Amazingly, despite what will likely be the warmest spring on record in the Delaware Valley, we have yet to hit 90 degrees.

The potential for the season's first 90 degree day looms large over the next couple of days, and today's Memorial Day holiday might be our best shot in this upcoming summery stretch. Despite a chance in the forecast for some pop-up thunderstorms, most of us should dodge any thunderstorm development in the afternoon hours.  In place of rain and thunder will be heat and humidity in what may be our hottest day of the year so far. 

The hot party won't last for too long.  A cool front in the Great Lakes states will slowly work east and cross the region on Tuesday night and Wednesday.  Cooler weather will gradually ooze in to replace the heat and humidity, and that clash of air masses will lead to more thunderstorm development on Tuesday evening.  Those storms could be a bit more widespread (or at least on a line) as they sweep through the region. 

Tuesday won't be the last of the precipitation chances, either.  Another storm system will organize in the Great Plains and march east and northeast for Friday night and early Saturday.  This will bring another shot of rain and thunder to the region.  However, Tuesday's front will cool us down from near 90 to the 70s and 80s, which is much more typical for late May and the start of June.

Lastly, the system now known as Beryl may throw some showers into the Delmarva, but it will not be a direct threat to our weather.  Computer guidance as of Sunday afternoon and evening will bring the system back out over the Atlantic in a couple of days and then send its remaining moisture northeast and safely out to sea.