BOSTON (CBS) – I have a confession to make.
I took out my garden furniture on Sunday. Yes, I do. March 13th and I declared that winter (in my backyard) was over. So I’ll take full responsibility when that freak late-season blizzard hits later this month.
You should know that I didn’t go as far as putting away the snow shovels or emptying the gas from the snowplow. We’re going to need a few more weeks before we take the final step.
So I guess you could say I’m hedging my bets. I’ve lived in New England too long to bet everything on the end of winter in mid-March. But I will say that, given the current forecast, there is a good chance that we have seen the last significant snowfall. Sure, we could still see some snow flurries or minor snow accumulation in the coming weeks, but a plowing or impactful snow storm? The odds are against you.
First, some climatology to support my hypothesis.
Today, March 14, is the average date for the last inch of snow in Boston. Last year, the last inch came in mid-February. The year before it came in the middle of January! So just looking at recent years and averages, I’d say the odds favor no significant snow going forward in Boston.
Considering we know it won’t snow at all this week, I thought I’d look at how often it will snow in Boston after March 21, which is a week from now.)
An inch or more of snow has fallen in 7 of the past 20 years after March 21 in Boston. So you would say about 33% of the time. Once again, the odds are in our favor.
If you look at what’s happening in the atmosphere right now on a large scale, conditions are favorable for ridge formation in the eastern US (ie, heat) over the next 1-2 weeks. This is largely because some very important atmospheric drivers are “positive”:
- The EPO (Eastern Pacific Oscillation) forecast is positive, indicating low pressure in Alaska, pushing warm air from the Pacific toward the lower 48 states.
- The AO (Arctic Oscillation) forecast is positive, indicating that a strong low pressure (and cold) is being held in the Arctic and not released in our area.
- The NAO (North Atlantic Oscillation) forecast is positive, indicating a lack of “lock-on” near Greenland. A negative NAO is a great way to have cold and stormy weather this time of year. Do you remember the four Northeast Passovers in March 2018?
So given all this, the forecast for the next 1-2 weeks is for above average temperatures in the east.
Again, logically speaking, if we are going to be above average/warm for the next couple of weeks, the chances of significant snow are low. And that brings us to the end of March and into April. We all know that New England still CAN get snow this late in the season. But when it does occur, most of the time, it is not that significant and, thanks to a strong solar angle, it quickly disappears. Every once in a while, there’s a big one, like the April Fools’ storm in 1997, but those are the exceptions.
Also, the later in the season, the much more likely it is to snow in elevated areas than on the coastal plain. Last year, Worcester had what most would consider a major storm late in the season with 6.8 inches falling on April 16. Boston was only 0.1″.
So, the further north and west you live, and in particular the higher you live, the greater the chance that you MAY get some additional stacking before all is said and done. That brings me to one last interesting thing to watch in the next few weeks.
The city of Boston currently has 0.4″ MORE snow this season than Worcester. If Boston somehow held that lead for the rest of the season, this would be the first time in 48 years that Boston had beaten Worcester in full snow! That’s a crown the city of Worcester wouldn’t mind giving up.
There you go. With a few relatively warm weeks ahead, I say, why not enjoy yourself? Sunsets approach at 7 p.m.
Follow Terry on Twitter @TerryWBZ