We're Having a Heatwave

We're having a heatwave, a tropical heatwave, the temperature's risin', it isn't surprisin'.....I can just hear Elle Fitzgerald sing away describing the weather early next week.  A heatwave is defined as 3 consecutive days of 90F+ weather and I believe that will be attained by next Tuesday assuming we hit 90F on Sunday.  I'm concerned about some lingering showers and thundershowers for Sunday, but the bulk of the rain will fall now through Saturday evening.  Both the Euro and the GFS suggest the 850 mb temps will support surface temps at or above 90F as an upper air high pressure builds and strengthens over the Mid-Atlantic.  Below is the map for next Tuesday morning showing the 850 temps and the high pressure over our region.  In fact, with westerly winds downsloping off the mountains, KMDT should hit 90F Sunday through Wednesday.  Dewpoints will also be quite oppressive during this stint of hot weather.

By next Thursday, this surge of heat and humidity will be replaced by the low that is seen above over the northern plains, moving to the ENE and dropping a cold front down across PA late Wednesday and early Thursday.  If fact, if this moves faster than projected, then 90F will not be achieved Wednesday due to the clouds from advancing storms that will accompany the frontal passage.  The map below shows the 850 mb trough carrying cooler air towards PA thanks to the counterclockwise circulation around the low over Quebec.

By next weekend, it appears as if PA will be under a NW flow ushering in "normal" temps with low humidity, weather that would be described as ideal by many for this time of year.  However, once the heat comes up "over the top", another surge of "dry heat" may be moving in on NW flow which is not too unusual for the summer season.

As many of you are aware, there was yet another bout of severe wx here in PA Thursday evening.  In fact, 3 tornado WARNINGS were issued for our area Thursday afternoon and evening!  This is just some of the energy that ravaged the mid-west earlier this week as this potent storm grinds its way to the northeast and wreaks its weather havoc over the eastern 2/3 of the US!  The graphic below shows the severe storms report in the last 24 hours.  We will have some feisty storms yet again Friday afternoon.  This low level heat and humidity coupled with the cold air aloft and at the surface to our WNW (it was 48F in Chicago at 6 pm this afternoon) will once again do its dirty work and create heavy weather in our immediate area.  Unfortunately, I do believe that there will be numerous "lightning delays" at the state track and field meet both Friday and Saturday.

As for us this evening, Etters dodged the proverbial bullet, unlike the apple below.  We had some wind, heavy rain, but no hail, minimal lightning, and quite frankly were very lucky.  I hope all of you came through as unscathed as we did here in the metropolis of Etters, PA.

Enjoy your Memorial Day Week's end!

Smitty

AA:  Storms Friday and Saturday....maybe even Sunday, but getting hot and humid for Monday-Tuesday-Wednesday....then normal and "nice" wx for the end of next week!