12:20 PM | **Unusual cold continues into next week…some snow likely on Saturday, but not looking significant**
Paul Dorian
06Z GEFS forecast map of 2-meter temperature anomalies for Saturday afternoon with way below-normal conditions across a widespread part of the nation; courtesy NOAA/EMC, tropicaltidbits.com
Overview
An active and cold weather pattern will continue for the Mid-Atlantic region into the middle of next week with additional cold air outbreaks and the threat for more early spring snow. After a blustery and cold day today, a “clipper-like” low pressure system will drop southeastward across the Great Lakes on Friday and it will bring some rain and snow shower activity to the Mid-Atlantic region. This system will drag a cold front through the area and much colder-than-normal air will flood the region for the weekend after a brief warm up on Friday afternoon. A wave of low pressure will form along this cold frontal boundary zone and likely throw some snow into the I-95 corridor on Saturday, but it doesn’t appear to be a significant event. Yet another low pressure system may impact the Mid-Atlantic region in the early part of next week.
Details
Today happens to be the home opener for the Nationals in DC and Phillies in South Philadelphia and it won’t exactly be great baseball weather this afternoon for those games with winds making it feel even colder than the actual air temperature which is well below normal for this time of year. On Friday, a “clipper-like” low pressure system will trek southeastward across the Great Lakes and it'll push some rain and snow shower activity into the I-95 corridor late tonight and early tomorrow and there can even be a coating of snow in some spots north of the PA/MD border. A cold front will trail from the low pressure system and its passage will usher in much colder air for the weekend which will be way below-normal for this time of year - perhaps as much as 20-25 degrees below-normal (normal high now is 60 degrees at PHL, 57 degrees in Central Park, NY, and 63 degrees at DCA).
12Z GFS surface forecast map for early Saturday morning (8AM) with snow shown in blue and sleet/freezing rain in pink.purple; map courtesy NOAA/EMC, tropicaltidbits.com
This cold frontal system will stall out just to the south and east of here by Saturday and a wave of low pressure will form along the frontal boundary zone and ride to the northeast. With the influx of the very cold air, temperatures will likely become supportive of snow all the way down into the DC metro region, but the precipitation could start out as rain or a wintry mix towards morning early on Saturday.
In terms of snow accumulations, while it does appear that it will get cold enough for snow, it is not looking like a significant event with perhaps the best early estimate being a "coating to two or three inches" in the DC-to-Philly-to-NYC corridor (lower amounts in that range in NYC and the higher amounts in DC). There are still some details that have to be ironed out as far as accumulations are concerned as, for example, it is a bit early to pinpoint the exact storm track and timing of the changeover to snow. In addition, the eventual strength of tomorrow’s "clipper-like" system will also play a role in the Saturday event as a stronger "front running" system on Friday could sap some energy from the following second wave of low pressure and also push the frontal boundary zone farther to the south and east; thereby, having even less impact on the DC-to-Philly-to-NYC corridor. After a cold day on Sunday, yet another low pressure system may head towards the Mid-Atlantic coastline and it could impact the I-95 corridor with rain and/or snow early next week.
Meteorologist Paul Dorian
Vencore, Inc.
vencoreweather.com
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