Tuesday August 19 2025 Forecast (7:13AM)

73 Comments

DAYS 1-5 (AUGUST 19-23)

We’re in a northwesterly air flow which is part of a weather pattern that deflects Hurricane Erin away from the Northeast later this week, but also brings us some unsettled and very cool weather for a part of this forecast period – but not all of it! No big changes to yesterday’s overall discussion though. High pressure overhead now provides a chilly start to today. We started to see a lot of high clouds yesterday streaming down from the Great Lakes and Canada in that northwesterly air flow and that continues today. Eventually a more solid mid level cloud deck will overtake the sky tonight into Wednesday, when we can see some occasional light rainfall as well. At the surface, an onshore flow can add some low level moisture and patches of drizzle. After today’s “fair weather cool”, Wednesday will have that more cool and raw feeling to it, a little out of character for late August weather. Hurricane Erin’s impact on our region will be limited to heavy surf and large swells, more on south-facing shores than east-facing ones, but still somewhat significant upon the latter. Weatherwise, we will only see a shield of high clouds in the southeastern sky, maybe up to overhead for a while, during Thursday. The storm itself will remain well offshore as it passes by. Heaviest surf / largest swells occur Wednesday through Friday (peak Thursday), and will settle down as we head into Saturday. Erin’s circulation will expand as it passes by, and its interaction with high pressure to the north will create a healthy northeasterly breeze here on Thursday, into Friday when it gradually loses some punch and shifts more to the north. By Saturday, high pressure is in control with tranquil and warmer weather.

TODAY: Sun/cloud mix. Highs 71-78, coolest coast. Wind variable under 10 MPH with light coastal sea breezes developing.

TONIGHT: Mostly cloudy. Lows 56-63. Wind E up to 10 MPH.

WEDNESDAY: Cloudy. Occasional light rain, especially in the afternoon. Chance of drizzle. Highs 65-72. Wind E 5-15 MPH.

WEDNESDAY NIGHT: Mostly cloudy. Chance of showers. Lows 56-63. Wind NE 5-15 MPH.

THURSDAY: Mostly sunny to partly cloudy. Highs 72-79, coolest coast. Wind NE 5-15 MPH except 15-25 MPH with higher gusts coastal areas south of Boston, strongest gusts Cape Cod.

THURSDAY NIGHT: Mostly clear. Lows 55-62. Wind NE 5-15 MPH, higher gusts especially coast.

FRIDAY: Mostly sunny. Highs 75-82. Wind NE to N 5-15 MPH.

FRIDAY NIGHT: Mostly clear. Lows 56-63. Wind NW up to 10 MPH.

SATURDAY: Mostly sunny. Highs 78-85, a bit cooler at the coast. Wind variable up to 10 MPH with light coastal sea breezes.

DAYS 6-10 (AUGUST 24-28)

Warmer and a bit more humid August 24 ahead of an approaching cold front, which brings a chance of showers and thunderstorms later that day, and potential lingering showers and storms into a portion of August 25 as the front may be slow to pass through and exit offshore. Fair, cooler weather follows until the end of the period when there is another expected frontal boundary moving in with a shower and thunderstorm chance.

DAYS 11-15 (AUGUST 29 – SEPTEMBER 2)

Indications are for high pressure dominating into and potentially through the Labor Day Weekend (August 30 – September 1) with fair weather. May have to watch for a frontal passage and brief shower chance September 1 or 2, but timing and details of such features are not really certain this far in advance.

73 thoughts on “Tuesday August 19 2025 Forecast (7:13AM)”

  1. 34 years ago today was our most recent landfalling hurricane in New England. Bob – August 19 1991.

  2. I was talk about variability across relatively small regions on the previous post.

    Another couple of examples…

    Many lower elevation locations have had several 90 degree days in August. 1000-foot high Worcester airport has had zero. Their high for the month so far is 88, and it’s quite possible they will have no 90 degree days at all this month based on the upcoming pattern.

    Another great example! MVY airport, 42 this morning while some locations right at the shore were still near 60.

  3. Good morning and thank you TK.
    Low this morning 55 here.
    59 currently. Seems like sept or even october.

  6. Thanks TK !

    I enjoyed reading the conversation that followed my post about 90F days while potentially having a meteorological summer that was below average temps.

    I didn’t add into the conversation further because I fell asleep rather early which is good because I have a couple weeks to fall asleep much earlier than I have been since I’ll be getting up a lot earlier.

    2. Another great example of how weather is non linear.

      1983…

      30 days of 90+ at Boston.
      Hottest September on record.
      Not the hottest summer on record.

      1. Weather isn’t even linear within towns. Maybe we could move to temp maps similar to snow maps.

        1. Tbank you. I think you’ve been doing an excellent job. I just went through a spell of 5,6 and a miss thrown in.

    2. 3 also.

      2nd guess put first 2 letters in the right spot along with a 3rd letter in the wrong spot.

    2. Thank you both!

      We are celebrating in the Williamsburg, MA area. I can’t believe how lucky we got with the weather this week! 🙂

  10. A question for those with more knowledge than I have.

    Is the dew point an indicator of the low temperature we can expect say in the next 12-24 hours. For example, if the dew point is 48, should we expect the low temp for the day to be 48 (+/- 1 degree)? I guess another way to ask it is whether the dew point is a proxy for the low temp?

    1. It is an approximation to the lowest temperature given maximum cooling conditions. If we have a warm dry day in the summer
      with dew point 45, the low temperature will not reach 45, not even close.

      But on a clear calm cold night in the dead of Winter, with say
      the dew point at 8, then it could very well reach 8 or close to it.

      This is best left for TK or SAK to answer. The above were just my thoughts. Cheers

    2. It’s a good indicator of the potential lowest temp given….
      1) Perfect radiational cooling conditions.
      2) No changes from initial time to low temp occurrence.

    3. Caveat though is time frame.

      For instance, there can be a morning, say 10am where the DP is 48F, but by evening, it’s risen to 65F and there to stay, well …. then the low won’t be 48F

      Also, wind can keep the temp milder then the DP.

      But, in the big picture, your correct.

  11. Thanks TK
    Hopefully the weather tomorrow in South Williamsport, PA will be good for Fairfield CT taking on Nevada. Game is scheduled for 3pm. If Fairfield wins there in the U.S. Championship game on Saturday.

    1. Thank you for sharing times and days. Do I understand that if CT wins tomorrow, they’d play a second game later the same day

  12. If Fairfield wins tomorrow they will play Saturday for the U.S. Championship 3:30 on ABC. If Fairfield loses tomorrow they will have to play on Thursday and win that game to get to the U.S. Championship. On Sunday U.S. Winner will play the international winner at 3pm on ABC for the Little League World Series title.

    2. This is a favorite area of my son and DIL. We were there just four years ago for their wedding on greylock.

      Do you mind my asking the name of where you are staying. It looks like a place they’d love.

  17. I’m 100% certain now that August will come in below normal for temps across the extreme majority of if not all of southern New England, and I’m almost convinced now that the negative anomaly will be enough to overcome the modest positive anomaly of June & July combined so that the meteorological summer will come in at near to below normal for temps (for the 3 month period) across the majority of southern New England.

    There is absolutely zero sign of any sustained above normal temps now for at least the next 2 weeks which takes us beyond the end of August.

  18. Erin has made a sharper northward turn than NHC had forecast today. We’ll see if that holds. If it does, the impact may end up slightly less for NC … slightly less.

  19. The GFS (Great Fictional Storms) model took the 12z run off from hitting any US land areas with a major hurricane. I’m sure it’ll be back at it soon. 😉

    1. Thank you. Sending to my son. It’s such a special place to celebrate your wife’s birthday. And awesome weather to boot. I know you’ll enjoy every second.

    1. I have a dozen or more Humarock sweatshirts that I added to my August collection each year. I loved days like that at the beach

      1. I always have too. We had a good handful of those in our cottage years at Hampton when I was little. My father always had something fun planned for us on the “non beach days”. 🙂

        1. We did the same. Special memories!!

          My older brother was lifeguard at Hampton but that would more than likely have been before the time you had a cottage. I think it was roughly the late 1960s

              1. Thank you. That pony changed my daughter’s life and ours. Amazing critters ….all of our four and two legged family from the animal world

              2. I am laughing. Cab always had control. He was a pony after all. My daughter might have been 12; and if you look closely, she has a huge smile. No matter how strong he got, she knew he would take care of her

  24. Sox down 2 runs, load the bases with nobody out in the bottom of the 8th inning and then the 3-4-5 hitters in the lineup all strike out.

    Unless they mentally recover from that in the 9th, they’ll be hitting the road on a 3 game losing streak and they haven’t been great on the road.

    It was at home they were excelling.

      2. Bad loss.

        Your closer strikes out 3 in the top of the 10th without yielding a run and then with the ghost runner at 2nd and no outs, can’t get the run scored. Wow.

        1. I’ve been following the Sox from overseas. They’ve shown encouraging signs but also revealed longstanding issues.

          One thing to keep in mind is that the Orioles are not a terrible team. Far from it. I think it’s folly to think that the Red Sox would sweep them or really any team on their remaining schedule. It’s going to be a tough slog.

  25. A fairly typical late August day in Muswell Hill. Cloudy, some misty light rain around, 60F. It may get to 67F by mid-afternoon.

    My journey back to Boston begins at 4:45am on Friday as I make my way to Heathrow, which is at the other end of London.

    Man, I’m going to miss this place.

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