12:00 PM | **Clipper/front impacts the region later today, early tonight...significant snow threat later Sunday into Monday**
[12Z Euro 96-hour forecast for Monday morning; map courtesy WSI]
Overview There are two systems that are likely to spread wintry precipitation into the I-95 corridor over the next few days. The first system will be limited in moisture; however, it still can produce some slippery spots later today and early tonight. The second system will have lots of moisture to work with, lots of cold air in place as it arrives, and it has the potential to produce several inches of snow around here from late Sunday into Monday.
Late today, tonight – the clipper system and its associated cold front The first system is a clipper type of low pressure that is currently located over the eastern Great Lakes and it will drag a cold front across the region in the overnight hours. This system will not produce much precipitation in the I-95 corridor, but there can be enough for some slippery spots given the cold ground conditions.
In DC, the timing is not good as the precipitation is likely to arrive by 3PM or so and primarily be in the form of sleet although freezing rain and snow can be mixed in. This evening’s commute in the DC metro region is likely to see slippery spots on the roadways associated with this upcoming wintry mix. North of the PA/MD border, precipitation should primarily be in the form of snow; however, even that far north, there can be some sleet mixed in at times. The snow or snow/sleet mix should arrive in Philly by 5pm or so, and then in NYC around 8pm or so. The latter stages of the evening commute in Philly can certainly be affected by the weather, but the NYC rush hour should expire before precipitation arrives up there. Snow accumulations in Philly and NYC can end up in the “coating to an inch or two” range by later tonight.
This clipper system will then intensify rapidly late tonight and it will have a much bigger impact on northern New England. Areas north of the Massachusetts Turnpike (e.g., New Hampshire and Maine) will likely get hit by several inches of accumulating snow and strong winds – something they really don’t need. Winds will get quite strong around here tomorrow and tomorrow night resulting in very low wind chill values and the actual air temperatures could drop into the single digits in some areas late tomorrow night. Saturday stays on the frigid side around here with highs confined to 20’s at best.
Late Sunday into Monday - a significant snow threat for the I-95 corridor Over the weekend, copious amounts of moisture will head out of the southwestern states and into the central Plains and then right towards the Mid-Atlantic region. Significant snow is likely first in New Mexico (tonight, Friday) and then from Kansas to Illinois on Saturday. By Sunday, this moisture will begin streaming into the Mid-Atlantic region and snow is likely to be the result. Quite cold air will be in place in the Mid-Atlantic with anchoring high pressure systems situated to the north and northwest. This storm has the potential to produce several inches of snow late Sunday into Monday in the entire I-95 corridor region from DC-to-Philly-to-NYC and also throughout much of the region between I-80 and I-70. It is still a few days away; however, and - as we experienced earlier this week - a slight shift in the pattern can have significant impact on the outcome. No matter what happens with this early week storm, bitter cold air is likely to follow for much of next week.