Saturday Forecast Update

110 Comments

9:17AM

DAYS 1-5…
Today is transition day as a warm front crosses southern New England from west to east with mainly morning showers, clouds lingering most of the day, and increasing humidity, but no heat yet. A very weak disturbance tonight may kick off a couple showers or thunderstorms but it’s likely that most places will not see any. Sunday will be the day of heat and high humidity and more sunshine with only a slight risk of a pop up shower or thunderstorm during the day. Sunday night and Monday will see a trough and a cold front push west to east and create a couple rounds of showers and thunderstorms. The one with the trough Sunday night is 50/50 whether or not it impacts all of the region as it may be dying out on its way through. Monday’s activity is likely to be more widespread and include downpours with local flash flooding, but a lower risk of any strong wind or hail as the timing will be too early in the day. It is always possible that 1 or 2 storms can still attain severe intensity including strong winds, so this will be closely watched. Later Monday look for improvement but a slow drop-off in humidity not really being felt until Tuesday and Wednesday of next week which will both be fair and warm days as we are now in a more typical July pattern.
TODAY: Mainly cloudy. Lingering showers ending west to east by late morning. Increasingly humid. Highs 75-82 though a little cooler in a few South Coast locations. Wind S 10-20 MPH.
TONIGHT: Variably cloudy. Slight risk of an isolated shower or thunderstorm. Muggy. Lows 65-70. Wind SW 5-15 MPH.
SUNDAY: Partly cloudy to mostly sunny and hazy. Slight risk of isolated showers or thunderstorms in the afternoon. Humid. Highs 78-85 South Coast, 85-92 elsewhere. Wind SW 10-20 MPH.
SUNDAY NIGHT: Partly to mostly cloudy and hazy. Chance of showers and thunderstorms mainly late night. Muggy. Lows 67-75. Wind SW 5-15 MPH and gusty.
MONDAY: Cloudy with numerous showers and thunderstorms through midday. Variably cloudy with lingering showers and a slight chance of thunderstorms in the afternoon. Clearing at night. Still humid. Highs in the 80s, some 70s South Coast.
TUESDAY: Partly cloudy. Lows in the 60s. Highs in the 80s.
WEDNESDAY: Mostly sunny. Lows in the 60s. Highs in the 80s.

DAYS 6-10 (JULY 23-27)…
Fair, warm, and dry July 23-24. Hazy, hot, humid potential July 25-26. Showers/thunderstorms may visit by July 27.

DAYS 11-15 (JULY 28-AUGUST 1)…
Look for a pattern of above normal temperatures and below normal rainfall during this period.

110 thoughts on “Saturday Forecast Update”

  1. These links all originally posted by JimmyJames on the previous blog. I apologize if the format is out of whack. The links should still work fine.

    SPC outlook for today. New update around 9am this morning.
    http://www.spc.noaa.gov/products/outlook/day1otlk.html

    6z NAM for Monday still robust. Still think this needs to be cut down some.
    CAPE
    http://meteocentre.com/models/explorateur.php?mod=nam&run=06&stn=CAPE&hh=060&map=qc&stn2=PW&run2=06&mod2=nam&hh2=060&comp=1&fixhh=1&lang=en&yyyy=latest&mm=latest&dd=latest&mode=latest&stn2_type=prog&date_type=dateo
    LIFT
    http://meteocentre.com/models/explorateur.php?mod=nam&run=06&stn=LI&hh=060&map=qc&stn2=CAPE&run2=06&mod2=nam&hh2=060&comp=1&fixhh=1&lang=en&yyyy=latest&mm=latest&dd=latest&mode=latest&stn2_type=prog&date_type=dateo
    EHI
    http://meteocentre.com/models/explorateur.php?mod=nam&run=06&stn=EHI&hh=060&map=qc&stn2=LI&run2=06&mod2=nam&hh2=060&comp=1&fixhh=1&lang=en&yyyy=latest&mm=latest&dd=latest&mode=latest&stn2_type=prog&date_type=dateo

    0z Canadian Model Run For Monday
    CAPE
    http://meteocentre.com/models/explorateur.php?mod=gemglb&run=00&stn=CAPE&hh=066&map=qc&stn2=EHI&run2=00&mod2=gemglb&hh2=066&comp=1&fixhh=1&lang=en&yyyy=latest&mm=latest&dd=latest&mode=latest&stn2_type=prog&date_type=dateo
    LIFT
    http://meteocentre.com/models/explorateur.php?mod=gemglb&run=00&stn=LI&hh=066&map=qc&stn2=CAPE&run2=00&mod2=gemglb&hh2=066&comp=1&fixhh=1&lang=en&yyyy=latest&mm=latest&dd=latest&mode=latest&stn2_type=prog&date_type=dateo
    EHI
    http://meteocentre.com/models/explorateur.php?mod=gemglb&run=00&stn=EHI&hh=066&map=qc&stn2=LI&run2=00&mod2=gemglb&hh2=066&comp=1&fixhh=1&lang=en&yyyy=latest&mm=latest&dd=latest&mode=latest&stn2_type=prog&date_type=dateo

    6z GFS for Monday from Instant Weather Maps. This site doesn’t show EHI Values.
    CAPE
    http://www.instantweathermaps.com/GFS-php/showmap-conussfc.php?run=2015071806&time=INSTANT&var=CAPE&hour=060
    LIFT
    http://www.instantweathermaps.com/GFS-php/showmap-conussfc.php?run=2015071806&time=INSTANT&var=LFTX&hour=060

      1. I was too asleep to look at the radar so don’t know how widespread it was or even the time :). but it poured here.

  4. No golf before noon EDT or 5pm Scotland time.
    To answer an earlier question, apparently Seve Ballasteros won the Open in ’88 on a Monday delayed round.
    This delay would not be happening on the old slower greens. The modern greens are too fast and cannot hold in wind. I hope this causes the greens to be made slower again.

    1. Mac said he thought they’d always been fast here but they made two slower that are higher up and catch more wind. Wind is typical here I guess?? I never have a problem with golfers playing in tougher conditions as long as all have same conditions. I feel as if golfers here are a bit too used to groomed courses. Mac did say yesterday that this year is easier because they had such a wet winter. I thought a drier course would hold the ball in the wind more but he said no. Shows how much I know…or don’t know 🙂

      1. Play resuming at 1230 EDT, according to ESPN.

        The older films of Jack and Arnie reveal them hammering their putts on the old greens. When the golf equipment allowed 300 yard drives, the greenskeepers went to slick greens to prevent scores in the 50s. That is my understanding.

  5. Thanks, TK. My `trough’ begins tomorrow. People talk about the trough of winter as a hard thing to get through. Well, the hardest part of the year for me is the trough of summer. We’ve been lucky thus far, but it looks like heat is on its way: Sweatville and headaches.

  6. Good morning and thank you TK.

    So much for a light shower this morning (from BB last night). WOW! It poured buckets here! (no thunder) I awoke from a sound sleep to run around closing windows.

    TK you still indicated an early frontal passage on Monday. Even the GFS and the SREF
    have come around to a later passage. BB was certain it would be a later passage
    with big boomers around here. Curious as to your reasoning?

    JJ missed a chart from Meteocentre. Since he gave us the NAM and CMC I give you
    this for Monday

    CAPE

    http://meteocentre.com/models/explorateur.php?lang=en&map=qc&run=06&mod=gfs&stn=CAPE&comp=1&run2=06&mod2=gfs&stn2=CAPE&hh2=000&fixhh=1&stn2_type=prog&mode=latest&yyyy=latest&mm=latest&dd=latest&hh=060

    There’s a 5,000 joule bulls eye in there near Boston. Mighty impressive for these parts. Not sure how it will translate into storms, but I would say Severe is quite
    possible.

    LI

    http://meteocentre.com/models/explorateur.php?mod=gfs&run=06&stn=LI&hh=060&map=qc&stn2=CAPE&run2=06&mod2=gfs&hh2=060&comp=1&fixhh=1&lang=en&yyyy=latest&mm=latest&dd=latest&mode=latest&stn2_type=prog&date_type=dateo

    EHI

    http://meteocentre.com/models/explorateur.php?mod=gfs&run=06&stn=EHI&hh=060&map=qc&stn2=LI&run2=06&mod2=gfs&hh2=060&comp=1&fixhh=1&lang=en&yyyy=latest&mm=latest&dd=latest&mode=latest&stn2_type=prog&date_type=dateo

    Note GFS has a WAAAY lower EHI index than do the others.

    SREF has NO tornado threat for our area on Monday. Has a minor threat up North
    today/tomorrow (NOTHING here) as they are near the warm front with more helicity.

  7. A few hours difference either way is going to make a difference on Monday. Certainly ingredients in play for thunderstorms that COULD pack a punch.

    1. From Taunton NWS re: Monday

      SO HAIL AND STRONG WINDS ARE THE TWO MOST LIKELY SEVERE
      THREATS OUTSIDE OF HEAVY RAIN COVERED BY THE HIGH PWATS AND K-INDICES. LOW LVL EHI IS RELATIVELY HIGH AS WELL…SO CAN/T RULE OUT ROTATION IN STRONGER STORMS.

  9. Models continue to amaze and disgust me.

    Looking at the 12Z NAM, although it shows high CAPE, in the simulated radar
    display it shows the prefrontal trough convection coming through between
    6 and 9Z, then NOTHING, until a weak little line forms South East of Boston
    around 21Z. Hmmm

    http://www.instantweathermaps.com/NAM-php/showmap-conussfc.php?run=2015071812&time=INSTANT&var=REFC&hour=042

    http://www.instantweathermaps.com/NAM-php/showmap-conussfc.php?run=2015071812&time=INSTANT&var=REFC&hour=045

    http://www.instantweathermaps.com/NAM-php/showmap-conussfc.php?run=2015071812&time=INSTANT&var=REFC&hour=045

    http://www.instantweathermaps.com/NAM-php/showmap-conussfc.php?run=2015071812&time=INSTANT&var=REFC&hour=057

    I take it there IS something to this…

    TK knows what’s up for sure. Waiting on GFS. 😀

  10. Help me here please. Am I correct that 2500 cape is about base for stronger instability?? So 5000 is extreme? Sorry if wording is not correct but am trying to get straight in my head as we seem to be hearing the term rotation far more often. Thank you

  11. 5000 CAPE is extreme.
    If you have 2500 CAPE that is certainly enough CAPE for strong to severe storms. Sometimes we get High CAPE and Lift Index values but because there is a CAP in the atmosphere when we can’t get thunderstorms to fire. I remember a couple years ago when we had CAPE in the 3,000s and LI in -8 and -10 and commenting here thankfully there is a CAP in the atmosphere otherwise were going to really have to be on the look out.

  12. Never forget what the ‘P’ in CAPE stands for. 🙂

    Not convinced the models have that timing right.

    1. You’re funny TK.

      P for piss poor potential

      Hey nws concerned about sttong
      Storms this pm due to EML (elevated mixed
      Layer)
      Concerned about disctete storms.

      Anything to that?
      There’s convection out there

  14. Cluster of storms has formed in western MA, moving ESE. Wonder if they’ll survive. Sun finally breaking through here in Wrentham.

    1. NWS expects them to weaken, but more to fire around 3-4 PM. We shall see.

      The way I see it, NO ONE has a handle on any of this, but the front runner
      is mostly likely TK. In any case, interesting to see how it plays out.

  15. GEEZ…..I give up.

    12Z GFS for Monday….

    18Z CAPE, yeah right! What Cape. Front passes way early. NO convection during
    daylight hours. Showers overnight with rep-frontal trough I guess.

    http://www.instantweathermaps.com/GFS-php/showmap-conussfc.php?run=2015071812&time=INSTANT&var=CAPE&hour=054

    Reminds me of an old kids game: “Button, button who has the button”

    Which model has the correct solution?
    bah bah bah…….

    One good thing, it won’t be 90 come Monday!!!!!!!!!!

  16. From NWS office, Upton NY for this PM

    WARM ADVECTION SHOWERS/THUNDERSTORMS HAVE PUSHED EAST OF THE FORECAST AREA EARLY THIS AFTERNOON. FORECAST CHALLENGE NOW RESIDES IN THE AMOUNT OF CLEARING AND DESTABILIZATION FOR ANOTHER ROUND THIS AFT/EVE IN ASSOC WITH A SFC TROF AND MID LEVEL SHORT WAVE. 12Z GUIDANCE DIFFERS IN THE TIMING WITH THE LATTER. PREFER LATE AFT/EVE SCT CONVECTION AND WILL EVALUATE FURTHER FOR A POTENTIAL WIDESPREAD EVENT DROPPING DOWN FROM THE NW.

  17. Although the current convection “appears” to be heading a bit South of the City,
    it looks very threatening here now.

  18. Looks like I’m gonna get some heavy rain here in Wrentham… Downpours on the doorstep. Heard one low rumble of thunder, not sure how much thunder and lightning these contain though.

  20. Slid just to the south of me, rumble of thunder and a quick downpour, all done now back to work!

  22. Kind of a double event here- there was a renegade downpour that popped ahead of the main cell- it literally split around me though, only .02″ out of that, when Charlie said he had .24″. The main cell went right over me though, torrential rain and occasional thunder/lightning. 0.36″ of rain total so far, might add a little more but it’s winding down. Rain rate max was 3.31″/hr per my weather station.

    RAP and HRRR did not have this convection at all, they could not possibly have performed worse today.

    1. Nws said they would weaken. If so, not by much and not by what you describe.
      Let’s see if there is more later.

    2. Now east of your location, echoes are diminishing. Held together Much longer
      than predicted by NWS. 😀

      1. From NWS

        TSTM CLUSTER NOW MOVING THROUGH SOUTHERN NEW ENGLAND WAS NOT WELL HANDLED BY HIGH RESOLUTION MODELS AND SEEMS TO HAVE HELD TOGETHER SOMEWHAT SURPRISINGLY WELL GIVEN LIMITED INSTABILITY TO WORK WITH.

  23. Saw blue sky here for about five minutes….that was it.

    That cell may be headed Sue’s way??

        1. You are CORRECT!

          For some reason, I though Halifax was a bit more North
          than it is. YUP, hitting there now. Nothing dangerous, just
          some brief heavy rain.

      2. Halifax is right in my back yard a 5 minute car ride. Depending which way I turn I can be in Hanson , Halifax , marshfield or duxbury in no time at all. I suspect you may be talking about earlier maybe 2 or so as I was planting in the yard and for sure looked like a decent rain storm even the rumble of thunder in the air but barely a sprinkle came out of it.

          1. Yea I was going to vac the pool but with the thunder and dark sky I held off. Today I planted a bloomarang lilac and a rose bush. I’ve been plating permanent plants all around the yard and pool area such as lilacs, hydrangea , multiple rose bushes, day lilies , hosta, black eyed Susan . Also creating beds around the yard.

              1. My wife wanted a lilac bush and the nursery said this kind is the one to get as it flowers late spring than takes a break till the end of July where it blooms a second time till frost. I’ll see no experience with this one. It needs full sun and it has that and also needs to be in moist soil so two soakings a day. I also fertilized it.

                2. Our was not in full sun and bloomed twice for three yrs. then ice from roof killed it. I love them. You will enjoy

  25. From Taunton NWS

    NEAR TERM /UNTIL 6 PM THIS EVENING/…
    ***AN ISOLATED STRONG TO PERHAPS MARGINALLY SEVERE THUNDERSTORM OR TWO IS POSSIBLE LATE THIS AFTERNOON AND EARLY EVENING ACROSS
    PORTIONS OF INTERIOR SOUTHERN NEW ENGLAND***

      2. Where you headed? Don’t tell me you’re attending the
        Foo Fighter’s concert at Fenway?

              1. Son and friends do also. There is a restaurant in sudbury that has a jazz brunch on Sunday’s. Bullfinches

  27. Some strong wording from Taunton NWS office regarding tomorrow evening:

    FIRST LOOK AT SOME OF THE 12Z MODEL GUIDANCE IS VALIDATING
    CONCERN FOR POTENTIAL OF STRONG CONVECTION SUN EVENING/NIGHT.
    ANTICIPATE A CAP WILL KEEP AREA IN CHECK THROUGH THE DAY ON SUN
    BUT THINK THAT CAP WILL ERODE TOWARD EVENING AS UPPER SHORT WAVE TROF AND PREFRONTAL SURFACE TROF APPROACHES FROM THE WEST. LOOKS LIKE SOMETHING OF AN EML TO WORK WITH AND EVIDENCED BY RELATIVELY IMPRESSIVE MID LEVEL LAPSE RATES APPROACHING 7C/KM…TOTAL TOTALS REMAINING WELL ABOVE 50 INTO THE NIGHT AND Showalter Index GENERALLY -4 TO -5. THE 12Z GFS NOW INCREASES THE VERTICAL SHEAR CONSIDERABLY BETWEEN 00Z AND 06Z MON. CONCUR WITH A COUPLE OF SURROUNDING OFFICES THAT WE MIGHT EVEN HAVE TO BE ON THE LOOKOUT FOR A DERECHO

    Link for Total Totals: http://www.theweatherprediction.com/habyhints/302/
    Link for Showalter Index: http://www.theweatherprediction.com/habyhints/301/
    Link for EML (Elevagted Mixed layer): http://bangladeshtornadoes.org/EML/emlpage.html

  28. SPC has slight risk far western MA and marginal risk up for all but eastern sections for tomorrow.

  33. Ended up with .07 here. Shows what a localized effect this had since WxWatcher and Charlie had quite a bit more not so far away.

  34. 12Z 15KM ARW WRF Vorticity Generation Potential

    http://www2.mmm.ucar.edu/prod/rt/wrf/wrf20/2015071812/vgp.hr39.png

    http://www2.mmm.ucar.edu/prod/rt/wrf/wrf20/2015071812/vgp.hr42.png

    http://www2.mmm.ucar.edu/prod/rt/wrf/wrf20/2015071812/vgp.hr42.png

    Note much of the area has an index of .3, with a few stripes of .4 thrown in for goof measure. In general: Vorticity Generation Potential (VGP = shear*CAPE**0.5) should > .27 for significant tornadoes. Just something to watch.

    It looks like we “may” have an unusual situation tomorrow might with Significant
    Night time instability. Not good. Not good at all. “Hopefully” all we get out of it
    are some strong storms with winds to 40-50 mph tops and heavy rain. Keep our
    fingers crossed.

    1. Some more on Tornado Forecasting:

      Forecasting

      Previously, people looked for high CAPE, high 0-3km Storm Relative
      Helicity (SRH), and EHI > 1-2

      Now, other parameters are favored more. In general you want a warm RFD
      and lots of low-level stretching. Thus,
      LCL height < 800 m is needed for significant tornado (low LCLs are good)
      MLLCL 65% (dew point depressions at surface of 10-11 F or less)
      LFC height < 1303 m for F2 or stronger, average for any tornado is 1499
      m, for supercells without tornadoes, it is around 1890 m
      0-1 km EHI (median for sig tornadoes is 2.1, for weak it is 1.4)
      0-1 km SRH (165 average for sig tornadoes, 137 for weak)
      0-3 km CAPE (F2-F5 tornadoes usually have around 100 J/kg or more)
      MLCIN .27 for
      sig tornadoes
      0-1 km bulk shear > 15-20 knots for good tornadoes
      In general, you want: (1) “moist” low-levels (high RH, low
      LCL)
      (2) good stretching potential down
      low (0-3 km CAPE, 0-1 km EHI, LFC, CIN)
      (3) good low-level shear (0-1 km
      SRH, 0-3 km VGP)

  35. We don’t often get severe weather in the overnight hours and this may be one of those times where the dynamics will be able to off set no daytime heating.

    1. I fear that is the case. Taunton NWS is worried for sure. I don’t like the
      VGP index values especially combined with the EHI numbers we are
      seeing from the CMC and NAM (not so much on GFS).

  36. Not much happening to our West. These won’t make it to our area, at least I “think” not.
    Will something else pop? I honestly think not, but one never knows.

  37. We been talking for about a week now about this time period 19th -21st as a time frame to watch for thunderstorms and looks like we very well maybe seeing them.

  38. 18Z NAM for 03Z Tomorrow Night:

    CAPE

    http://www.instantweathermaps.com/NAM-php/showmap-conussfc.php?run=2015071818&time=INSTANT&var=CAPE&hour=033

    Simulated Composite reflectivity

    http://www.instantweathermaps.com/NAM-php/showmap-conussfc.php?run=2015071818&time=INSTANT&var=REFC&hour=033

    4Z

    http://www.instantweathermaps.com/NAM-php/showmap-conussfc.php?run=2015071818&time=INSTANT&var=REFC&hour=034

    5z

    http://www.instantweathermaps.com/NAM-php/showmap-conussfc.php?run=2015071818&time=INSTANT&var=REFC&hour=035

    That’s Serious Rain there.

    1. Same here. Very Dark, but nothing shaking.

      Where are you headed for Dinner in Cambridge? Curious as I am not aware
      of too many restaurants in Cambridge.

  41. From NWS Taunton
    ***POTENTIAL FOR SIGNIFICANT SEVERE WEATHER OUTBREAK SUNDAY
    EVENING WITH ISOLATED STRONG TO SEVERE STORMS POSSIBLY LASTING
    WELL INTO THE NIGHT***

    WE ARE CONCERNED THAT THE CAP WILL ERODE ENOUGH SUNDAY
    EVENING TO ALLOW STRONG TO SEVERE CONVECTION TO DEVELOP IN
    MODERATE TO HIGH INSTABILITY AND INCREASING VERTICAL WIND SHEAR.
    THERE LOOKS TO BE AN ELEVATED MIXED LAYER WITH MID LEVEL LAPSE
    RATES EXPECTED TO APPROACH OR EVEN EXCEED 7C/KM AFTER 00Z MON.
    MODEL CONSENSUS INDICATES THAT TOTAL TOTALS WILL RISE TO BETWEEN
    50 AND 55 AND SHOWALTER INDICES BELOW -4. VERTICAL WIND SHEAR IS
    INITIALLY A MODEST 25 TO 30 KT IN THE EARLY EVENING BUT INCREASES
    TO 35 TO 40+ KT BY AROUND MIDNIGHT. THINK WE COULD SEE ORGANIZED
    STRONG TO SEVERE TSTM LINE SEGMENTS WITH POSSIBLY A FEW BOW
    ECHOES. HEAVY DOWNPOURS WITH PWATS 1.5 TO 1.8 INCHES…SOME HAIL
    AND PROBABLY FREQUENT LIGHTNING ARE ADDITIONAL HAZARDS FOR SUNDAY
    EVENING INTO SUNDAY NIGHT.

  42. Hi all!

    I’m heading to Salisbury Beach this evening. Night ends with nice fireworks on a barge just off the beach. You’ll really start to feel the humidity as the evening goes on, unless of course you are in AC.

    I have my concerns for that stuff Sunday evening / night. If you recall, I mentioned Sunday night storms are a possibility during yesterday’s chats. Good support may be realized in big storms but they may be confined to NH and far northern MA. We’ll have to see how that plays out. It’s about 28-32 hours away.

    Monday’s activity should pretty much be the first half to 2/3 of the day and again heavy rain is the main threat. I don’t agree with NWS’s earlier assessment on this.

    More later… Good evening everyone!

    1. Thank You TK. Enjoy this evening.

      re: tomorrow night

      Any concerns over possible rotating storms?

      Is the Vorticity Generation Potential chart useful at all?

      Thanks

      1. It’s “ok”. I have a slight wonder about that. I’m going to consult with my fellow met’s later tonight.

        1. VGP index for tomorrow night is .3 to .4.
          EHI values are roughly in the range of 2-4.

          However, the SREF tornado indices are just not there, so
          I’m not sure.

          Many thanks. Should you come to a consensus, could
          you post IF you have a chance.? There are definitely
          interested parties here.

  43. re: tomorrow night

    Surface winds forecast to be SSW
    925 MB Winds forecast to be SW, veering to West
    850 MB winds forecast to be West
    700 Mb Winds forecast to be WSW TO West
    500 MB also pretty much West

    Is that enough? Not sure, but IF we were to get a strong enough storm, I “think” the potential is there to rotate.

  44. Some convection about to move into the Berkshires at nearly 6PM.
    If and that is a big if, they survive the Eastward trip, we’re looking at something
    like 9-11 PM or so.

  45. OS. We went to Summer Shack in Fresh Pond. It used to be really great. Not so much tonight and price went up

    Son really enjoys Russell House Tavern (I think is name) in harvard square but also several other really good restaurants in cambridge. I can get names if you like

    As I looked behind us heading home west on Rt 2, it looked quite a bit darker over Boston. I don’t see anything on the radar

  48. Another good lesson on why modeling is far from perfect. A couple days ago who would have thought all the “action” would be this evening and early tonight and tomorrow would be a dry day?

    And who would have added a chance of showers or thunderstorms to Tuesday’s forecast with any confidence?

    That’s right…nobody. 🙂

    This is why updating forecasts is so necessary, and why taking a forecast 4-days out and running with it is generally not always the best idea. If updates are available, make use of them! This time they will have an impact, because Monday evening will be a much better evening to take that walk around the pond, for example, than this evening will probably be.

    And speaking of an update, I’m working on one now and will have it posted as soon as possible! Good morning all. 🙂

    1. :). And NWS was going with Euro slower timing because of its consistency and ignoring the faster GFS!

      1. But it hadn’t been consistent, which is one of the things that confused me.

        I always thought we may have a shot at stuff this evening from a pre-frontal trough, which is actually more the case then ever, but I gave the front itself enough credit for tomorrow when in fact it’s almost a non existent front, and a second front comes along late Tuesday which has a more significant air mass change behind it.

        Think of it this way: You stand on the shoreline and watch waves come in over relatively flat sand, so they have time to run out. It looks like some of them are strong enough to make it to your feet but they just run out of steam and never reach you, then another one will come along and make it to you. You can watch this succession of waves with fascination and try to predict which ones will make it and which ones won’t. Try it. You’ll find out that you’re not correct every time and your error will increase the sooner you try to predict a wave versus when it gets closer to you. To me, that is a perfect analogy to weather forecasting, and more specifically forecasting a series of troughs and fronts.

        1. Indeed. Nicely done. PERFECT!!!

          btw, did you come to some sort of conclusion on
          the possibility of any rotating storms. I see nothing
          but conflicting data. Best I can tell is that conditions
          would be marginal at best for that, so There is a chance
          but likely not. Is that reasonable? thanks

        2. TK predicting waves is just one of my fascinations with the ocean. Perfect analogy. The Mets should use it….a lot. And as I read your entire post, which is excellent, it brought home once again what the TV mets have to deal with. They are expected to get forecasts out 4-7 to sometimes 10 days in advance.

          Great write up. Thanks

  49. TK, your thoughts on the HRRR and RAP for today’s use?
    Predicting those wave too soon? 😆

    Each model is different.

    GFS has the lowest Cape for anytime today. Tops = 1,000 to 1,500 Joules.
    NAM is up to 3,000 to 3,500 as is the CMC.

    Frankly, I’m not sure what to expect today until it arrives. Can’t trust any of
    these models.

  50. It’s 8:24 AM and it’s already up to 77.7 here.
    Logan dew point up to 71. It’s going to be a STINKER today and I mean
    a STINKER. Really the best possible fuel for any thunderstorm development.

  51. I keep seeing the models showing veering winds with height

    Surface = SSW to SW
    925 MB (2600 feet) = SW to WSW
    850 MB (5000 feet) = West
    700 MB (10000 feet) = NorthWest

    Perhaps most of the veering takes place to high and there is not enough
    low level veering. Just not an expert and trying to see when we should be
    concerned and when we shouldn’t be.

  53. Ok, the NWS discussion from about 4 hours ago have 2 scenarios.

    1. The action stays to our North closer to the NH border and the rest of Southern New England remains dry.
    2. The action develops into a mesoscale convection complex and dives Southward
    and affects most of the rest of SNE.

    If I recall, TK indicated yesterday that the main action “could” be to the North.

    Stay tuned for later updates.

    For good reading here is the link: http://forecast.weather.gov/product.php?site=NWS&issuedby=BOX&product=AFD&format=CI&version=1&glossary=0&highlight=on

    1. convection => convective
      My hands don’t listen to my brain. In fact nothing listens to my brain.

      1. Good luck to Mrs. OS today on this heat and humidity. Hopefully you put the AC’s back in for her today :).

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