12:50 PM | *Accumulating snow threat continues for Thursday night/Friday*
Paul Dorian
12Z GFS forecast map for early Friday afternoon (blue=snow, green=rain); map courtesy tropicaltidbits.com, NOAA
Thursday night/Friday accumulating snow event
Strong NW winds have flooded the Mid-Atlantic region today with a much colder air mass compared to the past couple of days and this will set the stage for an accumulating snow event tomorrow night and Friday. After a very chilly night, clouds will increase later tomorrow as moisture begins streaming eastward from the Ohio Valley with low pressure dropping into the region from the Northern Plains. Snow should break out tomorrow night in the I-95 corridor and continue into Friday with accumulations likely for the Friday morning commute. Rain can mix in at times during this event; primarily, to the southeast of I-95.
By Friday morning, the initial Ohio Valley low pressure system will transfer its energy to a secondary low pressure system along the Mid-Atlantic coastline and this storm is expected to intensify rapidly as it pulls northeastward to the point where it could produce near hurricane-force winds by late Friday. As far as preliminary snowfall estimates are concerned, certainly up to 3 inches of snow can fall in the DC, Philly, and NYC metro regions, and a slight shift to the northwest in the current expected storm track would increase accumulations significantly along the I-95 corridor - so stay tuned. In the last 24 hours, the European model has indeed shifted to the north with its placement of the coastal low as of Friday morning (below) and it is also now a bit stronger - we'll see if this trend continues which would not be all that unusual for wintertime coastal storms in the eastern US.
24 hour change in the European model forecast of the coastal low for Friday morning (left from Tuesday morning's model run, right from Wednesday morning's model run); maps courtesy tropicaltidbits.com
"Clipper" snow threat and then a major warm up next week
Relatively cold conditions are likely to continue through the upcoming weekend following the late week accumulating snow event and there can even be more snow or snow showers in parts of the Mid-Atlantic region by Saturday night from a “clipper” low pressure system (circled on forecast surface map) dropping southeastward from the Northern Plains. Beyond that, there are signs for a significant warm up next week that could cause temperatures to reach the 60 degree mark by Tuesday afternoon in much of the I-95 corridor and then to 70 degrees later in the week. One final note of interest, this volatile March weather pattern over the next few weeks is likely to generate tons of rain for California along with higher-elevation snows.
Meteorologist Paul Dorian
Vencore, Inc.