Increasing Heat & Increasing Severe Potential June 1st!

There is absolutely no doubt when looking at the guidance over the past couple days , including today that we are headed into a time period that will consist of “Hot & humid” weather.

The problem that comes to this type of weather pattern is if you have an air mass that is hot and humid and above normal you run the risk of severe weather. Before we get to the severe weather potential lets look at the heat

As you can see guidance is suggesting that with the warm southerly flow that temperatures are going to be in the 80s to 90s all the way into the Northeast. So folks first and foremost be prepared for some hot weather over the next couple days.

Now, lets look at the 850 mb level maps that show you where the low pressures are located and anticipated to track..

Now lets look at the ECM for the same time period..

Now as you can see both models agree in an area or low pressure over the Dakotas with the GFS just slightly deeper and that area of low pressure moves towards the ENE into Southern Canada North of the Great Lakes.

So you ask what is the big deal? Whenever you have an air mass that warm out ahead of a setup like this…associated with this area of low pressure will be a cold front and watch what happens. First at the 850 mb level..

Notice the drop off from +20 to only + 6. GFS is not that much different from the ECM other then the timing is different.

Notice the drop as well in agreement with the ECM or European computer model. So the upper levels of the atmosphere are going to cool off significantly ..what about the lower levels at the surface?

Notice the highs are only in the 60’s,70’s range. So we are looking at a significant drop in temps at the surface as well.

So the heat builds in, low pressure moves ENE drags a cold front and all that is needed is severe weather parameters in place and the area is looking at a severe weather outbreak. With guidance in agreement on the pattern it seems that the potential for a severe weather outbreak is quite likely on Wednesday.

At the current time we are looking at severe parameters in place as follows: (Yes these will change for those that may wonder)

CAPE 500-5000 depending on your location

Lift index is 0 to –10 depending on your location

SWEAT from 400 –450 in the NE from central and eastern PA into the NE

So with all the above and the ECM also in agreement we feel that with confidence we are able to issue a preliminary map for wed for severe weather.

Now we realize that the specific parameters are likely to change between now and then but the map is more based on the synoptic set up as described above so we do not think we will have to make to many changes to the zone itself but as we get to tuesday we will narrow down the most likely area to receive the greatest severe weather threat so you know what to expect the day prior!

Stay tuned for further updates on this pattern !