Friday August 11 2023 Forecast (7:32AM)

88 Comments

DAYS 1-5 (AUGUST 11-15)

Canadian air behind departing low pressure brings a nice summer day today. We will have a gusty breeze from mid morning well into the afternoon, and expect some diurnal cloud development when the sun heats rain-moistened ground with cooler air above. The wind settles tonight and any clouds dissipate and we’ll have a comfortable night by August standards. If you’re up late and are a star gazer, late tonight (early Saturday morning post midnight / pre dawn) will offer a decent opportunity to view the just-about-peak Perseid meteor shower. Best way to view it is away from light sources as much as possible, outside for a while to let eyes adjust, and looking high in the north and northeast sky for thin-appearing, fast-moving streaks. Saturday will dawn with sun which will be dominant for a good part of the day before some clouds arrive later. This will be in response to upstream showers and thunderstorms with a pre-frontal trough approaching from the west. This trough will trigger showers and thunderstorms into western New England by late-day and early evening, and the remains of those can then move across the WHW forecast area from west to east in broken to scattered form mainly after sunset Saturday. Lingering clouds from these may hinder viewing of the peak hours of the Perseid meteors in the early morning hours of Sunday, but with a little luck some partial clearing can take place to allow for at least some limited viewing. A cold front will have to cross the region before the shower and thunderstorm threat is eliminated, and this will take probably until late morning (west) and early afternoon (east), so those will still be in the forecast as a hit-and-miss occurrence for Sunday’s morning and midday hours. Even post front, it will stay on the humid side later Sunday, with slight drying into Monday as a little bubble of high pressure moves close to the region. The zonal flow pattern we’re in sends the next disturbance our way for Tuesday. Low pressure will be set to track north of the region late Tuesday, but before it gets here a warm front will push into and through the region, followed by its cold front as the low moves by. Details to work out will be frontal timing, how long we’re in a warm sector, and resultant shower and thunderstorm intensity and coverage. But it being day 5, it’s too soon for that, so just paint Tuesday as an unsettled day with details to come.

TODAY: Sun and passing clouds. Highs 78-85. Dew point near 60. Wind W 5-15 MPH, higher gusts possible.

TONIGHT: Mostly clear. Patchy ground fog. Lows 60-67. Dew point near 60. Wind SW under 10 MPH.

SATURDAY: Mostly sunny to partly cloudy. Late-day shower or thunderstorm possible southwestern NH / central MA / eastern CT. Highs 80-87. Dew point 60+. Wind SW 5-15 MPH.

SATURDAY NIGHT: Variably cloudy. A shower or thunderstorm possible. Patchy fog. Lows 62-69. Dew point near 60. Wind SW 5-15 MPH.

SUNDAY: Partly sunny. Chance of a shower or thunderstorm morning and midday, diminishing from west to east. Highs 78-85. Dew point 60+. Wind W 5-15 MPH.

SUNDAY NIGHT: Mostly clear. Lows 57-64. Dew point under 55. Wind W up to 10 MPH.

MONDAY: Sun then some clouds. Highs 77-84. Dew point rising back to near 60. Wind variable to S up to 10 MPH.

MONDAY NIGHT: Variably to mostly cloudy. Lows 61-68. Dew point near 60. Wind SE under 10 MPH.

TUESDAY: Mostly cloudy. Chance of showers and thunderstorms. Highs 72-79. Dew point 65+. Wind S 5-15 MPH.

DAYS 6-10 (AUGUST 16-20)

A generally zonal flow pattern is expected, disturbances passing by with a couple shower and thunderstorm chances – most likely August 17 & 19. Temperatures near to slightly above normal.

DAYS 11-15 (AUGUST 21-25)

A weaker westerly flow with near to below normal precipitation and near to above normal temperature expected heading into late August.

88 thoughts on “Friday August 11 2023 Forecast (7:32AM)”

  2. Thanks TK.

    Still sticky this morning in eastern sections from ME to NYC. Interesting how humidity still around BEHIND the cold front but dry air never lingers behind a WARM front. Heaven forbid! 😉

  3. Patriots QBs for 2023:

    1. Mac Jones
    2. Malik Cunningham
    3. Bailey Zappe

    I would say that Cunningham is the new Zappe!

  6. Athough the Norton NWS office is not too robust on
    Tomorrow’s severe potential, they do seem rather
    concerned about the potential for Tuesday.

    Unsettled weather returns late Monday into Tuesday as another short-
    wave disturbance aloft advances from the Midwest. 00Z suite of model
    guidance paints this as a rather robust feature with the potential
    to develop a sub-1000 hPa surface low. Depending on what time the
    strongest forcing arrives in southern New England, a severe weather
    threat could be on the table for Tuesday. Model guidance is showing
    the potential for a robust low-level jet near 30 knots at 925 hPa.
    Furthermore, some deterministic model guidance is suggesting 50 to
    60 knots of 0-6km shear. Rich moisture will be in place as well with
    PWATs well over 2 inches. The only question is how much instability
    will be available in the atmosphere as the associated surface
    frontal wave tracks over the region. If the passage occurs during
    peak heating on Tuesday afternoon, we`ll certainly have to be on the
    lookout for severe thunderstorm potential. CIPS severe weather
    probability guidance is currently suggesting a 15 to 30 percent
    chance of severe weather across a large portion of the east CONUS.
    CSU machine learning probabilities are suggesting this potential as
    well.

  9. TK, I appreciate the direction for the persieds. I always associate them with Mac’s birthday…also SClarke’s wife’s birthday and the anniversary of hurricane Bob. I’ve yet to see a meteor when watching them though. Perhaps this year!

  10. Thanks TK
    Will see what the SPC updated outlook says when it comes out around 130 this afternoon.

      1. Vicki I ended up watching the game last night. It was an entertaining game. Good luck to Gray Maine next week at the Little League World Series.

    1. WOW!! That is outstanding. THANK YOU VERY MUCH!
      Most informative!!!
      I REALLY learned something from that post.

      many thanks again.

    4. Agree with others. I had read it last night but wanted to give it a second read. Glad you reposted as I forgot to go back. Also saved

  12. Quick peak at the latest SREF for tomorrow night into Sunday morning most of SNE with the exception of eastern MA in the low tornado risk between.

  13. Post mortem on yesterdays event and when, I think, the short range models have their most accurate simulations.

    3km NAM: I chose its 18z run yesterday. It got the Merrimack valley and northern Essex county rains and came close to the south coast rains.

    https://www.pivotalweather.com/model.php?m=nam4km&p=qpf_acc-imp&rh=2023081018&fh=12&r=us_ne&dpdt=&mc=

    I can’t find a NAM run that ever got it, in my opinion. There were ones yesterday that had the gap btwn rain areas, but the rain areas weren’t in the locations that received rain.

    Yesterday’s 12z RRFS A sniffed out the Merrimack valley and northern Essex co rain but certainly missed out on the Long Island, block island and Martha’s Vineyard tstorm/rain

    https://www.pivotalweather.com/model.php?m=rrfs_a&p=qpf_acc-imp&rh=2023081012&fh=24&r=us_ne&dpdt=&mc=

    HRRR: yesterday’s 12z HRRR did pretty well with a hint of the northern mass rain and and a decent signal on Long Island, block island and the vineyard.

    https://www.pivotalweather.com/model.php?m=hrrr&p=qpf_acc-imp&rh=2023081012&fh=24&r=us_ne&dpdt=&mc=

  16. The NAM has gone bonkers.

    Here is the Significant Tornado Parameter for 15Z Sunday

    https://www.pivotalweather.com/model.php?m=nam&p=stp&rh=2023081112&fh=51&r=us_ne&dpdt=&mc=

    And 18Z

    https://www.pivotalweather.com/model.php?m=nam&p=stp&rh=2023081112&fh=54&r=us_ne&dpdt=&mc=

    Here is a sounding for the highest parameter at 15Z

    https://ibb.co/Dwc17cm

    Before anyone gets alarmed, these sounding threats on Pivotal Weather tend to be OVER COOKED most of the time.

    But this sounding has the threats as PDS !!!
    OR
    Particulary Dangerous Situation.

    Not sure I have ever seen that in SNE.

    Interesting….

    2. 12Z 3KM NAM Significant Torndao Parameter
      15Z or 11AM Sunday to 19Z or 3PM Sunday

      https://www.pivotalweather.com/model.php?m=nam4km&p=stp&rh=2023081112&fh=51&r=us_ne&dpdt=&mc=

      https://www.pivotalweather.com/model.php?m=nam4km&p=stp&rh=2023081112&fh=52&r=us_ne&dpdt=&mc=

      https://www.pivotalweather.com/model.php?m=nam4km&p=stp&rh=2023081112&fh=53&r=us_ne&dpdt=&mc=

      https://www.pivotalweather.com/model.php?m=nam4km&p=stp&rh=2023081112&fh=54&r=us_ne&dpdt=&mc=

      https://www.pivotalweather.com/model.php?m=nam4km&p=stp&rh=2023081112&fh=55&r=us_ne&dpdt=&mc=

  17. 36 hrs or 12z Wednesday’s short range model simulations of last night’s event get an F

    Dreadful simulations. Not even close.

    I know that doesn’t hold true for all events.

    But we’re about 36 hrs out on the next one, so …….. 🙂 🙂 🙂

    1. Yes, that is a reasonable assessment.

      HOWEVER, I see too many models beginning to line up
      for Sunday.

      SREF, WRF ,HRRR, NAM, 3KM NAM

      Not saying anything will happen, but this is enough for me
      to take notice.

      I wonder if the next Norton NWS discussion picks up on any of these? The last discussion was kind of ho-hum for Sat night/Sun Am and more concerned with Tuesday.

      No matter, interesting times ahead.

      I can’t ever remember a time in SNE where there were so
      many tornado threats!!!!!

      1. Agreed.

        The jet stream is so far displaced to the south, strong dynamics over oppressive humidity supplied by the cooked oceans.

        Until this jet stream moves north, the country as a whole is going to be well above average for severe weather. It’s nuts !!

        1. Indeed.

          for a “drier” day, the dew point is still 63 here.

          Let me calculate that to check

          Calculated it is 61

  19. https://www.weather.gov/wwamap/png/mfr.png

    Excessive heat watch for Sunday/Monday in Pacific Northwest somewhat indirectly tied in to early next week’s system.

    The excessive heat watch results from a ridge developing in the Pacific Northwest and thats then going to lead to a very strong disturbance dipping into the Great Lakes.

  20. https://www.star.nesdis.noaa.gov/GOES/sector_band.php?sat=G18&sector=ak&band=10&length=24

    I don’t feel confident on this but I tried to go out to about 108 hrs on the 00z euro and then slowly back it up to present time at 500 mb.

    I feel like the disturbance for late Monday/Tuesday might currently be in far south west Alaska, rotating around the common Aleutian Islands upper low.

    It’s going to head northeast then up over that western us ridge and then southeastward down into the Great Lakes.

    It’s like what one might see during the cold season 🙂

  21. After this thunderstorm threat Sat night into Sun the Mon night Tues time period is another period to keep an eye on.

  23. To Anyone Who Can Help:

    I am considering a climb in the Berkshires very early AM tomorrow, but I can’t get a handle on when rain, if any, would arrive in that part of the state.

    Any estimate would help. Thank you.

  24. SPC must be pulling the hair our of their heads as the 2 say update due at 1:30 is NOT out yet. 🙂

  25. SPC outlook for tomorrow remains unchanged

    https://www.spc.noaa.gov/products/outlook/day2otlk_0600.gif

    https://www.spc.noaa.gov/products/outlook/day2probotlk_0600_torn.gif

    Discussion:

    …Northeast…
    A moderately moist airmass is expected to be in place ahead of the
    approaching shortwave trough and attendant cold front. Early day
    warm-air advection showers are expected, with at least some
    potential for these storms to become surface based as the downstream
    airmass destabilizes during the late morning/early afternoon.
    Additional thunderstorm development is possible along and within the
    warm sector ahead of the front. Strengthening mid-level flow will
    contribute to moderate vertical shear, increasing the potential for
    organized storms. A mix of discrete storms and bowing line segments
    appears likely, with at least some potential for a coherent
    convective line along the front. All severe hazards are possible,
    with damaging gusts as the main threat within any bowing segments.
    More discrete storms could produce large hail and perhaps even a
    tornado.

        1. I “think” the reason for that is that our threat will be later and perhaps will show on the 2-day update at 130 tomorrow AM. We shall see.

          Waiting on 18Z runs to see if there is any change

  29. The jet stream over us Sat night is strong, so that probably negates that the trof and assoc sfc low is weakening slowly on its approach.

    Same thing for the next one, the trof and sfc low reach max strength in the Great Lakes, but that one looks much stronger, even as it slowly weakens on approach.

      1. For instance, here’s the next one at 500 mb after the Mon night/tues one.

        Not out of the norm to have that.

        Difference is, they are usually much further north this time of year with the dynamics passing well to our north.

  33. Quick peak at the latest SREF all areas of SNE except eastern MA at some point in the low tornado risk between 8pm Sat to 2AM Sunday.

  36. From NWS Boston. Western MA and northern CT seem to be the bullseye

    As the night
    progresses, even though heating is lost, they dynamics
    increase as wind fields strengthen. By 09Z, the SREF on the SPC
    website shows 50-70 percent probability of 0-6km bulk shear
    greater than 40 kt across western MA and northern CT. The
    `tornado ingredients` chart highlights that area as well, after
    being maximized in eastern New York earlier in the evening. GFS
    and ECMWF Sigtor levels reach 1-2 and 0-1km helicity is 100-200
    during the overnight hours. Expect isolated to scattered strong
    to severe storms across the region through the night. Lows will
    range from 65 to 70. Patchy fog along the south coast.

  37. Not impressed with weekend threat for the WHW forecast area.

    Too early to do much speculating on early next week, which is why I didn’t. 😉

    1. My brother was outside enjoying it when I left work. 🙂
      He’s not a fan of humidity and there’s enough of a break today that he really likes the air – dew point in 50s.

      1. Your brother and I certainly think alike, at least on that aspect! 🙂

        You, of course are the “oddball” of your family as you like ALL kinds of weather. Sorry but I’m not built that way. 😉

        Hope your brother is doing ok. 🙂

      1. That is awesome. The last season was not the very best I’ve seen. MASH and friends hold that honor but it was up there. The characters grew on me with each season.

Comments are closed.