Memorial Weekend Weather Blog

A complicated weekend forecast hinges on the movement of a large mid-level low.

UPDATE: Thu 22 May 2014 / 9:45 p.m.

The latest HPC outlook is calling for even heavier rain to our west over the next 5 days ...if this comes to pass it would be great news for runoff into Lake Texoma (discussion continues below map):

I added a chance of showers for Friday as all of the hi-resolution models are showing a weak "ripple" in the flow bringing some precipitation in during the day at 20-30%. I'm worried that my Saturday percentage might be a little low becuase the NAM model shows quite a lot for ain in the morning; however I will leave it at 30% for now as there isn't any compelling change in the overall scenario. Be sure and watch Tom Hale on Friday for his updates.

The bottom line is that if you have outdoor plans please head inside if a storm approaches until it has passed. Wishing for you a safe and enjoyable weekend - Steve

======================================

 

UPDATE: Thu 22 May 2014 / 10:30 a.m.

The latest HPC precipitation outlook for the next week shows very heavy rainfall upstream from Lake Texoma....if this comes to pass the lake could rise several feet by the end of the month.  The overall pattern is one that favors heavy rainfall to our west Sat-Mon.

Rooting for this...with no flooding for those folks of course.

 

============================================

UPDATE: Wed 21 May 2014 / 9:45 p.m.

Saturday's rain chance now stands at 30% with no significant change to the overall forecast. There will be some "holes" in the rain pattern over the weekend with eastern areas having a lower chance of rain Saturday while everyone will have higher rain chances by Monday. This is the latest NAM model output for mid-afternoon Saturday:

The circled area shows the 9-hour total rain predicted by this model (from sunrise to 4 p.m. Saturday). This is a bit more than forecast in past couple of model runs so the trend seems to be for precipitation sometime Saturday and a 30% is definitely warranted. See the complete discussion  below.

I will post a final update Thursday evening.

====================================

 

 

UPDATE: Tue 20 May 2014 / 10:15 p.m.

The high-resolution NAM model shows a vortmax ("upper level disturbance") moving out ahead of the main upper low on Saturday; often the higher-resolution model picks up on these before the lower-res GFS/ECMWF, so I'm going to include a 20% chance of storms for Saturday as well. Please check in for a fresh update Wednesday evening.

====================================

UPDATE: Tue 20 May 2014 / 5:15 p.m.

The three long-range forecasts that I primarily use (GFS, ECMWF and FNMOC) continue in very good agreement for the rain threat Sunday...and even more so for Monday.

My confidence is moderate that this will come to pass; but it's too early to promise that there wouldn't be at least a small threat of rain Saturday as well.

My 7-Day Forecast reflects the thinking shared in this blog (below) with a 30% chance of rain or storms Sunday and a 50% prospect of thunderstorms and heavy rain Monday.

Look for a fresh update Wednesday evening. Continue reading for a detailed discussion.

==============================================================

 

Memorial Day is a time to honor those who gave their all to defend our freedom, and the Holiday weekend is also typically a time when many head outdoors. 

Your May 23-26 weather will probably come down to a split decision. 

Here’s what we have: a large mid-level low is expected to trudge eastward toward the southern Plains this week:

                                                                 Map forecast for Tuesday noon.

The slow movement will be due to a large upper high centered over Texas blocking its path. The low will also be detached from the main jet stream which contributes to the pokey forward progress.   

Further complicating this scenario, large lows like this one often send out smaller “waves” ahead of the main system. These waves often cause thunderstorms to form, and can be almost impossible to forecast more than a day or two out. 

The high shifts eastward; with uncertainty on when the low begins to affect Texoma skies.

 

The bottom line is rain and thunderstorm chances increase as the low gets closer, most likely Sunday and Memorial Day. I’m basing my outlook on the sinking air around the upper high preventing the smaller waves from generating much rain. 

This leaves the low itself to provide the lift for a period of rain and storms for the second half of the Holiday weekend. 

Take Care,

Steve LaNore

Chief Meteorologist

News 12 / Weather Authority

 

 

Read More Blogs
Comments are posted from viewers like you and do not always reflect the views of this station.
powered by Disqus
Sherman 4201 Texoma Pkwy (903) 892 -8123 Ardmore 2624 S. Commerce (580) 223-0946
Copyright © 2002-2014 - Designed by Gray Digital Media - Powered by Clickability
Gray Television, Inc.