If you’ve been following my forecast and style over the years, you know I don’t hype things, and while we won’t know for sure until this storm is over, it’s fair to say we are perhaps on the cusp of a historic snowstorm for some. Some of the snow accumulation we’ll see has the potential to be staggering. Whatever falls during Saturday won’t be very heavy at least, but it’s going to get blown around a lot. A wobble east or west could also move the bands of snow somewhat, so the projected amount of snowfall could still shift slightly.
The strong winds headed our way along the coastline have prompted a blizzard warning in some places, and winter storm warnings in others, together covering much of southern New England. Indications are that the storm will come close enough to the coast to produce heavy snow inland, but it’s east of Worcester the real jackpot is likely to occur. Within the heaviest area of predicted snow, bands can develop and produce over 2 feet, though these are usually localized and not all towns experience them.
How much snow?
When all is said and done, it won’t be surprising if some spots see 30 inches of snow within one of those heavy bands. In general, Greater Boston will see 16 to 24 inches.
The reason why the snow amounts may be record breaking is because of the cold during the storm. Typical snow to water ratios are 10:1. In this storm, they are going to be closer to 15:1 or 18:1. What that means is that the amount of moisture you need for a foot of snow could be 50 percent less than usual, leading to these high totals. The range of snow is based on the fact some of the heaviest bands could remain offshore and we would end closer to the lower end of the range.
The intensity of the snow Saturday will bring travel to a halt. Even plows are going to have trouble keeping up with the snow accumulation and may have to pull off the road during the heaviest bands to just wait it out.
Before sunrise Saturday a few inches of snow could already have fallen from the Mass Pike south and it will be getting heavier. The bulk of the snow will have fallen by 5 p.m. with some lighter snow the first half of the evening. At times, snowfall rates may exceed 2-4 inches per hour, and there could be some thunder and lightning along with those heavier bands. If you do have an emergency and need to be on the roads, be sure to take some food, a blanket, and a shovel just in case.
What about wind?
Winds are going to be strongest along the coastline, especially over Cape Cod and the Islands, where they could gust over 60 miles per hour at times, producing whiteout conditions as well as scattered power outages.
I think the power outages will be less likely as you go west of Route 128 because the wind won’t be as strong and the light nature of the snow will allow it to blow off the trees and wires.
Of note is the fact temperatures are going to drop all day Saturday. By evening, wind chills will be near or below zero and it will be hard to be outside and clearing snow without proper hats, gloves, and even a face mask. I think the cold Saturday afternoon is a big part of this storm.
There’s a high tide Saturday morning and another one Saturday evening. The one Saturday morning will take place just before the height of the storm, while the one Saturday evening will not be as big and will take place after the height of the storm. Nevertheless, there will be coastal flooding. The fast movement of the storm and the fact winds are going to be more northerly will prevent a major flooding event along the coastline. Notice in the chart below that the maximum forecasted tide surge is up to 13.1 feet, but that is only minor.
By sunrise Saturday, there will already be anywhere from 1 to 3 inches of snow on the ground, and it will be snowing steadily. In my opinion, if you don’t need to go out during the day Saturday, stay off the roads. It’s going to be nearly impossible to travel from mid-morning through the early evening. Because the storm is ending around midnight Saturday night, the roads should be cleared by midday Sunday, and you’ll be able to get out if necessary. This of course doesn’t include getting out of your driveway. Logan Airport has stopped flights for a period of time and the airport could officially close.
Final flakes and beyond
Most of the snow will be on the ground by 8 p.m. Saturday, but there will be some residual accumulation through about midnight. Sunday will bring back the sunshine, but remain cold. There will be a moderating trend by the middle of next week — however, that could be followed by more cold weather in the second week of February.
From a meteorological standpoint, what I’m most interested in is the rate of snowfall during this weekend’s storm. The Atlantic Ocean continues to be unusually warm and the heat energy from all that water is fueling this nor’easter.
Will we see some records?
Snowstorms and blizzards are nothing new to New England, but the intensity of this storm could be what we all remember. The largest amount of January snowfall in Boston was 24.6 inches, a record set in 2015, and the biggest snowfall of all time occurred on Presidents’ Day weekend in 2003 with 27.6 inches of snow.