WEATHER NEWS: Tax Day storm to plaster Northeast with inland snowfall

“This late season snowfall is likely to be quite heavy and wet, and could produce significant impacts,” the National Weather Service wrote. “This includes possible downed trees, power outages, and difficult shoveling. Hazardous travel conditions may develop due to the slushy, snow-covered roads.”

The zone from northeast Pennsylvania to central New York state is of particular concern for power outages due to potential snowfall rates of 1 to 3 inches per hour Monday night.

Snowfall totals will be heavily elevation-dependent, with mountainous areas seeing the heaviest amounts.

Blizzard delivers record April snowfall in northern Plains

The same overarching storm system may bring isolated severe weather to the Outer Banks of the Carolinas in its “warm sector,” with a brief tornado or two possible.

A center of low pressure was pushing through Middle Tennessee during the morning hours Monday, with a counterclockwise swirl of clouds visible on satellite imagery. Light snow was falling to the north over portions of the Great Lakes with rain to the east.

That low, energized by an upper-air disturbance arriving from the west, will transfer its energy to a new low developing near the North Carolina coastline late Monday. On Monday night, it will work up the Mid-Atlantic coast and reach southern New England by Tuesday morning.

Lows spin counterclockwise in the northern hemisphere, which is why extreme eastern North Carolina, essentially the Outer Banks, will end up with a sliver of mild air streaming north ahead of a cold front. A change of wind speed and/or direction with height, known as wind shear, could foster some rotation within a couple thunderstorms. A level 1 out of 5 “marginal risk” of severe thunderstorms has been hoisted along the immediate coastline from Charleston, S.C., to Cape Hatteras.

Behind the low west of the system’s track, northerly winds will drag frigid air south from Canada. Moisture overlapping with near-freezing conditions will deposit a strip of snow inland from the West Virginia-Virginia border to Quebec and Ontario.

Storm timing and predicted snow totals

Rain arrived in the nations’ capital from the southwest before noon Monday, mixing with a bit of sleet, but snow was developing in parts of the Blue Ridge and the Allegheny Range. Snow could be moderate to heavy for a brief time during the afternoon before it tapers off around 5 or 6 p.m. south of the Mason-Dixon Line. Around 2 to 4 inches of snow could fall in the mountains of western Maryland and northeast West Virginia as well as the Blue Ridge in Virginia. Locally higher amounts are even possible near mountain peaks.

Many areas of western and west central Pennsylvania will also see accumulating snow, particularly in the higher terrain. Up to 3 to 6 inches are possible there Monday afternoon and night.

Southeast Pennsylvania will see mostly rain between late Monday morning and Monday night, but snow is probable in the Poconos in the northeast part of the state, which are under a winter storm warning for up to 4 to 8 inches through early Tuesday.

In New York City, rain will develop Monday night and will last until a little before sunrise, totaling almost an inch. Boston will see their heaviest rain from midnight to about 8 a.m. Tuesday, with perhaps a clap of thunder or two to the southeast over Cape Cod.

Heavy snow is also anticipated in interior portions of New York state, particularly near and just east of Interstate 81. Winter storm warnings are in effect there, with the Weather Service warning that heavy snow could impact the morning commute Tuesday. A general 4 to 8 inches are likely, with isolated amounts to nearly a foot, mainly above 2,000 feet in elevation.

“We are growing increasingly concerned about the potential for power outages and very difficult travel across central New York and northeast PA,” the Weather Service office in Binghamton, N.Y., tweeted. “The snow is expected to be heavy and wet, with the potential for rates as high as 3” per hour overnight tonight.”

Regardless of total accumulation, snowfall to that degree is extremely difficult or impossible for road crews to keep abreast of. Some thundersnow is possible too.

Up to a few inches of snow are also probable in Vermont, although the coastal storm may draw enough warm air into the state to change precipitation to ice and rain and cut back some on accumulations. Even so, the Weather Service in Burlington wrote that “quick accumulation of snowfall will impact the morning commute, and may result in isolated to scattered power outages.”

After a multiday stretch of anomalous cold and wintry weather, high pressure will shift off the East Coast toward midweek. That will boost southerly winds and allow mild air to spread northward.

D.C. will be in the mid-70s on Friday before reaching 80 on Saturday and possibly the mid-80s Sunday. Friday will be in the upper 60s to near 70 in New York City, though the weekend could be cooler as a stalled frontal boundary lingers across the region.

The comparatively mild and near-seasonable temperatures will help eat away at whatever snowpack accumulates in the next 48 hours.