By Terry Eliasen, Meteorologist, WBZ-TV Exec. Weather Producer

BOSTON (CBS) — Gas up the snowblowers, dig out the shovels, boots and winter gear…winter is about to get real! Are you ready? It’s been more than 270 days since our last battle with a significant snowstorm (March 4th to be exact), so we may all be a bit rusty. Not to mention it took us until January 20th to get our first inch of snow on the ground in Boston last winter, and that March 4th storm was the one and only real storm (producing more than 6 inches) of the entire season!ADVERTISING

Normally the first big one can be kinda fun, especially coming right around the holidays…but the timing of this one is going to make for some serious travel headaches. If you are currently planning on hitting the roads later on Sunday, I’d advise leaving grandma’s house a bit early…she’ll forgive you.

While it is still a bit early in the forecast process, all signs are currently pointing towards a major snowstorm for a large portion of our area. And, while there is time for track changes and adjustments, the sheer size, timing and duration of this impending storm clearly warrant an early heads up.

TIMING:

First Flakes: It starts snowing light to moderate between 2-5 p.m. on Sunday in southern New England. Should start as snow just about everywhere. I would plan on getting to your final destination by mid-afternoon Sunday…certainly by dark. The snow ramps up in intensity after dark and really comes down hard overnight Sunday night into Monday morning (this is the brunt or peak of the storm). I would estimate about 75 percent of the total snow will fall between 8 p.m. on Sunday and 8 a.m. on Monday. If the current forecasts hold, kids will all be receiving an extra day off on Monday, I highly doubt many schools and businesses in the “snow zone” will be open.

Between midnight and 7 a.m. Monday, there will likely be a change from snow to a mix and rain over southeastern Mass. The change starts first on Cape Cod and the Islands and then slowly pushes northward to just about Boston by dawn. This will keep snow amounts lower in these areas.

(WBZ-TV graphic)

During the day on Monday, the rain-snow line sits right around I-95, bringing mainly rain along the immediate coastline and over southeast Mass., and mainly snow inland (north and west of I-95). The precipitation will not be nearly as heavy as it was overnight, now coming in spurts and of a more showery nature. There will be some additional snow accumulation inland during the day on Monday, but it will be at a much slower rate, perhaps an inch every 2-3 hours.

Same idea for Monday night. Believe it or not, the storm is still going, not completely tapering off until sometime Tuesday morning…another day of no school?? Perhaps. The rain/snow line will collapse back southeast, changing the rain showers back to snow showers Monday night along the coast and over the Cape. An additional few inches of snow is possible across the area by Tuesday at dawn.

HOW MUCH:

Still a bit early for exact, zone by zone, forecast snow amounts but the potential is there for some areas to receive a foot or more from this storm.

Jackpot snow zones will likely be north and west of I-95, this includes much of Middlesex and Worcester counties and also inland Essex county. Southern New Hampshire will also be in the heavy snow zone. Again, there could be AT LEAST 6-12 inches in these areas and if all falls just right (or wrong depending on your point of view), some could see up to 18 inches of snowfall!

(WBZ-TV graphic)

The city of Boston and immediate North and South Shores will pile up the majority of their snowfall on Sunday afternoon and night, before changing and mixing with rain. So, somewhat lower amounts there, but still a sizable snowstorm (possibility of 6 inches or more).

Lowest snow amounts will be found over southeastern Mass., Cape Cod, and the Islands. They start as snow but inevitably change to rain by Monday morning. I would plan on 6 inches or less in these areas…with even lower amounts towards the outer Cape and Islands.

OTHER CONCERNS:

Thankfully, this storm arrives at a time of astronomically low tides. However, given the long duration of the event, there could still be some minor coastal flooding around the times of high tide…we will be watching the Coast between 2-4 a.m. and 2-4 p.m. on Monday.

Winds will be gusty along the Coast and Cape/Islands late Sunday night through early Tuesday morning. Expect east-northeast wind gusts 25-50 in these areas. By Tuesday morning, winds will shift to the north and eventually northwest and begin to gradually taper down.

Can’t stress enough the importance to stay tuned to forecast updates this weekend, especially if you plan on traveling Sunday. We have you covered on WBZ-TV, CBSBoston.com and CBSN Boston.

Follow Terry on Twitter @TerryWBZ

Click here for Westford snow storm data and past totals or select “Winter Snowfall“ under “Pages” on the left hand side.

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