1:20 PM | **Some accumulating snow on Friday in parts of the Mid-Atlantic region…frozen precipitation a possibility late Saturday evening in areas north of the PA/MD border**
Paul Dorian
Snow will break out on Friday in the Mid-Atlantic region and small accumulations are possible in the DC-to-Philly corridor and perhaps as far north as NYC; map courtesy NOAA/EMC, tropicaltidbits.com
Overview
Arctic cold continues to have a grip on the Mid-Atlantic region and weak low pressure on Friday is likely to result in a mainly snow event for most areas and small accumulations are possible. Snow is likely to break out on Friday during the mid-day or early afternoon hours in the DC metro region and the early-to-mid afternoon hours in Philly as low pressure pushes towards the North Carolina/Virginia coastline. The NYC metro region may escape with little, if any, snowfall from this weak system on Friday. A more important storm with more available moisture will generate precipitation in the Mid-Atlantic region late Saturday evening and it can be just cold enough at the onset in areas north of the PA/MD border for a period of freezing rain, sleet and/or snow before an ultimate changeover to plain rain. This same system will produce a major snowstorm in the Northern Plains on Saturday and possibly another severe weather outbreak in the Mississippi Valley. Later Sunday, temperatures can climb to 60 degrees in DC, 55 degrees in Philly, and 50 degrees in NYC ahead of a strong cold front which will usher in colder air for the early part of next week.
Precipitation returns by late Saturday evening and it could be cold enough for a wintry mix in some areas north of the Mason-Dixon Line; map courtesy NOAA/EMC, tropicaltidbits.com
Small accumulations likely on Friday
Surface low pressure supported by upper-level energy will push across the Mid-Atlantic region on Friday and snow is likely to break out in the DC-to-Philly corridor with small accumulations on the order of a coating to an inch or so. The snow will have trouble making it as far north as the NYC metro region where little, if any, snow likely will fall. While some rain can mix in at times on Friday; especially, in areas to the south and east of the DC, this looks like primarily a snow event from the suburbs of DC northeastward to eastern Pennsylvania. Precipitation winds down early tomorrow night and Saturday promises to be moderately cold and dry with some sunshine. As far as roads are concerned, it looks like the AM commute will not be affected in DC or Philly and given the daytime snowfall that is expected, minimal problems are anticipated.
Another potentially serious severe weather outbreak is possible on Saturday across the Lower Mississippi Valley and perhaps as far north as the Ohio Valley; forecast map courtesy NOAA/SPC
Frozen precipitation threat late Saturday night/early Sunday
A more important system in terms of total available moisture will head towards the Great Lakes region on Saturday generating significant snow for the Northern Plains where Arctic cold is firmly entrenched and rain/thunderstorms in the storm’s warm sector. Indeed the clash of air masses this weekend is liable to result in another severe weather outbreak on Saturday in the Lower-to-Mid Mississippi Valley with the threat of more tornado activity.
Vigorous energy in the upper atmosphere on Saturday will likely support a severe weather outbreak in the Lower-to-Mid Mississippi Valley; courtesy NOAA/EMC, tropicaltidbits.com
This system will bring precipitation into the Mid-Atlantic region by late Saturday night early Sunday morning and it could be just cold enough at the onset for frozen precipitation in areas north of the PA/MD border. Any wintry mix is likely to change to all rain by Sunday morning in the immediate I-95 corridor and it’ll turn noticeably milder in the afternoon just ahead of the next cold front. That frontal system will usher in colder air the first part for next week.
Meteorologist Paul Dorian
Perspecta, Inc.
perspectaweather.com
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