3:20 PM | *Showers/storms this evening...soaking rain event begins this weekend for an extended period*
Paul Dorian
Scattered showers and storms at mid-afternoon as cold front approaches the I-95 corridor; courtesy University of Wisconsin
Overview
There will be scattered showers and thunderstorms later this afternoon and tonight in the DC-to-Philly-to-NYC corridor as a cold front approaches and some of it will be on the heavy side; especially, south of the PA/MD border. This rain event will be relatively short-lived compared to what is coming later this weekend and early next week. Following tonight’s cold frontal passage, weak high pressure will try to get us off to a decent start this weekend, but it will be facing long odds as low pressure will head our way from the Lower Mississippi Valley. Rain is likely to return to the Mid-Atlantic region late in the day tomorrow or early tomorrow night and then continue off and on into Tuesday of next week. The heaviest rainfall may come in two parts with one period centered on tomorrow night into Sunday morning and then a second phase from late Sunday into Monday. Residual showers may very well last into the day on Tuesday in the Mid-Atlantic region.
Short-term (late Friday through Saturday)
Temperatures have jumped well up into the 70’s across the I-95 corridor ahead of an approaching cold front and there are bands of showers and embedded thunderstorms to our west. Scattered showers and thunderstorms will impact the region north of the PA/MD border during the latter part of the afternoon and throughout the evening and it is possible for some of the rain to be briefly heavy. South of the Mason-Dixon Line, the radar echoes are much more impressive with the approaching cold front and it appears that the DC metro region will get pounded with some heavy rainfall during the next couple of hours as a solid line treks from west-to-east across the metro region…expect wind gusts to 40 mph and downpours with this line of storms in and around the District.
Once the cold front clears the coast, it will tend to slow down and then stall out across the southern Mid-Atlantic setting the stage for more unsettled weather later in the weekend. There may be a bit of sunshine early tomorrow north of the PA/MD border, but clouds will likely be stubborn across the DC metro region. It’ll also turn cooler in all areas on Saturday on the backside of this evening’s cold frontal passage.
Soaking rain event (Saturday night into Monday)
An upper-level low will intensify as it makes its way from the Dakotas to New England this weekend. An initial surface low will move from the Lower Mississippi Valley to the eastern Great Lakes later tomorrow and rain is likely to return during the late afternoon in DC, early tomorrow night in Philly and late tomorrow night in NYC. The period from tomorrow night into Sunday morning can feature some heavy rainfall and maybe a thunderstorm or two. Sunday will be quite cool for this time of year with highs likely confined to the 50’s across PA and low-to-mid 60’s in the DC metro region.
The rain could diminish some later Sunday, but don’t expect any clearing as it’ll stay damp and cool ahead of another round of rain that is destined for the Sunday night into Monday time period. In fact, with the slow movement of the upper-level system, lingering showers could last into Tuesday of next week.
Meteorologist Paul Dorian
Perspecta, Inc.
perspectaweather.com
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