Thursday Forecast

50 Comments

6:43AM

DAYS 1-5 (JULY 19-23)
Not alot to change on today’s blog compared to yesterday’s. High pressure in control with a few very nice days upcoming. You will notice a slight increase in humidity by Saturday but not to the point of great discomfort. However, when low pressure moves through from south to north early Sunday this will lead high humidity into the region, introducing a new weather pattern, the much-touted building ridge off the East Coast, trough in Great Lakes & Midwest, and larger ridge in the western USA setup. Forecast details…
TODAY: Mostly sunny. Highs 78-85. Wind light variable with coastal sea breezes.
TONIGHT: Mostly clear. Lows 58-65. Wind light variable.
FRIDAY: Mostly sunny. Highs 77-86, coolest in coastal areas. Wind light variable with sea breezes.
FRIDAY NIGHT: Mostly clear. Lows 58-65. Wind light variable.
SATURDAY: Partly cloudy. More humid. Highs 77-86, coolest coastal areas. Wind light E to SE.
SUNDAY: Mostly cloudy. Showers likely. Humid. Lows in the 60s. Highs in the 70s.
MONDAY: Partly sunny. Chance of showers and thunderstorms. Humid. Lows in the 60s. Highs from the middle 70s to middle 80s, coolest coast.

DAYS 6-10 (JULY 24-28)
A large scale pattern of ridge West, trough Midwest / Great Lakes, ridge off East Coast means a period of higher humidity and opportunities for showers and thunderstorms on a daily basis, but these chances will be lowest July 24-25 and again by July 28, with a couple days of greater shower/storm risk July 26-27. Temperatures will run near to slightly above normal.

DAYS 11-15 (JULY 29-AUGUST 2)
A similar pattern should continue through the final days of July and the very beginning of August as well.

50 thoughts on “Thursday Forecast”

  2. Thanks TK. Yet another sensational day on the way in what has been one of the best summers, weather-wise, that I can remember.

    Really interested in how the new pattern plays out. If we get a third of the rain the 6z GFS shows for the next two weeks, we’ll drown out the drought. If we get the whole thing, we’ll have some serious flood risks. I would be surprised if most places get any more than half of these totals though.

    https://www.tropicaltidbits.com/analysis/models/?model=gfs&region=neus&pkg=apcpn&runtime=2018071906&fh=384

  6. Good morning and thank you TK. Yet another 10. I can’t believe the number
    of #10 days we have had this Spring/Summer. GORGEOUS!!!!

    1. I just need it to continue up north next week . I can handle a rain day Sunday first day but just need it decent the rest of the week . One more 12 hr shift tomorrow & it’s game on .

    1. Did you see in the NWS discussion their early thoughts on watching the warm front sometime around Sunday …….

      1. It’s under the long term portion.

        The mini title above the paragraph is Saturday night/Sunday

        1. Tom, no I haven’t had a chance to look. Quite busy
          at the office, but You have compelled me to take a peek. 😀

      2. Ahah…. got it.

        You, of course, meant this:

        Saturday night/Sunday…

        Very anomalous weather pattern evolving with robust northern stream trough entering the OH valley and taking on a negative tilt along the eastern seaboard. In addition, trough-ridge half wavelength collapsing, providing vigorous cyclonic flow aloft across southern New England. At the surface this gives way to an impressive baroclinic wave traversing NJ with attending warm front approaching southern New England. Two concerns with these features, very anomalous low level southeast jet of +3 standard deviations will result in tropical moisture surging northward with PWATs over 2 inches advecting across southern New England. Thus torrential downpours possible given strong forcing for ascent within this tropical airmass. In addition anomalous low level jet will provide elevated instability. Further more low level inversion weakens in approaching warm sector as dew pts climb into the low 70s. Thus low LCLs combined with strong low level shear vicinity of warm front will have to be watched for possible rotating T-storms late Sat night into Sun morning. Improving/drying trend Sunday afternoon as
        front lifts north and warm sector overspreads the region along with dry slot aloft

        😀 😀 😀

        BTW, as soon as you posted that above I KNEW exactly
        what was going to be discussed. NO doubt about it!!!!

        Must have been prepared by TORNADO TED.

        On a serious note, this set up seems similar to the set up
        for the Revere tornado, except it appears to be
        much more robust.

        And THANKS Tom.

  10. Just thinking…. Did I ever say HOW MUCH I ENJOY this BLOG?
    and VERY MUCH appreciate the dedication put forth by TK to present
    this to us all.

    THANK YOU TK!!!!

      1. I totally agree!!! You all are great and fun folks!!! Great place to be for discussions on severe weather and Dairy Queen!!! 🙂

        Thanks for all of your efforts, TK, each day!!!

  11. Regarding the above discussion from the NWS regarding Early Sunday AM.

    Here are the 6Z NAM Helicity charts.

    0-1KM

    http://maps1.pivotalweather.com/maps/models/nam/2018071906/075/srh01.us_ne.png

    0-3KM

    http://maps1.pivotalweather.com/maps/models/nam/2018071906/075/srh03.us_ne.png

    These levels are about as high as i have ever seen around these parts.

    LCL heights are UNDER 100M….very very low.

    http://maps1.pivotalweather.com/maps/models/nam/2018071906/075/sblcl.us_ne.png

    LCL

    Lifting Condensation Level (LCL)
    The Lifting Condensation Level (LCL) is the level at which a parcel becomes saturated. It is a reasonable estimate of cloud base height when parcels experience forced ascent. The height difference between this parameter and the LFC is important when determining convection initiation. The smaller the difference between the LCL and the LFC, the more likely deep convection becomes. The LFC-LCL difference is similar to CIN (convective inhibition). LCL heights from approximately 500 m (1600 ft) to 800 m (2600 ft) above ground level are associated with F2 to F5 tornadoes. Low LCL heights and low surface dewpoint depressions (high low level RH) suggest a warm RFD which may play a role in tornado development.

    This would all happen with a LOW CAPE environment:

    http://maps1.pivotalweather.com/maps/models/nam/2018071906/075/mucape.us_ne.png

    1. Waiting on latest 12Z runs.

      Noting above, NOTHING can happen IF we don’t get a decent thunderstorm
      in the first place, BUT given the conditions, “should” one develop then a Revere
      type situation “could” occur someplace(s) In SNE sometime Sunday AM.

  12. Biggest threat in our area would be around or just before 8AM Sunday AM with
    this convection, assuming it would ever exist in the first place. 😀 😀

    http://maps1.pivotalweather.com/maps/models/nam/2018071912/072/refcmp.us_ne.png

    We’ll just have to carefully watch and see.

    I just keep thinking back to that Revere situation.

    It was a low cape/high shear environment, but a Thunderstorm got going, in fact it
    was a pretty good one and I saw some evidence of rotation well SW of the city
    out by Franklin or so. Then is subsided, only to start re-emerging just
    about over the City of Boston with touch down in Revere.

    So, we cannot dismiss this out of hand. Must be watched, but hopefully and perhaps likely, nothing more than showers and garden variety T-storms.

  13. Interesting to note that other than the possibility of some thunderstorms, NOT
    a word about helicity or the potential of rotating storms. NOT ONE WORD.

    1. Duh,……… that was supposed to day the UPTON, NY NWS had nothing
      to say about rotating storms.

  14. Are my old eyes seeing corectly that the 12z NAM has the coastal system at 999mb coming into NYC ?

    Now, 999mb isn’t terribly strong, but it’s a 5-7 mb decrease against the 00z NAM projection.

  15. 12Z Euro would have our rain system pass farther East than its American and Canadian
    counterparts.

    http://www.instantweathermaps.com/ECMWF-php/ecmwf.php?run=2018071912&region=USA&var=PRMSL_msl&hour=072

    Waiting on my service to get updated severe parameters which on this run
    I would expect to be farther East as well.

    Getting interestinger and interestinger.

    Btw,

    NYC (Upton), Portland. ME (Gray) and Albany NWS offices all make NO MENTION
    of the possibility of rotating storms. Not even an inclining.

      1. I’ll have more in a few. My Euro Service is showing
        a Moderate to High Tornado Threat. Will post some maps
        shortly. I make no claims to the accuracy of the maps, but
        I can tell you that the proprietor of the site is a full-fledged
        qualified meteorologists and fully stands behind his product.

    1. Euro has center passing through Central Connecticut. Given that path
      and low level helicity, that is about in the worst possible location
      for us.

  17. Thanks JP Dave & all!

    “Highly anomalous?” I don’t agree with “Tornado Ted”. It’s not really that anomalous at all. We’ve seen it many times during transition to the pattern we’re heading into.

    1. 😀 😀 😀

      I discuss this character at the Taunton, now Norton office, all of the time with my wife at home. I honestly think there is a forecaster (I have Dubbed “Tornado Ted” ) in that office that can’t wait to insert rotating thunder storms or Brief spin ups and the like into the discussion whenever the conditions might remotely favor it.

      Given all of that, TK do you see any threat at all?

      Frankly, I was quite surprised to see my Euro service advertising
      a real threat.

      The threat is likely low, but I strongly suspect that the probability of occurrence is NOT zero.

      1. Because we are looking at a fairly tight circulation by summer standards, some of the low level wind shear will be in place, similar to in a tropical system, so I couldn’t argue with a low threat – the type that produce brief EF-0 & EF-1 type tornadoes. Things will have to come together just right.

        1. Thank you sir. Makes perfect sense to me.

          So would these be possible even without an actual
          thunder storm? I think we had this discussion before.

          I guess I’ll be up early Sunday just in case.
          Crap, I was planning on fishing Sunday AM. Doesn’t
          look like that will happen. 😀 😀

  18. The experimental or “parallel” GFS from 12z today has a pretty good handle on the upcoming pattern in my opinion. Loop the radar simulation to see that it is not going to be “rainy for days” as some media and especially misread weather apps have lead people to believe. Not saying the timing is spot on, but I think its forecast is very good through at least July 27.

    1. Keeps almost all of the helicity well to our West and doesn’t rain
      much on Eastern Sections.
      large disparity between this run and the Euro run.

  20. According to Eric, the wettest days next week will be Monday and Thursday. I get the impression though that no day will be completely dry either.

    1. Depends on where you are. I can assure you that at least 3 days next week there will be many places that see no rain at all.

  22. We’re supposed to be sailing from Scituate to the Cape Cod Canal Sunday morning. Should we consider shifting this plan to Saturday? We need about four hours for the journey and would need to arrive at the canal entrance around noon Sunday to catch the tail end of the favorable current or an hour earlier on Saturday.

    1. Amy Harvey has the first part of Sunday as very wet than drier & humid later afternoon if this helps you . Saturday’s forecast is pretty much dry till midnight

Comments are closed.