By John Cifelli
NJTV News Meteorologist
Wings are in the oven, wine is in the fridge, but the party is on ice for meteorologists across the northern mid-Atlantic as several days of wintry weather are in store beginning late tonight. It’s a super difficult forecast, with several weak upper level systems bowling through the area, none of them particularly inclined to seize the reins and drive the forecast.
Currently, it’s too warm for snow everywhere. Where the air is more saturated, down the shore, temperatures are actually colder than where the humidity is lower, in the usually colder northwest corner of the state. A powerful coastal low is slowly moving northeast away from the Carolinas, spreading an impressive moisture plume up the entire eastern seaboard all the way to Nova Scotia. This low will rapidly deepen as it slides northeast, and scrape coastal New Jersey after midnight tonight. Through the evening, winds will turn northerly and cool the column of air aloft, allowing most if not all precipitation to fall as snow. Expect an inch or two of accumulation along the Parkway corridor, mostly on unpaved surfaces. The morning commute will be hampered by nuisance snows, but delays shouldn’t be significant. Light snow tapers to flurries by mid-morning.
That’s the easy part of the forecast. The hard part is what comes next. An upper level trough over the Great Lakes slides southeastward toward New Jersey on Monday and deepens, spawning a second coastal low just south of New Jersey. A surface low associated with one of the other aforementioned upper level vorticity maxima will weaken over Pennsylvania or New York, creating a somewhat rare weather phenomenon called an “inverted trough.” In these setups, persistent low level easterly winds will siphon moisture off the ocean and funnel it back through the trough extending back toward the weakening inland surface low. These setups happen once every winter or two, and usually result in a persistent band of steady snow, 50 miles or so in width, that can drop significant accumulations in localized areas, oriented east to west in New Jersey. As is typical with these mesoscale, localized weather features, we don’t have the tools to understand where exactly an inverted trough will set up and cause a high level impact until very close to when it will occur.
For now, the forecast is as follows. Monday will remain mostly cloudy after snow tapers off in the morning. Temperatures will stick near freezing, and after nightfall, snow will restart — south and west first, then further northeast. Snow continues into Tuesday, ending in the late morning in southern New Jersey, and lingering longer, perhaps until nightfall for northern New Jersey. Again, an inverted trough has the potential to focus a narrow band of heavier snow, and where this sets up will see a high impact snowfall for much of Tuesday. By Wednesday, we are slowly clearing out, but anther upper level impulse could trigger a few rounds of flurries or snow showers, without accumulation. Best estimates for Monday night and Tuesday snow totals are one to three inches south of 195 and three to six inches north of 195. For now, I think the inverted trough focuses the best snows into northern Monmouth, Staten Island, Middlesex, Union and Hundson counties. Those who wind up under this band could see accumulations approach double digits. Check back tomorrow for updated thoughts, as things come into better focus.
As for the big game — Carolina 24, Denver 17.