Wednesday December 17 2025 Forecast (7:30AM)

62 Comments

DAYS 1-5 (DECEMBER 17-21)

High pressure sits to the south today with a low pressure trough approaching from the west. The moisture-starved trough will do nothing but help the breeze stay active and gusty today into tonight, and shift the wind a bit before the high pressure area noses in and diminishes the wind on Thursday, which will continue a trend to less chilly air. A stronger, larger low pressure area cutting through the Great Lakes Thursday night into Friday, then heading down the St. Lawrence Valley later Friday, will produce a stronger southerly wind, and with the help of a sharp cold front moving into the region, a solid band of rainfall, which will largely wipe out any snow and ice on the ground. As the front moves through, the rain shuts off, the wind shifts to west, and we see a return of dry, colder air Friday night through Saturday, though not as cold as the recent cold air mass we experienced. A weaker low will be passing north of our region on Sunday, and its warm front / cold front combo can produce brief precipitation around here, mainly northern areas, but this should be minor at best. Mainly noticed will be the mix of sun and clouds and breezy weather for Sunday. The winter solstice occurs on Sunday at 10:03 a.m. EST.

TODAY: Sunshine and high clouds. Highs 37-44. Wind SW 5-15 MPH with higher gusts.

TONIGHT: Partly cloudy. Lows 24-31. Wind SW 5-15 MPH shifting to NW with higher gusts.

THURSDAY: Sun much of the time then more clouds late. Highs 44-51. Wind variable to S up to 10 MPH.

THURSDAY NIGHT: Clouds thicken. Widespread rain showers arrive west to east overnight. Lows 37-44 evening, rising through 40s overnight. Wind S increasing to 10-20 MPH with higher gusts.

FRIDAY: Overcast with widespread rain showers including the slight chance of thunder during the morning. Showers end west to east with a sun / cloud mix developing during the afternoon. Highs 55-62 in the morning, falling through the 50s into the 40s from west to east during the afternoon. Wind S 10-20 MPH except 20-30 MPH South Coast, gusts as high as 45-55 MPH, strongest coastal areas and higher elevations, shifting to W from west to east midday on.

FRIDAY NIGHT: Partly cloudy. A passing snow shower possible. Lows 22-29. Wind W 10-20 MPH, gusts 25-35 MPH.

SATURDAY: Sun followed by clouds. Highs 35-42. Wind variable up to 10 MPH.

SATURDAY NIGHT: Variably cloudy. A brief period of very light snow possible mainly north of I-90. Lows 22-29. Wind SW 5-15 MPH,.

SUNDAY: Partly sunny. A late-day snow shower possible. Highs 38-45. Wind W 10-20 MPH.

DAYS 6-10 (DECEMBER 22-26)

Clipper low pattern and up-and-down temps, tending to be colder vs. milder. Watching for minor snow or snow shower events, timing uncertain from December 23 on.

DAYS 11-15 (DECEMBER 27-31)

We head down the home stretch of December and 2025 with a similar pattern continuing – up and down temps and the chance of one or two mainly minor precipitation events, timing and details TBD.

62 thoughts on “Wednesday December 17 2025 Forecast (7:30AM)”

    1. Yikes. 2 is superb. We don’t see a lot of 2s.

      I’m in the caboose with 5. 3 and 4 were words that fit but had wrong first letter.

      Reply

      1. Thank you. You got it, so that is good.

        I tried a new starting word and picked up 1 letter in position and one letter out of position. So I started trying words in my head and was having trouble getting any to fit. Then it just came to me. Try this word and I figured perhaps I’d catch another letter or 2, BUT it WAS the WORD.

        I have played 178 games and only got it 2 guesses 4 times.

        Reply

          1. Thank you. Crazy game.
            Sometimes we’re all over it and sometimes we are totally lost.

            There are many here that are totally on it more often than not.

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  16. Thanks, TK!

    The Wayback Machine today stops at December 18, 2023, two years ago tomorrow, when a period of strong winds (60+ mph) and heavy rain blew through the area.

    Much of Middleborough lost power that morning. We had an unexpected dismissal during lunch period.

    Vicki posted this radar image on 12-18-23 around noon as the most intense weather crossed the region:

    https://imgur.com/a/Hx7A7b8

    I wonder if we will have a similar set-up this Thursday night and Friday. A High Wind Watch has already been hoisted for the Cape and the Islands.

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  17. Yesterday felt MUCH warmer during my run than today. Despite the colder temperature, sun yesterday felt warm, frankly. Today’s lack of sun makes a big difference.

    I don’t know the physics of it or biology, but I do believe that for long distance running the sun may be more of a determinant of body adjustment than the outside temperature: In both good ways and bad. In summer, the sun is my enemy on a long run. I hate it. In winter, on the other hand, the sun is my friend. I like it.

    Reply

    1. I coached track and cross country. Long-distance runners are the most dedicated athletes to their sport. No matter the weather, they put in the roadwork.

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  18. I wonder if they’ll change the song to “I’m dreaming of a Clipper White Christmas just like the ones ….”

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  19. CF, I’m afraid my dedication to running is a bit of an addiction. Obviously, it’s a better addiction than, say, heroin. But still. If I don’t run a certain amount every day I almost panic. That is NOT normal. It has become somewhat of an obsessive-compulsive disorder, sort of like Nomar adjusting his gloves at the plate (I bet if you forbad him from doing that, he would have panicked).

    One thing the running does in a very beneficial way is it has me experiencing urban nature in all kinds of weather and in all seasons. The animals I see during my run are almost like friends. I see them scurrying about (squirrels and rabbits) or waddling (geese and ducks) or flying (all kinds of birds) or wading (heron) or swimming (muskrat and different kinds of fish) or sunbathing (turtles). Some are seasonal companions, like the red-winged blackbirds or turtles and rabbits for that matter (I believe they hibernate during winter). Others accompany me on my run year-round, in heat and humidity, crisp fall days, cold wintry mornings, rainy days in spring.

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  20. Thanks TK.

    12z models (GFS, Euro and CMC) continue to be pretty consistent showing a clipper system passing through the area later on 12/23 into early 12/24 with a period of light snow or snow showers. Doesnt look like a big deal but it might be enough to whiten the ground in at least some areas for Christmas Eve and Christmas Day. Despite this Friday system which will wipe out the snowcover in many areas, I would not say our chances for a white Christmas are zero.

    Reply

  21. Thanks TK.

    I don’t think I’ve ever seen such a strong, classic, and persistent -PNA as the pattern we’re into and going deeper into over the next couple of weeks. Pick any model/ensemble at 500mb and watch the way the Aleutian Islands ridge is constantly rebuilding and forcing a downstream trough into the Gulf of Alaska. That then floods the CONUS with Pacific air. West Coast gets absolutely annihilated with rain, snow, and tons of wind (check the NWS national hazards map for today!)

    This pattern and its ensuing downstream effects will take at least several weeks to break. It’s an exceptionally warm look for most of the Lower 48. Record warmth incoming for many. Not nearly as much of a slam dunk for New England, clippers and cold air damming still matter! But it will likely prevent any “classic” coastal storm type patterns for quite a long time to come, and likely keep SNE snowfall potential below normal well into January at least. If it sticks around, a -PNA becomes a little less hostile for SNE snow as winter goes on, temperatures become climatologically colder and the barrage of Pacific energy can open the door for overrunning or occasionally “Miller B” type events. But you’d still rather see it flip if you’re looking for big snow chances. We’ll see what happens but for now that is definitely the “teleconnection to watch.”

    Reply

    1. Thank you WxWatcher. So much for the December to remember. I wonder how much of the Temperature anomaly will be wiped out by month’s end?

      All this internet hype about the Polar vortex with cold and snow. Ha! Yes, the 1st 1/2 of December was well below average temperature-wise for sure. But I have not been impressed and as for snow, well that’s a joke in itself.

      Well now we’ll have to wait and see what happens.
      Can we get some cold to slip down and a clipper redevelop South of us for a moderate event. (Hey I have seen heavy snow events with that set up, just not very often at all).

      Time will tell but color me snow starved….

      Reply

      1. I guess that blows my snowfall prediction of 56.2” for Boston. I thought Boston might double last year’s total (28.1”). Should’ve known better.

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        2. Ummm, you might want to wait not only until winter begins, but actually takes place, and into spring, before you try to verify your snow forecast.

          This is December 17.

          This once again is the SAME though process that I talk about not using year after year after year after year after year after year after year ……. after year.

          You cannot verify something before it occurs.

          Reply

  22. After an exceptionally mild December thus far throughout Europe, the weather gods are about to flip the switch. And now, there are indications that places that very mild for weeks on end, such as the European part of Russia, are about to do a 180. Record cold could in store in parts of Eastern Europe. Western Europe won’t escape the cold, though it will be modified. This pattern has a tendency to be longlasting, as a stationary area of high pressure expands and strenghtens by the last week of December. Its positioning is a bit west of a usual Scandinavian high. I do NOT think this bodes well for us in terms of persistent cold or snow.

    Reply

    1. The Northeast will be partially excepted from the milder pattern as indicated by WxWatcher about, with the -PNA. We’ll have a lot of clipper type systems bringing in cold shots, but I don’t think we’ll be persistently below normal in temp like we were for the first half of this month. We’ll just be near to slightly below normal while much of the country is above normal.

      I also agree with the lack of classic coastal storms. If we snow here, it’s a twist in the existing pattern where a clipper is allowed to slow down and intensify with a deeper, slower trough.

      The first 2 surprises of winter (in terms of my forecast expectations) are the degree of IOD going negative and the negative PNA being as prominent as it is. Ironically, my expectation was for both of those indices to be mainly neutral at this point.

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      1. Relying on clippers around here is like relying on a white Christmas every year. They usually go north of us or don’t develop south of us in time. We might as well rely on a Bermuda High. 😉

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        1. Well, the Boston area doesn’t get a white Christmas every year. They never have. And the Bermuda High won’t be a factor for a really long time. 😉

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  23. Eric mentioned something interesting on air that I didn’t know:

    “Cold air blows persistent but warm air blows in bursts.”

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    1. I’m not exactly sure what he means by that, but if he means what I think he does, he’s only 50% correct.

      I didn’t see it, so I can’t fully be sure, but warm air blowing in bursts indicate the idea of a strong low level jet (strong winds just above the surface) that are brought down in bursts by convective activity. However, this wouldn’t quite be the case without the convective activity, and a strong gradient can most certainly produce more persistent wind with warmth.

      Same with cold, you can have persistence with gradient, or you can have bursts with sun-heated air which creates a kind of rolling effect to the overall air.

      Reply

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