Weather

Bands Of Snow Along The Coast This Evening, Cold Continues

Evening Update
If you are a regular reader of this blog you know I was concerned about snow coming in off the ocean this evening. Unfortunately, for us snow weary inhabitants, snow bands are moving west/southwest off the ocean. These set-ups are very difficult to forecast. I expect this to continue to evolve, but move south with time. Parts of Cape Cod will hold onto the snow longest. These micro-events can drop 1-4 inches of snow, if they stay over an area long enough. Many of you won’t see more than a dusting and further west of the Route 495 might not see a flake. The area should exit Boston by 7PM. The south shore/parts of Cape Cod are most vulnerable for the highest amount of snow in this situation.

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Morning Blog
Yesterday I wrote about more snow for today. I mentioned if the storm moved further south, the snow would be less than predicted. The good news is this that’s what’s happening, so we are not going to see much if any snow from this system.

What you will notice today is light snow or even just flurries north of the Massachusetts Turnpike and a steadier snow the further south you are. I put a coating to 2 inches in a wide swath, but the two inches is most likely over Cape Cod. In that area there could be up to 3 or even 4 inches of fluff in some spots. There is a winter weather advisory posted on Cape Cod for snow. Boston sees up to an inch or so.

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The system will pull to the east this evening and take most of the snow with it. When I look at the computer models for the overnight hours and into Wednesday they keep trying to hold back a small piece of the storm along the coastline this evening. This hints at the chance of snow lingering or even becoming steady for a short time over places like Cape Ann or the New Hampshire coast.

These small scale events are virtually impossible to forecast correctly. I could take a position on what is going to happen either way and I might be right or wrong. However, it’s such a small area affected I just want to make you aware of its possibility.

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The image below shows a projected radar later this evening. The little blobs of blue are snowfall. These areas are what I’ll be watching for. The majority of you won’t even know it’s happening.

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Cold and Dry
Tomorrow, if there is snow along the north shore it will exit the area and we will see some sunshine mixed with clouds. Although highs will remain under 32F, where the sun does make an appearance, there will be some melting on the pavement.

Just Snow Showers
Thursday a weak system develops nearby and brings the chance for some snow showers. This won’t be a big system and the day could turn out just partly sunny with a few scattered snow showers.

You can find my updates to the forecast here and on Twitter @growingwisdom.


Cold Again
Friday is a very cold day once again, similar to yesterday, but not as much wind. The next storm threat comes after a dry and partly sunny Saturday.

Possibility Of More Snow
There is a chance for snow Sunday, but there’s also a chance we don’t get a storm. Unlike the past three weeks when I would tell you to move travel plans for Monday, I don’t feel that way right now. It’s not so clear to me that anything major will happen this weekend. Some models bring a moderate amount of snow, others nothing, so it’s just worth noting Saturday night and Sunday is the next chance of significant snow.

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Record Amount Of Cold
Today will mark the 15th day where the high temperature in Boston (and most other areas) has failed to reach 32F. If you look at the records for February you will find in 1885 there were 18 such days. So,if we see just 4 more of these below freezing days in the next 10, we break a very old record.

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How Long To Melt?
By some measurements we are in uncharted territory for the amount of snow on the ground. (modern times only) However, by looking back at some past data we can get an idea of when the snow will be gone, at least from the level.

We have a few things in our favor. The biggest is the sun is getting stronger each day. This time of the year the sun is similar to mid-October, while not July, the amount and strength of solar radiation increases each day.

Snow sublimates or disappears and dry fluffy snow does this even faster. Sublimation is when something changes phase directly from a solid to a gas. It’s not evaporation. It’s why the ice cubes in your freezer shrink after a few months. The snow always sublimates and settles. I estimate we’ve lost about 4-6 inches due to each of these processes since Sunday.

Using History To Predict The Future
Let’s assume it remains cold through March, not a bad assumption, right? If you look at March 1956, there was a big storm to start spring. Boston had 18 inches on the ground on the 20th.

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Even with a very cold 10 day period thereafter, 16 inches of snow disappeared. It’s very difficult to keep snow on the ground into April, while it can certainly snow in April and May, the sun on April 1st is similar to strength of the sun in the second week of September.

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