1:00 PM | **High heat and humidity today in the Mid-Atlantic region with a tropical connection…refreshing air mass coming for Friday, Saturday, and Sunday with a northern Canada connection**
Paul Dorian
Today is another hot and humid one in the Mid-Atlantic region, but much relief is on the way for Friday, Saturday and Sunday with a refreshing air mass pushing in this direction from northern Canada. Map courtesy NOAA, tropicaltidbits.com
Overview
The Mid-Atlantic region is again suffering with high heat and humidity and temperatures are well up in the 90’s, but much relief is on the way for the end of the week and the upcoming weekend. The current air mass in the Mid-Atlantic region had its origins over the tropical Atlantic Ocean and the air mass headed our way for the late week and weekend will have its roots over northern Canada. Unfortunately, the transition from today’s high heat and humidity to the late week refreshing air mass will feature some shower and thunderstorm activity and some of that rainfall will be heavy at times with flash flooding on the table in some spots; especially, across Maryland, Virginia and the DC metro region.
Today’s hot and humid air mass in the Mid-Atlantic region had its origins over the tropical Atlantic Ocean as displayed on this air trajectory plot. Plot courtesy NOAA
Details
Mid-day temperatures on Tuesday are well up in the 90’s in the DC-to-Philly-to-NYC corridor (1 PM readings: PHL: 95 degrees, DCA: 92 degrees, LGA: 95 degrees) and are likely to peak in the upper 90’s in most spots later in the day. The good news for those suffering in the high heat and humidity is that this will be the worst day of the week and much relief is on the way by the end of the week. The transition from today’s hot and humid conditions to a refreshing air mass at week’s end; however, will not be quiet. Scattered showers and thunderstorms will be around from later today into late Thursday and some of the rainfall will be heavy at times. In fact, flash flooding type rainfall is on the table both on Tuesday night and then again later Wednesday into Wednesday night; especially, to the south of the PA/MD border where the rainfall has been more significant in recent days compared to the northern Mid-Atlantic. An initial frontal system will be the culprit of the unsettled weather conditions from later today into Thursday and then a second and stronger front will sweep through the Mid-Atlantic region on Thursday night.
The refreshing air mass coming this way for the end of the week and weekend will have originated over the northern part of Canada as displayed here on this air trajectory plot with the beginning and end points. Plot courtesy NOAA
The cool frontal passage on Thursday night will usher in a refreshing air mass for the Mid-Atlantic region with comfortable temperatures and humidity levels expected on Friday, Saturday and Sunday. This strong cool front will have enough of a push behind it – namely a strong Canadian high pressure system – to result in this comfortable air mass actually plunging all the way into the southeastern states which isn’t all that common for this time of year. While the upcoming weekend is likely to begin with plenty of sunshine in the Mid-Atlantic region to go along with the nice air mass, it could end on a wet note. A disturbance over the Great Lakes is likely to drop to the south and east later in the weekend and it could generate some shower activity late Sunday and/or Monday in the Mid-Atlantic region, but temperatures will remain at comfortable levels.
Meteorologist Paul Dorian
Arcfield
arcfieldweather.com