7:00 AM | ***White-out conditions with heavy snow through the morning; snow ends by early-to-mid afternoon with 3-6 inches of accumulation***
Cloudy and cold with periods of snow, the snow will come down fast and furious for about a 6-hour period during the morning and early afternoon hours, the snow ends by mid-afternoon with accumulations of 3-6 inches, highs in the low 30’s
Becoming partly cloudy, very cold, lows in the upper teens
Mostly sunny, very cold, near 30
Mostly clear, very cold, middle teens
Mostly sunny and very cold, mid-to-upper 20’s
Mostly sunny, cold, mid 30's
Mostly cloudy, cold, chance for rain or snow late, upper 30’s
Partly sunny, windy, cold, snow showers possible, upper 30’s
If you are at work, stay at work; if you are at home stay at home as a wall of snow has moved into the region and it will snow hard through the morning and into the early afternoon hours. This “fast-moving” and "quick-thumping" system will end by mid-afternoon after dumping 3-6 inches of snow on the area. After this storm passes, the Wednesday through Friday time frame will be very cold and dry. A significant storm will then pull out of the Deep South and head towards the Mid-Atlantic coast this weekend, but it is too early to tell if there will be enough cold air around for snow from that next system so rain is a possibility or some kind of mix.
Here we go again for the Mid-Atlantic I-95 corridor region with more accumulating snow on the way. A temperature gradient boundary zone that has been hanging around the eastern states for several days will again act as a conduit for moisture later tonight and Tuesday. This next batch of moisture will move in a southwest-to-northeast fashion reaching the Mid-Atlantic region early tomorrow. Tomorrow’s event should be primarily, if not completely, in the form of snow in Philly and NYC, but there is a chance that the precipitation begins as sleet in the DC metro region before quickly changing to all snow. Precipitation should break out near or just before daybreak in the DC metro region and then in the early-to-mid morning hours across Philly and NYC. This will be a “fast-moving, quick thumping” type of snowfall with a burst of heavy snow in DC during the morning hours, and in the late morning/mid-day hours in Philly and NYC. The snow should then end quickly from northwest-to-southeast by early tomorrow night.
The upper level pattern for this upcoming event is rather impressive with a strong jet streak playing a key role. It appears that the I-95 corridor region will be in the right/rear quadrant region of a strong upper level jet streak which is conducive to upward motion. Snow accumulations should be on average in the 3-6 inch range from DC-to-Philly, and 2-4 inches in the New York City metro region. We’ll have to see if any small-scale heavier snow bands set up on Tuesday which is quite possible given the expected strong dynamics associated with this powerful upper level jet streak. [12Z NAM 300 millibar winds forecast map for early Tuesday depicting the strong upper level jet streak at 150+ knots across the Northeast US (purple region)].
A few notes about yesterday's snowfall in Philly...Philly Int’l Airport officially recorded 8.6 inches which was only the 8th time in which 8 inches or more has fallen in the month of December and 3 of those 8 events have occurred in just the last 5 years. Also, yesterday's 8.6 inches of snow at PHL was more than recorded for the entire 2012-2013 winter season.
Finally, another storm threatens the Mid-Atlantic region this weekend with more significant snow and/or rain possible.
Cloudy and cold with occasional rain or drizzle, highs in the upper 30's
Cloudy and cold, lows in the upper 20’s, watch for slippery spots on untreated surfaces
Cloudy, cold, periods of snow with several inches possible by tomorrow night, low 30’s
Becoming partly cloudy, very cold, upper teens
Mostly sunny and very cold, near 30
Mostly sunny and still very cold, upper 20’s
Partly sunny, very cold, low 30’s
Mostly cloudy, cold, maybe snow showers, low 30’s
Slightly milder air moved in overnight changing our wintry precipitation to plain rain and we'll continue to have some light rain or drizzle for part of the day. More moisture to our southwest will ride up an old frontal boundary zone on Tuesday in a southwest-to-northeast fashion and it looks like it'll be cold enough for all snow for this event across the Philly metro region. Snow is likely to begin during the early-to-mid morning hours on Tuesday and continue for much of the day with preliminary accumulation estimates on the order of 3-5 inches. Once this next system passes by, the second half of the week will be dry and very cold for this time of year.
A few notes about yesterday's snowfall in Philly...the Philly Airport officially recorded 8.6 inches which was only the 8th time that 8 inches or more has fallen in the month of December and 3 of those 8 events have occurred in the last 5 years. Also, yesterday's 8.6 inches was more than PHL recorded all of last winter.
The first accumulating snow of the season has arrived in the DC metro region and it will move into the Philly metro region by late morning or early afternoon and then reach New York City by late afternoon or early evening. The general scenario at all three metro regions will be for a several hour period of accumulating snow followed by a several hour period with icing (i.e., sleet and/or freezing rain) and this will add a layer of ice on top of the snow. Finally, enough milder air will move in to change all of the precipitation to plain rain later tonight and early Monday from the immediate I-95 corridor to the coast. Areas north and west of I-95 will see a longer period of frozen precipitation perhaps into the early morning hours on Monday.
Snow accumulations of 2-4 inches can be expected across the DC metro region and I believe this 2-4 inch range, perhaps even isolated 6" amounts, will extend northward to the region between Philly and New York City based on current radar observations which suggest a heavier band of snow will set up later today in that region. Travel conditions will deteriorate for an extended period of time into the overnight hours in all three metro regions given the accumulating snow and ice and with surface temperatures holding at or below the freezing mark. By tomorrow morning, plain rain should help to improve travel conditions along I-95 and to the coast. Stay tuned, tricky forecast.
One final note, there will be snow and/or bitter cold across the board today for the NFL in places like Philly, Baltimore, DC, Green Bay, Denver, etc., etc.