The National Weather Service Baltimore MD/Washington DC has indicated that high pressure from the Plains is set to steadily build over the area, ushering in a weekend of clear skies and cool temperatures. According to their latest update, this system will persist into next week, when it will give way to a low-pressure system advancing from the Mississippi River Valley.
The forecast anticipates cool and dry conditions for the present, with west gusts reaching up to 30 knots in the Alleghenies. This may lead to sporadic light rain showers; however, elsewhere in the region is expected to remain dry, the National Weather Service reports. High temperatures today are predicted to hover in the 50s to low 60s, except in the Alleghenies, where the mercury isn't likely to break out of the 40s.
As for tonight, the skies are slated to remain mostly unclouded. This minimal cloud cover, in harmony with light winds, is expected to enable radiational cooling to take full effect, driving overnight temperatures down into the 30s across the region. Some areas might even witness temperatures plunging into the upper 20s, casting the areas of central and northern Virginia under a Frost Advisory and Freeze Warning, as these locales endure an ongoing growing season.
Friday will see the winds shift to a northerly direction, in the wake of a weak front, yet the dryness will persist into Saturday as high pressure firmly plants itself over the region. Highs are again projected to be in the comfortable bracket of 50s and 60s, with another chilly spell expected Friday night, where Frost and Freeze watches may once more become necessary. Saturday night's lows will also tend to be on the cold side, with temperatures predicted to lurk in the 30s to low 40s.
In the longer view stretching from Sunday through Wednesday, expect the high-pressure system to linger, supporting more dry conditions. The daytime temperatures are forecasted to climb back to closer seasonal averages towards the end of this time frame, following an initial period where highs will stay in the 50s to low 60s and lows will maintain their grip in the 30s.
For aviators, the outlook through Monday is bright, with VFR (Visual Flight Rules) conditions forecasted every day due to the high-pressure influence. Marine conditions, too, seem mostly moderate, though there's a Small Craft Advisory in effect for certain areas today due to gusty west winds.
Regarding fire weather, the National Weather Service cautions that the combination of gusty westerly winds and potentially very low relative humidity (RH) values could enhance the risk of rapid fire spread this afternoon, specifically targeting portions of the Virginia Piedmont for this advisory.
