WEATHER BLOG: Warm Temps Continue...For Now
A front separating an exceptionally warm and humid air mass from a cooler air mass remains draped from the northern Mid-Atlantic Coast to the U.S. Southern Plains. Numerous "waves" of low pressure can be found traveling along this boundary. These waves are accompanied by large swathes of cloud cover and rain.
The first wave of low pressure is currently passing off the New Jersey Coast. In the wake of the low, the front is bowing southward and cooler air is filtering into the area. As the low pulls out to sea, the showers will depart the area and cooler air will arrive for Saturday. Instead of highs in the 60s, temperatures will only reach the 50s today. Although the deep moisture from this low will have left the region, the proximity of the boundary in combination of a moist easterly flow of air off the Atlantic will keep skies cloudy and promote occasional drizzle and a passing shower or two. Locally dense fog will also occur.
Later today and tonight, another "wave of low pressure" on the front will move from the mid-Ohio Valley to western PA. This will bring some light rain to the region late in the afternoon into the evening. Temperatures will remain steady beneath the cloud cover. As the wave of low pressure draws closer to the region, winds will shift and blow from the southeast and south allowing temperatures to slightly rise toward daybreak on Sunday.
On Sunday, this second wave of low pressure will move into southern New England. This will allow winds to shift and blow from the southwest and direct warmer and drier air into the region for a brief time. A few breaks of sunshine will occur, which will allow temperatures to once again reach record levels (in the low 70s). By late afternoon/evening on Sunday, the low will pass off the southern New England Coast and send a cold front through the Tri-state/Lehigh and Delaware Valleys and a few widely separated showers will accompany this front. Heavy rain is unlikely with the frontal
passage since the upper-level energy associated with the accompanying low pressure is rather weak.
Drier and colder air will sweep into the region on winds form the northwest and north overnight Sunday and into early Monday as a cold high pressure system slides east across Ontario Canada. Under partially clearing skies, temperatures overnight Sunday will fall into the low to mid 40s.
On Monday, a more formidable wave of low pressure on the aforementioned front will get ejected northeast from into the Ohio Valley from Texas (incidentally, this system will bring severe storms and heavy snow to parts of the southern Plains and Deep South). At the same time, the cold high pressure over southeastern Canada will filter seasonable chilly (not arctic) air into the Mid-Atlantic States. This will keep high temperatures on Monday relatively low (by comparison to recent days) in the 40s.