week and into the weekend.

The Weather Prediction Center offers the following possibility (forecast) for the next 7 days.

Overall the pattern is pointing to above normal rainfall for this month and even for June.  With the rainfall that has been occurring across west Texas, and with additional rain possible, the chance for seeing day after day of 100+ temperatures for this summer is decreasing.

I'll discuss the outlook later this week - and after the latest drought map is released (which we should see a vastly improved map).

Saturday, May 2, 2015

Update - May 2, 2015

In the last post I did on the April 28th, I showed a map of the widespread heavy rainfall event that was centered on west central Oklahoma.  This made a huge dent on the on-going drought. April ended up being very wet across the hardest hit areas of the drought and there has been much improvement.  At some locations the improvement was dramatic!


Due to other obligations, I cannot write up a detailed post about next weeks weather (I will do my best on Monday).  But, it does appear that it will get active across the plains, including west Texas and the panhandles!  Some areas will get heavy rains again!  But, also the threat of severe weather will be increasing so crop ending hail will be occurring in some of the bigger storms.  The Weather Prediction Center offers one possibility on moisture - don't take the amounts and locations literally.  In general though, many areas of the plains will see 2 to 3 inches of rain next week (and some locations over 5 inches) .  Unfortunately, there will still be a few spots that don't benefit much.  The good news is that additional active weather will occur the following week.