7:00 AM | *Wet snow accumulations on Friday...Arctic blast for the weekend...another storm threat by Tuesday*
Paul Dorian
6-Day Philly Forecast
Today
Mainly sunny, still windy and quite mild, highs near 60 degrees
Tonight
Becoming cloudy and turning colder, rain develops after midnight and likely changes to sleet for a brief time before finally changing to snow by morning, near 32 degrees by daybreak
Friday
Snow likely in the morning then remaining mostly cloudy during the afternoon with an additional snow shower or two, maybe even a snow squall, windy, quite cold, upper 30’s for highs
Friday Night
Becoming partly cloudy, breezy, quite cold, upper teens for lows
Saturday
Mainly sunny, brisk, very cold for this time of year, near 30 degrees for highs (normal high at PHL is 50 degrees)
Sunday
Partly sunny, still very cold for this time of year, low 30’s
Monday
Increasing clouds after morning sun, cold, mid-to-upper 30’s; chance for snow at night
Tuesday
Mainly cloudy, breezy, cold, chance for snow, mid 30’s
Discussion
There are three different low pressure systems to monitor for the period extending from later tonight into the middle part of next week and accumulating snow is certainly on the table, but perhaps the biggest story of all could be the impressive Arctic blast that is coming for the weekend. Air trajectory maps show that the air coming into the Mid-Atlantic region for the weekend has its origins in the Canadian Arctic where they have experienced some of the coldest March weather in decades. An Arctic front will slide through the Mid-Atlantic region on Friday – accompanied by strengthening low pressure – and its passage will usher in air that will likely be some 15-20 degrees below normal for this time of year.
The low pressure that forms along this Arctic frontal boundary zone later tonight will generate rain at first in the region, but then as colder air filters in from the north, a changeover to snow is likely from north-to-south by early tomorrow. Snow is likely to continue tomorrow morning and it can be mixed with rain at times and then there can be a few afternoon snow showers - perhaps even a heavier snow squall. Accumulations on the order of a coating to an inch or two are possible on Friday; primarily, on non-paved surfaces. After Arctic cold air overtakes the area on Friday night and Saturday, the next storm system will be suppressed well to the south - sparing the region of any late weekend snowfall. A third system is likely to develop in the Mid-Atlantic region in the late Monday night or Tuesday time frame and it could intensify rapidly near the coastline with lots of cold air in place - in other words, lots of potential.
Meteorologist Paul Dorian
Vencore, Inc.
vencoreweather.com