Severe Weather Potential May 20th

The following map issued above is the severe weather potential for May 20th. The map is based on the SREF/NAM.

Severe Weather Parameters in Place

CAPE- 500-2500 depending on where you are located

Lift Index o to -6 depending on location

SWEAT index 500 from west central OK south into east central TX

EHI once again is not overly impressive but is greatest in central OK at 1 to 1.5 in combination with the SWEAT index this could end up being the best place for isolated tornado's.

Weather Synopsis..

Early morning friday around 12 Z or 8 AM low pressure will be located over southwestern NB. From this area of low pressure is a warm front extending to the east south east thru Missouri. Also extending to the south and then Southwest of the low is a cold front which should be thru the Panhandle area trailing back to the west across the southern border of New Mexico. This low pressure will slowly move off to the North and be over south central South Dakota by about 00z or 8 PM with the warm front lifting towards the Northeast slowly thru out the afternoon and the cold front progressing slowly towards the east.

 

Meanwhile you can see looking at the water vapor image above a spinning circulation across the four corners region. This is going to start to move towards the plains states today and be located there tomorrow. 

These storms will originate due to various factors. The warm front will be a focusing mechanism. Also they will be occurring due to warm air advection and strong lift out ahead of the advancing trough.

There is a question as to how much effect the MCS system (currently) will have on tomorrows outlook ..however with destabalization taking place in the warm sector out ahead of the advancing trough and cold front ..the atmosphere should be able to recover with the day time heating from any MCS occurring overnight tonight.

Once again the greatest threats with this outlook will be the winds and large hail potential , along with a few isolated tornado's already highlighted in the discussion above. Keep in mind though that there can also be isolated tornado's anywhere along the warm front.

There may be more thunderstorm activity across parts of the mid atlantic into the Northeast but Parameters really are not supportive of highlighting this area . Greatest threat with any cells there would be heavy rain!

Stay tuned for further updates if it should become necessary!

Time currently: 6:52 PM EST