UPDATE: Bolaris’ Weather Watch: Major to severe snowstorm looms

The latest computer models continue to maintain a very secondary intense storm to form along the Carolina coastal sections by Friday evening. The one significant change is a more easterly trend, which would allow for a colder solution for the Northeast. Right now it looks like it will be all snow from D.c. to Boston. The other change is slightly quicker. Even through the liquid equivalent amounts were slightly reduced the snow total potential remains high.

Thebulls-eye has been consistent of late with the D.C.-Baltimore region in the cross hairs for perhaps the biggest snow amounts, 18 to 24 inches is certainly a strong possibility. Blizzard watches have been posted for D.C. metro area, with Winter storm watches expanding northward into the Northeast.

This will be a very intense storm of long duration with blizzard conditions spreading into Philadelphia and NYC on Saturday. It still remains to be seen how far north the extent of high impact weather makes it into the Boston region. Right now computer models still suggesting around a foot, but that might be generous if this easterly trend continues.

Major tidal flooding for everyone.

This is what we do know as of 1p.m. Wednesday (this will be refined andadjusted as we get closer to crunch time).

The set-up:

By Friday morning a rapidly intensifying storm will be taking shape somewhere along the North Carolina coastline. An arctic high will be funneling down cold air into the system at the same time the Gulf Stream helps to fuel the storm, with a rapidly expanding heavy snow, sleet and rain shield moving north.

Snow will arrive in the D.C region during the afternoon on Friday.

Snow will arrive in Philadelphia by the evening commute (between 5 and7 p.m.)

Snow will arrive in NYC between 9p.m. and midnight.

Snow will arrive in Boston by daybreak Saturday.

The best chances of mixing with rain and sleet will be from the I-95 corridor and points east.

If the storm reaches its full potential, 1 to2 feet of snow could fall along or just west of the I-95 corridor from DC to Philly to NYC. Boston should remain all snow.

The best chances of 12+ will be from just west of Philly to just northwest of NYC, and D.C.

Coastal sections, especially the New Jersey and Delaware coastline, will experience major tidal flooding, major beach erosion, and winds that will gust to storm force 50mph+ (storm force=39mph).

Coastal sections will experience heavy wet snow changing to wind driven rain, and then back to snow before generally ending Sunday later in the day and at night further north.

The storm will be of unusually long duration of at least 48hours of high impact weather.

Blizzard conditions likely for the Northeast corridor. Visibilities will drop to white-out conditions.

The major cities along the I-95 corridor (except Boston)should see at least some mixing of rain and sleet and possibly a changeover to all rain for a time, before changing back to snow. This will cause considerable differences in the heavy snow amounts.

Power outages will be common.

Tree limbs will snap.

More updates and fine tuning of the storm’s impact will be made as new guidance comes in.

I would strongly suggest be where you want to be no later than 5 p.m .Friday as travel will eventually get shut down if this pending nor’easter reaches it’s full potential.

Potential impact Philadelphia:

12+ inches especially just west of the I95 corridor.

1-2feetpossible across parts of Chester, Montgomery, and Bucks Counties.

Mixing with sleet and rain, possible changing to rain for awhile from I-95 and points east.

Any mix will change back to snow during the day or by evening on Saturday.

All snow likely for Saturday night through Sunday morning.

Major tidal flooding, beach erosion for all shore locations.

Storm force winds coast gusts to 50+mph

Power outages will take place

Storm arrives late Friday, moves away by late Sunday

Potential impact New York:

Snow arrives between 9p.m. and12 p.m. Friday night.

Saturday: Heavy snow andwind, 12+ inches possible by the time it ends Sunday evening.

Possible mixing of sleet and rain (even a change over to rain can’t be ruled out before changing back to snow).

Snow amounts dependent on mixing.

All snow northwest of city.

Eastern Long Island: Heavy snow to sleet, possibly to all rain, then back to snow. 12+ inches still possible even with mixing, as prolonged backlash likely.

Moderate to major tidal flooding

High tidal surges along beaches on the north and south shores

Power outages.

Storm pulls away after 5 p.m. Sunday

Boston/Southern New England Impact:

Currently still the toughest call to make as models diverge on the northern extent of precipitation and thus impact and snow amounts.

My thinking is Providence and the Capes will take a major hit from this as the nor’easter will track more east-northeast as it moves southeast of Montauk.

This should put the Capes/Providence in the more intense northwest quadrant banding of snow, not allowing for mixing with 12+ inches likely.

Boston and the hills to the north and west could see a sharp cut-off of the heavy snow line.

How much snow for Boston is still very much uncertain.

Major tidal flooding and beach erosion.

Power outages, especially along the coast.

Wind gust Storm force 50+ mph

Snow should arrive by daybreak Saturday.

Moves out late Sunday night. Could linger at the Capes until Monday morning