Blizzard Update: Historic Nor'easter Taking Shape
BOSTON (CBS) -- Here we go. An historic nor'easter is just hours away, you should complete any storm preparations immediately, this one is a lock.
Check: Weather Blog | Current Conditions | Share Photos
The storm is beginning to take shape and intensify off of the Carolina's at this hour with some initial snow bands already starting to spiral northward through New Jersey and Long Island.
Blizzard conditions are extremely likely for a good portion of eastern Massachusetts late tonight and into the day on Tuesday. This is not to be taken lightly. Driving will be near impossible at times with whiteout conditions, a potentially life threatening situation. I would advise avoiding travel if at all possible after 6 p.m. this evening. Schools will almost certainly close for at least Tuesday and perhaps Wednesday as well.
What is a blizzard? Just to refresh your memory, the official definition of a blizzard from the National Weather Service: Sustained winds or frequent gusts of 35 mph or greater and visibilities less than 1/4 mile for at least three consecutive hours.
This is the perfect setup for a long-duration wind and snow machine, something we only see once every five to 10 years. It will likely rival some of our biggest winter storms of the last 100-plus years and challenge the record books. In order to make it into the top 10 snowstorms of all time, Boston would need to receive more than 18.7". To be in the top five (along with storms like the Blizzard of 1978, the April Fool's Day Storm of 1997) we would need to get at least 25" of snow. I would say a top 10 event is nearly certain...and give about a 50-50 chance of reaching the top five.
The consistency of the snow will be very light and fluffy. Easier to push around and move, but impossible to measure with howling winds creating drifts 5-10 feet. The exception would be right along the immediate coastline and over Cape Cod where milder temperatures will make the snow much heavier, increasing the chances of widespread power outages.
Let's break down this storm hour by hour, day by day...
MONDAY
Noon-6 p.m.
Winds will begin to pick up out of the east-northeast causing some light ocean-effect flurries. During the afternoon some of the first bands of snow will try to push onshore over southeastern Massachusetts. By 6 p.m. there will be a coating to an inch or two south of the Mass Pike, not much if any accumulation north of the Pike.
6 p.m.-midnight
The storm begins. Steady snow overspreads all of Southern New England. Northeast winds steadily increase, gusting 25-50 mph along the coast by midnight. Snowfall rates of 1-3" per hour will become quite common over southeastern Massachusetts where some heavy banding sets up. By midnight there should be about 1-3" of snow on the ground north of the Mass Pike. South of the Pike total snowfall will range from 3-6". Roads conditions deteriorate very quickly.
TUESDAY
Midnight-6 a.m.
Blizzard arrives. The storm will begin to peak after midnight. Snowfall rates could range from 2-4" per hour with very heavy bands rotating northward. Sustained winds between 20-40 mph across all of Eastern Massachusetts with gusts 40-60 mph. Right at the coastline and particularly over Cape Cod and the Islands, wind gusts could exceed 60 mph, reaching near hurricane force (74 mph). Whiteout conditions will make driving, walking or generally existing outdoors impossible.
Everyone in southern New England will wake up to a tremendous amount of snow. 6-12" north of the Pike and 12-18" south of the Pike. Our first high tide of concern is around 4:30 a.m. Tuesday. Even though tides will not be astronomically high, the sheer force of the winds will pile up a lot of water along the coast. Astronomical high tide in Boston Tuesday morning is 10.5 feet. There could be a storm surge up to 3.5 feet, which would result in moderate coastal flooding with pockets of major flooding. Seas just offshore will build to between 20-25 feet!
6 a.m.-noon
The blizzard continues. The relentless snow and wind continue through Tuesday morning with pockets of whiteout conditions. Snowfall rates will vary with banding. In the heavy bands, up to 3-4" per hour is still likely. By noon on Tuesday expect 12-18" on the ground north of the Pike and 16-20" south of the Pike. Winds will continue to howl but start to veer to a more northerly direction. Gusts between 40-60 mph will still be common and up to 70 mph on Cape Cod. Needless to say travel will be near impossible on Tuesday morning.
Noon-6 p.m.
The storm rages on, the center of the storm will remain very close by, not too far from Nantucket. Snowfall rates will vary greatly as localized banding occurs. By 6 p.m. on Tuesday expect a widespread 14-24" of snow across the region. About 80 percent of the total snow accumulation will be done at this point. Winds will remain powerful but out of the north-northwest, mainly an offshore direction.
Astronomical high tide in Boston Tuesday evening will occur at 5 p.m. and be at 9.5 feet, a foot lower than the AM high tide. With winds also more offshore, I wouldn't expect the coastal flooding to be quite as severe as the prior tide. One location to watch would be in Cape Cod Bay. Winds there will be from the ocean and water will pile up and splash over vulnerable locations.
6 p.m.-midnight
Getting there. . . The shield of steady snow will be eroding into bands and snow showers. The snow will actually stop in some areas at times. Additional accumulations will be lighter, about 1-3" on average. Winds will remain very busy out of the northwest, gusting 20-40 mph with a few final peak gusts to 50 over Cape Ann and Cape Cod. Let the cleanup begin!
WEDNESDAY:
Midnight-6 a.m.
Digging out...The final bands of snow will rotate through, dropping our last inch or two of snow after Midnight. The storm will begin to finally lift north and east, away from New England. Winds stay gusty but not damaging. High tide at 530AM shouldn't be a major concern with winds now pushing offshore, just some pockets of minor flooding.
Final Snow Totals:
Cape Cod/Islands: 6-12" on the extreme outer Cape and Nantucket due to some mixing and low snow ratios. Snow totals increase dramatically traveling west down Route 6, up to near 2 feet at the canal.
Southeastern Massachusetts including South Shore, South Coast, Norfolk, Plymouth and Bristol Counties: Right now this appears to be the "jackpot" area. 20-30" are easily within range here. Perhaps up to 3 feet of snow in spots.
Boston area, nearby suburbs: 20-30", again, nearing a top five event all-time in Boston if we reach 2 feet.
North and West of Boston including I-495 area from Lawrence to Marlboro and out to Worcester, most of Essex, Middlesex and Worcester Counties and Southern New Hampshire: 18-28"
Farther north and west including Western MA, Southern VT and Central New England: A bit farther away from the storm and the heavy banding, so slightly less snow totals. . . 12-18"
Northern Ski Areas: Not the jackpot region but they will take it. Easily a foot of fluff up there perhaps up to 16 or 18" in spots.
So there you have it...goes without saying but please stay tuned to updated forecasts over the next 24 to 48 hours. This is one of those storms that you really do not want to mess with or take any chances on the roads or outdoors in general. Stick with WBZ on air and online for frequent updates.
Follow Terry on Twitter @TerryWBZ
