Warmth & Severe Chances Increase..

We have been talking about the pattern that has been in place and seems to be setting up for at least the forseeable future of a day or two of warmth followed by strong cold fronts bringing temperatures back to seasonal or slightly below normal levels.

We see this scenario playing out on the guidance once again with warm air coming due to ridging pushing east and then cold fronts coming thru with the chance at some severe weather. While timing issues are always in play at this range out we have come up with two time periods and the parts of the region that may have to watch for either severe weather or in general thunderstorms. These are based on severe weather parameters that are in place..

First a look at the warmth that is coming:

The 12 Z ECM is bringing temperatures in the 75-80 degree range at 120 hrs out across a large part of the region.

The 12 Z GFS starts to bring temperatures into the 60-70 degree range on southwesterly flow at 102 hrs out and then at 126 hrs out it is in agreement with the European Computer Model..

The first round of thunderstorms could occur on Sunday as the warm front moves thru the region and the clash of the cooler seasonal air mass in place with warmer air arriving. The 12 Z GFS is showing some decent parameters for severe weather at that time..

 

12 Z GFS is showing CAPE across parts of the region of 1000-2000 and some pockets of 2000-3000.

Lift index of 0 to –4 and pockets of –4 + .

Mid Level Lapse rates are decent across the region with 6.5-7.0. The one area that i would like to see stronger between now and then & could act as a limiting factor is the lack of any real shear..

So based on the above factors we have come out with two very early preliminary maps for severe weather chances. The first as mentioned being sunday..

And the second one being monday into tuesday..

These maps are preliminary and highly subject to changes as timing of the cold front may change between now and then.

Never the less get ready for another roller coaster ride of temperatures with them rebounding into warmth and then falling back down there after.

Stay Tuned for more information..