June 21 Severe Weather Potential

The above outlook is based on the latest NAM/SREF/GFS.

Lets take a look at the severe weather parameters that will be in place across the zone.

CAPE will be 500-3500 across the region..

Lift Index is 0 to –8 across the region..

SWEAT index is a large area of 400 + across virtually all of the zone until you get to Eastern Ohio and points east . In eastern Ohio and points East into Western PA (shout out to Jen Metz) the SWEAT index there is less then 300.

EHI is relatively low across the region.. Only isolated pockets approach 1

Lapse rates are about 6.0-7.5 across the region..

With the SWEAT being high across most of the region we can not rule out a few tornado’s , however with the EHI being low they should be more isolated. We will monitor this for any future changes in the EHI.

Weather Synopsis

Currently low pressure is located over Eastern Nebraska. A stationary front extends east from that low to NE ohio at which point it then curves south southeast to a low pressure off the Mid Atlantic coast.

This low pressure should lift into Southern Minnesota by tomorrow evening @ 8 PM or 00z. There is also a cold front extending southward from the low over E Nebraska. and by 8 PM it should be just about thru Iowa and then still trailing back to the southwest approach eastern TX.

It is these frontal systems along with the area of low pressure moving NE that will be moving thru the severe weather parameters in place across the zone.

Now the one thing that could come into play and is what we are currently thinking is that the worst of the severe weather would be closest to the area of low pressure. As you can see by the cloud cover above these low hanging clouds can keep the area from being able to obtain the most out of the day time heating. So its quite likely that the further you are away from the area of low pressure the more likely that it would be just rain with garden variety type thunderstorms. This would most likely be the case from Eastern Ohio and points to the east in the zone above.

We will continue to watch and monitor things to see if we have to make any type of adjustments to this thinking!