2:20 PM | ****Arctic air mass drops south to Texas then shifts east…reaches I-95 corridor late morning/mid-day on Friday...plunging temperatures, damaging winds, flash freeze, burst of snow****
Paul Dorian
A plunge in temperatures will follow immediately the passage of a powerful Arctic surface front in the DC-to-Philly-to-NYC corridor in the late morning/mid-day hours on Friday. This loop of actual surface air temperatures extends from Friday morning (December 23rd) to Monday morning (December 26th). Maps courtesy NOAA, tropicaltidbits.com
Overview
The core of an intensely cold Arctic air mass is now getting ready to plunge southward to Texas by later tomorrow and then it’ll shift to the eastern states on Friday. Numerous low temperature records are likely to be set over the next couple of days as this air mass makes its way across the nation. Blizzard conditions will accompany this advancing Arctic air outbreak over much of the eastern half of the country with the Great Lakes region likely to experience some of the worst weather with an extended period of extreme conditions from Friday into late weekend.
The powerful Arctic frontal system that represents the leading edge of this intensely cold air mass will reach the DC-to-Philly-to-NYC corridor during the late morning/mid-day on Friday. Temperatures will drop dramatically in the wake of the frontal passage some 30+ degrees in a short period of time. Any wet spots on roadways from prior rainfall could freeze-up in a hurry. There will be very strong wind gusts on Friday and a burst of snow is likely immediately behind the frontal passage that can produce a quick coating to an inch or two. A frigid weekend will follow with Christmas Eve (Saturday) and Christmas Day (Sunday) the coldest in many years across much of the eastern half of the nation. Single digits are likely in many spots along the I-95 corridor both on Saturday and Sunday mornings.
A widespread and intensely cold Arctic air mass will dominate the scene as we reach the Christmas weekend throughout the eastern half of the nation. This forecast map of 850 mb temperature anomalies is for early Saturday morning, Christmas Eve from the 12Z GFS model run. Map courtesy NOAA, tropicaltidbits.com
Major and widespread Arctic air outbreak
A major and widespread Arctic air outbreak has reached the northern US from the Pacific Northwest to the Northern Plains and the core of this cold air mass is about to take a plunge to Texas during the next 24 hours or so. This intensely cold air mass will likely result in numerous low temperature records over the next couple of days as it expands across the central and eastern US. This frigid cold air mass had its origins on the other side of the North Pole over Siberia and “cross-polar” flow has allowed it to be transported from there to northwestern Canada and now into the northern US.
A soaking rain event is in store for the Mid-Atlantic region from early Thursday into early Friday - all out ahead of the Arctic front - and this storm may include some thunderstorm activity as well. Map courtesy NOAA, tropicaltidbits.com
Mid-Atlantic soaking rain event from early Thursday into early Friday
On Thursday, strong low pressure will develop in the eastern US and it will push much milder air into the Mid-Atlantic and Northeast US on increasingly strong S-SE winds. There is a chance that enough cold air will be lingering around early on Thursday to result in a brief period of snow and/or ice in some of the northern and western suburbs along the I-95 corridor; however, temperatures should climb to well above freezing levels by later in the day. The rain can indeed fall heavily at times from later Thursday into Friday morning and a thunderstorm or two cannot be ruled out in this soaking rain event. This surge of mild air will likely peak on Friday morning with temperatures near 50 degrees in some spots, but that warmth will disappear abruptly later in the morning or early in the afternoon on Friday.
A powerful Arctic front will blast through the DC-to-Philly-to-NYC corridor by late morning or mid-day on Friday and its passage will be quite dramatic with a plunge in temperatures, strong wind gusts, a possible “flash-freeze” and a burst of snow that can produce a quick coating to an inch or two. Map courtesy NOAA, tropicaltidbits.com
Powerful Arctic frontal passage by late morning or mid-day on Friday in DC-to-Philly-to-NYC corridor
By late morning or mid-day on Friday, the leading edge of this intensely cold Arctic air mass will reach the Mid-Atlantic’s I-95 corridor. The powerful Arctic surface front will have quite a dramatic passage with strong and potentially damaging winds shifting to a W-NW direction, plunging temperatures as much as 30+ degrees in just a couple of hours and this can cause a quick freeze-up or “flash freeze” of any lingering wet spots on roadways from the prior rainfall. In addition, there can be a burst of snow in the immediate aftermath of the frontal passage potentially producing a quick accumulation of a coating to an inch or two adding to the potential difficult travel conditions.
Temperatures will continue to drop sharply on Friday night and the weekend promises to be frigid not only in the Mid-Atlantic region, but throughout the eastern half of the nation. In fact, this will likely turn out to be the coldest Christmas Eve (Saturday) and Christmas Day (Sunday) in many years in the eastern half of the country. Single digit temperatures are likely along the I-95 corridor both on Saturday morning and again on Sunday (Christmas) morning. Winds will remain quite strong all weekend long making it quite difficult for the lighting of luminaries in those neighborhoods that follow that tradition. In terms of a follow-up thaw in the eastern US, it is pretty much inevitable that temperatures will become noticeably milder later next week as this incoming Arctic air mass in the central and eastern US will actually be some of the coldest air in all of North America. The thaw can then continue into the first week of January as well while the atmosphere begins to “re-load” with the formation of additional cold air masses upstream.
Meteorologist Paul Dorian
Arcfield
arcfieldweather.com
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