1:50 PM | **A quick burst of snow possible this afternoon, frozen precipitation later tonight north of the PA/MD border, powerful mid-week winds, and possible weekend snow**
Paul Dorian
12Z GFS-FV3 forecast map for Sunday morning with low pressure organizing off the NC coastline and snow (in blue) in much of the Mid-Atlantic region; map courtesy NOAA/EMC, tropicaltidbits.com
Overview
The last couple of weeks were well above-normal in the eastern half of the nation, but this week will be a lot different with noticeably colder conditions. In addition, winds will become quite a factor as they will become quite strong on Wednesday and Thursday with gusts to 50 mph likely in the DC-to-Philly-NYC corridor. As far as precipitation is concerned, a quick burst of snow is possible this afternoon and frozen precipitation is a threat later tonight; primarily, in areas to the north of the PA/MD border. Looking ahead, snow is on the table this weekend in the Mid-Atlantic region as a storm tries to get going near the eastern seaboard.
Warmer-than-normal conditions persisted during the past two weeks in the eastern half of the nation, but temperatures will be below-normal this week; map courtesy Weather Bell Analytics, NOAA
This afternoon through tomorrow night
Very cold air dropped southward yesterday through New England and into the Mid-Atlantic region – all anchored by strong high pressure over southeastern Canada. Meanwhile, an intensifying low pressure system is trekking east across the Great Lakes and it’ll bring some precipitation to the Mid-Atlantic region later tonight into early Tuesday. In fact, there is a band of snow and sleet cutting across Pennsylvania at this hour – well ahead of the main system – and this could result in a quick burst of snow this afternoon perhaps mixed with sleet; primarily, in areas north of the PA/MD border. Later tonight, steadier precipitation will arrive and it should be cold enough north of the Mason-Dixon Line for snow initially and then a wintry mix of snow, sleet and rain which could result in slick spots towards morning along with small accumulations of snow and ice. In the DC metro region, this nighttime precipitation is likely to fall as plain rain though ice pellets may mix in across the far northern suburbs of the District.
After a milder day on Tuesday with high temperatures approaching or slightly surpassing the 50 degree mark, a strong cold front will sweep across the Mid-Atlantic region tomorrow night. Rain showers are likely to accompany this frontal passage although some flakes and ice pellets cannot be ruled out late tomorrow night in areas north of the PA/MD border as colder air pours into the region on increasingly strong NW winds.
12Z GFS-FV3 forecast map for Wednesday afternoon with a tight pressure gradient in the Mid-Atlantic region which could result in wind gusts to 50 mph; map courtesy NOAA/EMC, tropicaltidbits.com
Wednesday/Thursday
Very cold air will flood the Mid-Atlantic region at mid-week in the wake of Tuesday night’s frontal passage and winds will become very strong. In fact, winds could gust to 50 mph on Wednesday and Thursday in the DC-to-Philly-to-NYC corridor with scattered power outages a real possibility. A a tight pressure gradient will form here by Wednesday between intensifying low pressure over New England and strong high pressure to our northwest. Temperatures on Wednesday and Thursday will be well below-normal for this time of year and strong winds will make it feel even colder than the actual ambient temperature would suggest.
Weekend snow threat
By the weekend, low pressure will be gathering strength over the Gulf of Mexico at the same time strong, cold high pressure will slide east across south-central Canada. The upper atmosphere will feature two waves of energy to monitor this weekend – one in the northern stream over the Great Lakes by Saturday and the other down in the southern US. It is too early if these two upper-level waves of energy will phase in time for a strong storm to form near the Mid-Atlantic coastline this weekend. If this were to happen, significant snow could be the result in at least parts of the Mid-Atlantic region…stay tuned.
Meteorologist Paul Dorian
Perspecta, Inc.
perspectaweather.com
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