Friday December 20 2024 Forecast (7:31AM)

303 Comments

DAYS 1-5 (DECEMBER 20-24)

The coldest air mass of the season so far is on the way. Before it gets here, a minor winter weather event takes place today into tonight with an east to northeast air flow off the ocean around a storm system well offshore to our southeast, eventually tracking into the waters well to our east. This will help pull down cold air as we go through today. Ocean-effect precipitation is underway and will initially be in the form of either rain, sleet, or snow showers (rain showers most likely closer to the coast of the South Shore and Cape Cod), becoming snow showers for all with time. Additionally, expansion and development of the synoptic precipitation area will deliver some steadier snowfall mainly from the I-95 belt eastward, with lighter and somewhat more spotty snow extending further west. Out on Cape Cod, the warmer ocean water will impact the ability of snow to accumulate, so that reason there and the lighter precipitation amounts to the west will be the reason I’m going for under 1 inch of snow in those areas, with a general 1 to 3 inch snowfall elsewhere. The “higher” amounts of that range will occur where both ocean-effect and synoptic snow are maximized, and I cannot rule out a spot amount above 3 inches. This weekend will feature well below normal temperatures – the coldest air of the season so far. We welcome winter with the occurrence of the solstice at 4:20 a.m. Saturday, and that day will be quite breezy with the potential for scattered snow showers as an upper level disturbance moves through. Ocean enhancement of snow showers is possible over Cape Cod. The wind will slacken somewhat for Sunday and dry weather is expected except for the possibility of a few more ocean effect snow showers for the outer portion of Cape Cod. High pressure will provide “halcyon” weather for Monday – bright, dry, cold. A weak clipper low pressure system arrives via the Great Lakes Tuesday (Christmas Eve) with some light snow or snow showers possible. More about this potential in upcoming posts.

TODAY: Cloudy. Ocean-effect snow showers except snow, sleet, or rain showers at first MA South Shore to Cape Cod. Steadier light snow except rain or snow at first Cape Cod later in the day. Highs 30-37 except 35-42 Cape Cod, but a gradual temperature fall begins during the afternoon. Wind E to NE increasing to 5-15 MPH except 10-20 MPH Cape Cod.

TONIGHT: Cloudy. Snow likely, except rain/mix parts of Cape Cod. Snow accumulations 1 to 3 inches except under 1 inch west of I-495 and over Cape Cod. Lows 25-32 except slightly colder well north and west and slightly milder Cape Cod. Wind NE 10-20 MPH coast, 5-15 MPH inland.

SATURDAY: Variably cloudy. Snow showers likely. Temperatures slowly fall to 22-29. Wind N 10-20 MPH, higher gusts. Wind chill readings often under 20.

SATURDAY NIGHT: Partly cloudy. Additional snow showers possible Cape Cod. Lows 11-18. Wind N 5-15 MPH.

SUNDAY: Mostly sunny except partly cloudy with possible snow showers Outer Cape Cod. Highs Highs 22-29. Wind NW 5-15 MPH.

SUNDAY NIGHT: Mostly clear. Lows 10-17. Wind variable up to 10 MPH.

MONDAY: Mostly sunny. Highs 24-31. Wind variable up to 10 MPH.

MONDAY NIGHT: Clouding up. Lows 15-22. Wind variable under 10 MPH.

TUESDAY (CHRISTMAS EVE): Mostly cloudy. Chance of light snow or snow showers. Highs 27-34. Wind variable up to 10 MPH.

DAYS 6-10 (DECEMBER 25-29)

High pressure will become the dominant force in our weather holding off unsettled weather producing systems. Temperatures moderate to above normal, but not to any extreme.

DAYS 11-15 (DECEMBER 30– JANUARY 3)

Pacific-dominated air flow brings milder weather but minor precipitation threats as end 2024 and start 2025, but a stronger cold front may return Canadian cold to our region before the end of the period.

303 thoughts on “Friday December 20 2024 Forecast (7:31AM)”

  1. Thanks TK !

    A nice, consecutive 5 day stretch of winter weather.

    We really have gone through quite a winter-less stretch the last 2 years.

  3. Good morning and thank you TK
    Still snowing here. Ground has been dusted white.

    Unless I missed something, I don’t think I saw a forecast anywhere calling for snow starting by 7AM.

    We have a decent ENE wind right off of the ocean, thus the
    OE snows.

    Looks very festive! ME LIKE!

  11. Still snowing here, although the sky got a bit brighter.

    Synoptic precip is still down around Atlantic City, some 350 miles to our SW.

  14. Some sleet while walking the shore early this AM. Now it’s very light off and on flurries. Temp is 33F … might make it to 35 or 36 today.

      1. Yes you WxWacther did just that. And I take the NAM with a grain of salt at the moment.

        Does that discussion also apply to the 3KM version?

  17. IF the NAM ends up nailing this (like it has for many of our biggest snow events), I wouldn’t put it to bed just yet. OR find out what it is about it that makes it so good at these types of event and integrate that into another model suite.

  18. Been snowing for nearly 2 1/2 hours STEADY!
    No Stinken Snow Showers 🙂 🙂 🙂

    It looks like there will be a lull coming up fairly soon.
    We shall see. 🙂

    1. Technically those are snow showers. There’s just no separation between cells. Check radar loop.

      1. could have fooled me. 2 1/2 hours of steady snow is 2 1/2 hours of steady snow. Call it what you want. 🙂

  24. At car dealer in Norwood and looking at radar it’s coming down pretty good in JP. Snowing pretty good here too

  26. So, what is it going to be?

    FWIW, THE NAMS have this OE snow we’re experiencing
    in Eastern MA

    The HRRR didn’t even have it at all…..

    Food for thought????? Hmmmm

    Makes one wonder. 🙂

  27. If the NAM gets this would be wow. I remember a storm years ago that the NAM kept on showing insane numbers and it was dismissed. And we woke up to 2 feet.

  31. When I was awakened by the cats around 7am, it was lightly snowing here with everything covered. Now, it’s 35 with some drizzle and all the snow has melted.

  43. Sitting on the wrong side of the coastal front here.

    Light rain and 39F

    Oh and school just let out.

    Yahoo !!!!!!!!!!!!!!!!!!!!!!!

  44. Snowing again here!

    btw, did someone say that today’s set up could be interesting
    for ocean effect snow?

    Seems they did. 🙂

  47. Snowing lightly now here in Hartford.

    Not expecting much here in my area and not going to bite on the NAMS but if we could squeeze even an inch out of this one to whiten things up before the cold snap, I would be happy.

  48. Thanks, TK…

    With a break in the action, I want to wish my fellow educators, Tom, Julie, Dave and JPDave’s daughter (and anybody I’ve missed) a restful and well-deserved break! No more school wake-ups for 2024! Woo-Hoo!

    If you hear fireworks and the sound of tires peeling out of the parking lot in the direction of Middleborough, it will be me.

  58. Salem MA has dropped from 34 to 28F.

    Don’t know if it’s a brief SE movement of the coastal front or if it’s on the move for good.

  60. Down to 31.7 here and dropping slowly.
    Still snowing good. Streets are now snow covered and at least
    2 inches on grassy surfaces.

  61. Snowing harder now in downtown Hartford. Visibility is now way down. I can see some whitening of the rooftops and grassy areas but roads still just wet.

    2. Radar makes it look like it isnt even snowing here in Hartford and it is snowing to beat the band. Echoes look even more impressive back home in Coventry about 15 miles east of here.

      2. MEAUSREMENT as of 2:30 PM

        Just came in from clearing walks and car.
        Before I did that I took a measurement at 2:30

        3 inches on the nose and STILL SNOWING.

    1. Do we have anyone here from the Brockton area? I’m curious what conditions are like down there. Looks like some heavy snow at the moment.

  75. Feels like this will be an rain event along South Coast…just what we need…more rain. UGH! My sump pump is working overtime

  76. Flipping back and forth between rain/sleet/snow here in Quincy. More rain & sleet than snow. Oh well. I hope Boston is doing much better. 🙂

  78. Still mostly rain/some sleet. What is puzzling to me is that radar is “deep blue” all along the South Shore almost as far as Taunton.

    I don’t get it.

    Temperatures between 33-35 here in Quincy according to my iPhone.

  79. Days w/o 1” of snow for Boston:

    1. 386 days = 1937
    2. 352 days = 2007
    3. 343 days = 1926
    4. 342 days = 2012
    5. 339 days (and counting?) = 2024 ❄️

    I have given up counting the days of 4”+ as it’s 1000+ days. It’s probably going to be some kind of record anyway. Certainly not going to happen with THIS event.

  80. 0.7 Reading

    The places along the coast from Boston south that are having mix or rain, with temperatures above freezing, are basically screwed later when the temperature goes down and that freezes and ends up with a coating of snow on it.

    1. I’m thinking there was some melting and refreezing out here. I’m hearing reports of a fair amount of accidents.

  81. Thanks TK.

    For all the varying vibes, this storm is pretty much performing as expected it seems like. Mixing issues at the coast (for now), mostly dry/mood flakes outside 495, and a sweet spot in between. “Jackpot” should be somewhere just southwest of Boston… they’ll be some higher/lower numbers as always (makes it fun!) but just taking a consensus model blend from the past 12-24 hours would’ve done just fine.

    However, many models had completely given up on this storm days ago, and the mets here repeatedly advised that would not be correct…

  82. MEAUSREMENT as of 2:30 PM

    Just came in from clearing walks and car.
    Before I did that I took a measurement at 2:30

    3 inches on the nose and STILL SNOWING.

  83. NEVER a hint of rain here. MAX temp was 33 Now 30.
    SNOW the whole way with about an hour lull in the middle.

    1. Nam keeps the snow in here until 1Am or longer. Interesting.
      Personally, I think it QUITS long before then.

    1. Definitely not “passing flurries”. 😉

      I have a question though. Do you ever actually read my discussions? Or do you just come here to call everything a non event based on what’s happening in your backyard?

      The questions are serious. Please provide an answer when you can.

      2. I posted what is in my area as I’ve been doing all day . Yes I read it & yes I know it’s snowing in other areas , that’s good . I’m sorry but I’m never disrespectful here & sometimes folks don’t like my post , scroll by if you don’t like it . And for Arod to call me a troll( I’m Facebook friends with folks here Arod I’m no troll , so don’t ever call me that again please . Just remember folks this is a great blog , but we all have different opinions & likes regarding weather & if you don’t like something , just scroll by it . Arod I hope you still post but that comment was totally inappropriate!!

        2. My issue is you’re calling this a non event.

          Even if it’s for your area, this event hasn’t finished yet and I forecast up to an inch of snow along the coast down there and you will get that along with a flash freeze later. That is not a non event. Calling it that is disrespectful to me.

          In my blog, I carefully explained how the event was expected to unfold.

          1. Called it a non event at the time of the post Tk , has nothing to do with what your blog write up was . Let’s just move past it please . Now tonight will be an event as everything is going to become ice , I’m sure the salters will be out all night .

  89. My daughter will be driving from Halifax to Natick at 5 and I wondered if anyone could give me an update on any part of the drive. Lots of highways which I hope is a good thing. Thanks

    1. The traffic is brutal in many areas. Because it’s the first real event in many of those areas. And it’s friday afternoon, right before christmas, so it’s about As bad a combo, as you can get..

      Thankfully, it’s not a storm like december 9 2005…

      But still bad enough, if you are impacted by it.

      Sorry for the weird looking message.I was doing voice texting in a noisy place.

  91. Snow certainly brings out the passion in everyone.

    Deep breath now or there will be phone calls home to parents ……. Lunch detentions may follow.

    Gee, I’m on vacation too 🙂 🙂 🙂

    1. I’ll volunteer for detention 😉 I’m sure I’ve earned it more than once!

      Meanwhile. Happy happy vacation to you

  92. Logan briefly had the front pass back west of it and rose to 37F but now the wind backed again and it dropped.

    Even east of the front instead of being 37-40F, if has dropped to 34-37F.

    Not looking forward to the south shore’s ice up later but hoping to cover it up with snow.

  93. 0.5” so far at Logan.

    JPD I get the impression that the Boston neighborhoods are doing quite well. 🙂

    Still nothing here in Quincy. Just rain but at least now the latest radar verifies that rain/snow line. Immediate South Shore definitely missing out on snow for now.

  95. Watching live broadcasts from Boston as it’s snowing nicely. Maybe Boston (Logan) gets that first inch after all. 🙂

  96. Mostly rain with occasional mix here in at the StormHQ World Headquarters Compound. Took a drive up to South Shore Plaza earlier, went to all snow in Holbrook, was snowing in Braintree with the ground covered when I went into the mall. When I came out at 2:30, it was all rain again.

  98. I do observe on the radar those splotchy yellows representing ice pellets south of Boston are gone, replaced by the fuzzy echos.

    Out and about, wet snow is mixing in, so, the column above is cooling off more, evident with some low -mid 30s showing up even on cape cod and the islands.

    For southeast mass it’s really now down to the extreme shallow boundary layer.

  99. I was just Trying to get a few places. TOTAL GRIDLOCK.
    Once out, it took me 1/2 hour to go 1/2 mile and return home. roads are a MESS!!! No pizza tonight. Tomorrow. 🙂

    I saw several snow plows doing their thing, but roads remain snow covered and EXTREMELY slippery. I slid sideways for about 50 feet. Didn’t hit anything!!! Fun times.

    BE CAREFUL if you are out and about.

    And still snowing here, but it has lightened up.

  104. O.E.S. is still more potent than I thought it would be. Also, that little coastal front is heading ocean-ward shortly.

  105. From now (6PM) to storm’s end, my updated snowfall forecast is for another 1 to 3 inches mainly east of I-95, with the 2+ inch amounts focused from Plymouth County to Cape Cod. Additional snowfall west of I-95 will be mostly under 1 inch.

    Scattered snow showers tomorrow may add some minor additional accumulation anywhere in the region.

  106. FINALLY snowing here for real in Quincy. I believe it will continue to do so for the remainder of the event. 🙂 ❄️

    2. Quincy, Plymouth, down through Cape Cod, is just getting underway. As you saw, the snow portion of this event begins between 4PM and 8PM.

      The only change I made was to increase the snow amounts slightly from the South Shore to Cape Cod as that area will see a little better moisture while the cold air as in place. And out on the Cape additional ocean effect snow showers can persist through tomorrow.

  108. We have a dusting here in Pepperell, roads seem ok. Logan on the other hand must be a mess right now. Just saw a JetBlue flight peak through the clouds over us low and diverting to Manchester airport.

      1. Not yet, JetBlue starts early next year at MHT. You could be thinking of Breeze airways which has been there for about a year. Both have that Blue color. Looking forward to have JetBlue close to home.

  110. I was just looking ahead a bit. I do think the Tuesday event will be minor, however will produce snowfall accumulation. Details to come on Sunday’s update for that system. I can talk a bit more about it on tomorrow’s update too, which may be posted very late tonight as I won’t be around to write & post the blog tomorrow morning. I’ll be dipping my feet in the Atlantic Ocean and then going out to breakfast. 😛

  111. So much for the big “torch” on the long range models. The “warm up” after Christmas looks muted at best and doesnt look like it is going to have much staying power. Good news for the ski areas as they should get through it just fine.

    1. I can almost throw a stone to Brookline from my house
      and I am telling you we Had MORE that the reported 3.4inches at the time it was reported. 🙂

      I’ll take another measurement later, but I am estimating
      that we are at least at 5 inches total so far here. 🙂

        1. Lol.

          If we don’t end up getting any before the precip shuts off, I love taking the short December drives from snowless to decently/heavily snow covered.

          So, keep it all and enjoy every flake of it.

  117. Snowing like crazy here in Quincy with EVERYTHING nicely covered in white! All good for a White Christmas since temperatures will be well below normal between now and Christmas Day. After that it can get back up to 60 for the rest of 2024 for all I care. 🙂 ❄️❄️❄️

    1. Now that I am a newbie to Quincy I am going to have to be more patient with coastal fronts. Just because Boston has frozen precip doesn’t mean Quincy will automatically be included at the same time as well. It takes some time still to crash into the South Shore. This event certainly has now taught me that. 🙂

      I will say though that it was somewhat frustrating to watch Boston on tv news all snow covered and looking out my window still raining and sleeting. 😉

  118. That’s ok, what the ocean takes away in December, it can give back in late January and Feb.

    And as you’ll see in my new years predictions, I think a major blizzard is coming later this winter.

    1. Major Blizzard? Never heard of him. For what branch of the service did he serve? 🙂 🙂

      Hope you are correct!!

  119. Way more. I went back out 10 minutes ago and up to 5.9 so far. We must have been the jackpot zone. I’ll take a photo, remind the app we use for it.

      1. No,trust me it’s real!!! I’ve been out twice. Man the driving between 4 and 4;30 was Brutal and visibility was bad.
        It was REALLY coming down. The hardest I’ve seen it snow in years!!!

      2. lol definitely not. Much harder when it’s like two feet to find a good spot. This was straightforward. I have a board sheltered so I get a pretty legit number.

        1. JP must definitely have been the jackpot area. You looked like you were in a good convergence zone between the Ocean Effect and incoming synoptic snow. Your own private winter storm warning. Feels good to get that for once, huh?

          1. Indeed it does. I couldn’t believe it when it started snowing around 7 this morning. Except for about an hour lull where there were only a few flakes flying it has been snowing nearly 12 hours. In all ONLY about 1/2 inch per hour accumulations, but there were a few times it was snowing an inch an hour or more, then times of much less intensity,

  120. Arod and anyone else we are going to do a get together in January or February, send me an email if interested in joining. (Arod send me one either way, would love to chat) The more the merrier. Once we get a final number, I’ll send an email with location etc…

    hkasrawi@gmail.com

  121. My son just measured 2″ on our back deck in Coventry. More than I expected out this way. With a little additional accumulation on Christmas Eve, should hopefully ensure a white Christmas!

        1. If so, it would be “about” 10 miles as the crow flies.
          If this is not the area, make an adjustment and you’ll
          have a good idea.

          Use Google maps of your location. There is a miles scale
          and zoom out till you can see logan and check the miles
          as the crow flies. 🙂

  125. Still all rain down this way , it definitely is a lighter rain . Just took a ride to Kingston & salters are out

  129. https://www.ospo.noaa.gov/data/cb/ssta/daily/2024/ct5km_ssta_v3.1_global_20241219.png

    The post Christmas warmup now looks muted for at least a few days.

    We’ve had clipper to our north give us snow, this event, I guess it never got below 14F in Boston last winter and it might be 8F Sunday morning.

    La Niña in the central zones is quite healthy.

    I believe in a blizzard shot later this winter because I believe the polar jet will behave like it does in a La Niña and I’m hypothesizing one of those healthy clippers with an big 500 mb disturbance to drop out of central Canada and cut underneath us while explosively developing and then with blocking, there being a very slow motion around the benchmark. It’s nice to have La Niña back.

      1. La Niña is not really an automatic snow thing.

        Before last winter, we had three La Niña winters in a row. None of them were snowy in southeastern New England.

        Most of our snowy winters that are La Niña would be weak ENSO with other indices being in the right place. Neutral winters contain some of our bigger snow totals, and this winter, for all intense and purposes is going to be neutral to weak La Niña.

        That in itself is not enough to guarantee a lot of snow, because you still need other things to line up. They will line up once in a while, but not the entire winter. This was spotlighted in my winter outlook issued in November.

      2. Well, in theory, I think so.

        Lots of other factors.

        As you know down here where we are, we just don’t snow on marginal temp storms.

        We need really cold airmasses to our north to confront the ocean and they have been non existent the last 2 winters.

        In theory, I think La Niña tends to increase the chances much colder air will be nearby this winter.

        So, from that standpoint yes. Now, what the wild card is, is the moisture and storminess.

    2. I was actually about to comment on the temp outlook. The “warmup” is going to be a moderation from “well below normal” to “near to below normal”.

      While it looks warmer above us in terms of the upper pattern that does not translate to the surface. There’s going to be a lot of stubborn low level cold air just sitting around with nothing to dislodge it.

    1. Also, as has been mentioned, the mixed precip/slushy snow combined with now below freezing temps everywhere is a very ugly combination. Thankfully coming on a Friday night but still, very busy time of year for travel of course.

  133. Some signs for this were there.

    Could see on all models the inflow from the ocean at 850 and 925 mb.

    Perhaps the models under appreciated the convergence just west and northwest of the coastal front and that extra lift of the moisture advecting in at 850 and 925 mb did the trick. ????????

  134. So I told my son I measured 6.2 and he’s like dad no way. He’s like dad we have more so we want to measure in and around my board and he was correct it was 7.2.

  137. From Eric Fisher

    Storm total 4.4″ in Boston…snapping the record long 4″+ drought that had lasted 1,028 days

  139. Here in Hingham, we’ve had nothing but rain. We’d see big fat flakes but so far nothing has caught.

      1. Personally i think the universe knows how much I hate snow, so just sheer burning hatred alone has warmed the air aloft by a few degrees.

  142. NWS numbers, clearly they don’t line my 7.2. Dedham has 4.8 as of 4 PM so they must be close. I did not screw up the measurements.

    1. Nice not far apart. I did multiple measurements and sticking with it. Doubt the NWS will accept but I don’t lie. I’ll go out in the AM and take photo of ruler.

  144. 1. 4.7” total at Boston (Logan) to date. Not bad. 🙂 ❄️

    2. Boston’s w/o 1” snow streak ends at 338 days.❄️

    3. Boston likely to end its White Christmas drought since 2009. ❄️

    4. Boston got rid of a lot of snow “bugaboos” in one day! 🙂 ❄️

    1. It doesn’t count to technically because the one inch or greater of snow was not on the ground at 7am…. cheap out.

      It was a white christmas. 🙂

        1. I get the “definition” in terms of climate record, but it’s still silly for practical purposes.

          Most of the day was either snowing or had snow on the ground (the actual snowfall was only a few hours).

  146. Logan up to 5.2. Still haven’t seen mine post. I bet they waiting to see if anything pops up close to my number.

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