June 22nd Severe Weather Potential

We are now under 24 hrs and the SREF continues to be not too impressed over all with the severe weather potential for tomorrow. The NAM also is over all not that impressed as well and the GFS is not out yet at the time of this writing because we want to get this out before the 22nd actually starts.

Normally we would start off with the severe parameters but this time we are going to do things backwards and take a look at current conditions because the outlook above hinges on what is happening presently and how long it lingers.

First a look at the current infrared satellite! As you can see by the above there is expansive cloud cover from the great lakes heading into the PA region and to the south east of there with some breaks to the southwest. Underneath these clouds is the following:

You can see these clouds are causing for the most part now some rain and garden variety type thunderstorms across the region.

Currently there is a low pressure over Southwest Minnesota and extending from this low pressure to east just to the north of PA is a stationary front to a low pressure over the central NY/PA border. Another low pressure is over N Va.A cold front is also extending south and then southwest from this low cutting the state of Illinois in half and then cuts back into TX pretty close to the Abilene Tx area. The southern part of that cold front near Abilene is causing a Squall line to occur currently.

The low pressure area over Minnesota will slowly advance towards the east before starting to drop to the southeast and should be located over the Iowa/Wisconsin border by 8 PM. This will cause the cold front to move towards the east and the warm front to basically straddle across NE PA with a low pressure developing almost over the NNJ/NYC vicinity.

It will be this cold front and the warm front that would serve as the focal point for showers and thunderstorms to develop.

Now, the wild card is that this low pressure that will be moving east and then dropping east is going to be weakening. Also in addition to this is the current cloud cover and precipitation that is going to be moving thru in the over night period could really put a damper on any severe chances especially east of say Ohio because it the overnight convective rain and garden variety storms will help to stabalize the air and with the cloud cover in place..if it does not burn off quickly we will be left with just rain and garden variety thunderstorms.

So, there are variable factors and equations at play here and this is not a sure fire outlook in the sense of a good part of the region could just end up with garden variety thunderstorms and heavy rains.

Now, closer to the low pressure system over Minnesota we feel will again have the best chances for severe so this would be in the zone from Ohio /indiana region and then right along the actual cold front.

So with that said lets now look at the parameters in place..

CAPE is anywhere from 500-3500 depending on where you live!

Lift Index is anywhere from 0 to – 6 depending on where you live.

SWEAT is generally under 400 everywhere with the exception of Extreme SW TN and NE Arkansas to North Central ARK

EHI is highest above 1 to about 1.5 from Western TN back into the same areas of Arkansas listed above.

So that is the latest and we will continue to watch and monitor and make any adjustments if necessary.

For summary we think the greatest threats are going to be wind and hail and tornado’s will be isolated with the low pressure weakening and with all the current convection potentially putting a damper on the overall threat.