Frontal System Moving Through Pennsylvania; Watch Issued For Portions Of Mid-Atlantic

Could be a stormy late afternoon and evening throughout much of the Garden State.  A cold front being pushed eastward by a strong northwesterly flow is pushing into a warm, humid air mass that has been responsible for temperatures and dew points being on the rise over the past several days in New Jersey.  A Severe Thunderstorm Watch has already been issued for portions of the Mid-Atlantic, and that could stretch eastward into New Jersey.

After a high of just below 80 on Sunday in South Plainfield, the mercury climbed up to 86 at GWC on Memorial Day with humidity levels also on the rise.  Today, the thermometer climbed up to 84 earlier this afternoon before some clouds moved in.  The temperature dropped a couple of degrees to 82 as of about a half an hour ago (2:30 PM EDT).  The sun is trying to make a bit of a comeback in just the past few minutes, and the temperature has gone back up a couple degrees to the day’s high of 84 (3:17 PM EDT).  Then, there is a dew point, which is at 67 degrees in South Plainfield.  The combination of heat and humidity produced a peak heat index of 88 degrees at GWC earlier Tuesday afternoon.

The past 48 hours have seen the warmest weather of the spring here in Central Jersey.  Yesterday’s highs in the mid to upper 80s were the warmest of the month.  The high of 86 on Monday at Greg’s Weather Center was the warmest of the month, and the highest temperature of the season.  The previous high for the season was back in mid-April when the mercury topped out at 83 degrees, which was the first time that had happened since the first week of October 2013.  Despite the summer like feel to the air over the past two days, high temperatures for May 2013 are still down from the previous three years, which had peak highs of over 90 degrees.

The summer like weather is going to come to an end though.  A back door cold front is slowly pushing to the east, and with it, a significant change.  High temperatures on Wednesday in New Jersey are forecast to only get into the mid 60s.  So, we are looking at about a 20 degree drop in temperature in just 24 hours.  In addition, the air will also dry out behind the front with a northwest wind ushering it in.   With all of that said, there is a clash of air masses taking shape in the Mid-Atlantic, and that is already producing strong to severe thunderstorms across a large swath of the region including much of Central Pennsylvania.  Already seeing reports of high winds and large hail along with plenty of lightning.

About an hour ago, the Storm Prediction Center in Norman, Oklahoma issued a Severe Thunderstorm Warning until 9:00 AM EDT.  The area covers an area from South Central New York, through Central Pennsylvania, into Maryland, Washington D.C., Eastern West Virginia, and a good portion of Virginia down to the city of Staunton.  Storms containing 70 mile per hour winds, 1.5 inch diameter hail, and dangerous lightning are possible within the watch area.  These storms could still pack a punch as they move eastward into Eastern Pennsylvania and ultimately our area later this afternoon and this evening.  Events such as the Greater Middlesex Conference Tournament Baseball Championship scheduled for 7:30 PM tonight at TD Bank Park in Bridgewater could be in jeopardy.

If you’re planning to head out later this afternoon and this evening, keep an eye to the sky and be prepared for strong to severe thunderstorms.