7:30 AM (Sunday) | ****An Arctic blast arrives today…temperatures to plunge with a potential quick freeze…single digits by early Monday…scattered power outages a threat****

00Z NAM forecast map of surface temperatures as of Monday morning (7AM); courtesy NOAA, tropicaltidbits.com

Overview

Arctic air will flood the Mid-Atlantic region today on the backside of departing low pressure which caused heavy rain in the I-95 corridor during the overnight hours.  Temperatures will plunge from mid-day through the afternoon and any residual wet surfaces could quickly freeze potentially creating hazardous driving conditions.  Single digit lows are likely throughout the I-95 corridor by early Monday and wind chills will make it feel painfully cold.  The threat for scattered power outages later today and tonight cannot be ruled out as winds could gust past 40 mph or so.

00Z NAM surface forecast map as of Sunday evening (7 PM); courtesy NOAA, tropicaltidbits.com

Discussion

Strong low pressure and its associated cold frontal system will push through the I-95 corridor later this morning and the flood gates will be opened for an Arctic air mass to pour into the region.  There may be a brief period of ice or snow as the front pushes through the region during the late morning or mid-day hours. The influx of Arctic air will cause temperatures to drop sharply and winds will pick up in intensity out of the N-NW.  Any slush or residual wet surfaces will freeze rather quickly later today and the plunge in temperatures will continue on Sunday night. Overnight lows could end up in the lower single digits by early Monday – easily the coldest day of the season so far – and highs on Monday will do no better than the teens along with a biting wind (wind chills of -10 to -20 degrees).  In fact, there is an outside shot at 0 degrees for the low temperature in many spots by early tomorrow morning. One of the reasons this Arctic air mass will be so cold around here is the fact that it’ll be coming from the continental part of southeastern Canada and not able to get modified by the more typical crossing of the relatively warm (still not completely frozen) Great Lakes. One final note of concern, the intensification of the winds to 40 mph or so later today into Monday morning as the Arctic air pours into the region may not work too well with potentially ice-covered branches and limbs (i.e., possible scattered power outages).

00Z NAM forecast map of surface temperatures as of Sunday evening (7 PM); courtesy NOAA, tropicaltidbits.com

Meteorologist Paul Dorian
Perspecta, Inc.
perspectaweather.com