Wednesday September 25 2024 Forecast (7:30AM)

87 Comments

DAYS 1-5 (SEPTEMBER 25-29)

The blocking pattern in place stays in place through this forecast period. High pressure at the surface is far enough north that an east to southeast flow off the ocean drives broken marine layer clouds into our region while a trough approaching from the west spreads its high to mid level clouds in. Summation: A generally cloudy day today. Low pressure associated with the approaching upper trough is expected to track just north of the region on Thursday. Its warm front will bring a bout of rain early morning to midday Thursday, and its cold front will likely bring a briefer period of moderate to heavy showers and possible thunderstorms, with a brief break in between. This system will move off to the east southeast Thursday night and early Friday with a clearing trend will take place, and high pressure again builds to the north of the region. With this we see a return of dry weather Friday and over the weekend. Meanwhile, strengthening Tropical Storm Helene, soon to be a hurricane, will track northward through the eastern Gulf of Mexico and its landfall point is most likely on the eastern part of the Florida Panhandle. Big trouble for that region with rain, wind, and coastal storm surge. Thankfully it appears the core of that hurricane will come ashore in a relatively sparsely populated area, lessening the property impact aspect. Often when we see these systems down there, we hear from their remnants eventually. We will, and we won’t. Huh? What does that mean? It means this. Friday night and Saturday the cloud shield will make it into our sky. It remains to be seen how thick it will get in terms of a limiting factor for Saturday sunshine, but I’ll take a look at that as we get closer to it. Blocking high pressure will keep the rainfall from the system far to our south, hence the dry forecast.

TODAY: Mostly cloudy. Highs 62-69. Wind SE up to 10 MPH.

TONIGHT: Cloudy. Rain arrives west to east overnight. Patchy fog forming. Lows 53-60. Wind SE up to 10 MPH.

THURSDAY: Cloudy. Rain likely until mid afternoon, tapering west to east. Patchy fog. Highs 61-68. Wind SE to S 5-15 MPH.

THURSDAY NIGHT: Cloudy. Moderate to heavy showers and possible embedded thunder moving northwest to southeast across the region. Areas of fog. Lows 52-59. Wind S 5-15 MPH shifting to NW.

FRIDAY: Early morning showers exit the South Coast as clouds diminish. Sun and passing clouds mid morning on. Highs 63-70. Wind NW 5-15 MPH.

FRIDAY NIGHT: High clouds increasing south to north. Ground fog patches forming in lower elevations. Lows 46-53. Wind N diminishing to under 10 MPH.

SATURDAY: Filtered / dimmed sun. Highs 62-69. Wind NE 5-15 MPH.

SATURDAY NIGHT: High clouds decrease north to south. Ground fog patches forming in lower elevations. Lows 45-52. Wind NE diminishing to under 10 MPH.

SUNDAY: Filtered to brighter sun. Highs 62-69. Wind NE 5-15 MPH.

DAYS 6-10 (SEPTEMBER 30 – OCTOBER 4)

Blocking high pressure is expected to keep tropical moisture to our south early in the period. Some remnants of that moisture combined with a trough from the west will bring a brief period of unsettled weather in the October 1-2 time window before fair weather returns. Temperatures variable, moderating early in the period, cooling late period.

DAYS 11-15 (OCTOBER 5-9)

A early-period unsettled interlude as the pattern shifts from blocking to quasi-zonal (more west to east flow). No temperature extremes expected.

87 thoughts on “Wednesday September 25 2024 Forecast (7:30AM)”

      1. It is …..

        https://www.star.nesdis.noaa.gov/goes/conus_band.php?sat=G16&band=09&length=24

        And there’s the upcoming interaction with the dropping upper low in the central US. Right now, I think its helping to enhance the outflow in the northern quadrant.

        Its also going to give Helene forward speed at landfall and the models are screaming of a system still in the 970s mbs all the way thru GA and low 980s even into eastern TN

        The inland event is going to be surprisingly strong.

  2. Goid morning and thank you TK

    Some of the hurricane models are quite disturbing. will post some links soon.

    NHC now maxes it out at 120 mph.

    some models suggest much highrr. we shall see.

  3. Here is the 6Z HAFS-B hurricane model.

    https://www.tropicaltidbits.com/analysis/models/?model=hafsb&region=09L&pkg=ref&runtime=2024092506&fh=33

    Now 908 mb is a monster of a storm. usually would be a full blown Cat 5

    HAFS_A hurricane model

    https://www.tropicaltidbits.com/analysis/models/?model=hafsa&region=09L&pkg=ref&runtime=2024092506&fh=42

    929 MB would be a high end cat 4

    HMON hurricane model

    https://www.tropicaltidbits.com/analysis/models/?model=hmon&region=09L&pkg=ref&runtime=2024092506&fh=42

    947 mb would be a high end cat 3 or low end cat 4

    ditto HWRF

    https://www.tropicaltidbits.com/analysis/models/?model=hwrf&region=09L&pkg=ref&runtime=2024092506&fh=45

    Take your pick, they are all bad, but to me, the trend is for a stronger system. I suspect the next update from the NHC will increase the wind to 125 mph or perhaps even 130. We shall see.

    For your reference, here is the Saffir-Simpson Scale and it gives a reasonable idea of pressures and wind speeds.

    https://ibb.co/ypRRCvw

  5. Thanks TK! I can not understand what is taking Major League baseball so long to make a decision on the Mets Braves series in Atlanta. This series has huge playoff implications. Kemp has already declared a state of emergency in Georgia and nothing from MLB. Are the Mets supposed to wait this out and then risk getting stranded there and not get to Milwaukee for the opener of that series? No foresight by MLB at all!

    1. All I can say is: $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$

    1. But catching up.

      It was in the high 980s/low 990s yesterday.

      As we get closer, I think it will continue lower with successive 00 and 12z runs.

  16. Thanks TK.

    Helene now officially a hurricane. Intensity forecast continues to creep up. It’s possible it could become a Cat 4+ storm, although its very large size works against it in terms of maximizing wind speed. Instead, a storm with this structure tends to spread winds out over a larger area, which ultimately results in greater impact overall.

    The track forecast is holding, so my concerns for Tampa in particular have been largely assuaged. But the reality is, even if the center comes ashore in a rural area, Helene’s large size will make it a devastating storm for a huge area of the Southeast US, including places well inland. This will likely be a top 10 costliest hurricane in US history.

  19. From a model perspective, HMON/HWRF are king at this stage. However, global models like the GFS, EC, ICON and their ensembles do continue to provide good value even this late in the game since we’re talking about a synoptic size system. I don’t particularly care for the HAFS, they’re just way too inconsistent. I consider them more of a developmental product, their technology is the future, but they aren’t “there” yet.

    The NAM (especially 3km NAM), HRRR, WRFs, FV3, RGEM are absolute “do not use”. They are not designed for tropical and will be wildly wrong. The only exception is that once Helene starts to become extratropical, then these models start to provide value.

    1. Thank you WxWatcher. I gathered that the HRRR was useless
      and knew about the NAMS, but did NOT know how
      those others were. THANK you for that info.

      Nice to know about the HAFS A&B.

      Well the HWRF and HMON are forecasting very low end CAT4 or highest level CAT 3. That seems to be what we will
      be looking at.

      Again, many thanks for this input.

      1. Of course, always enjoy seeing your posts!

        One other thing to watch – Helene’s max winds will tend to under-perform its pressure. Another product of its large size. It’s currently 979mb which is usually more typical of a high end Cat 1 or Cat 2 storm. For Helene to reach Cat 4 intensity, my estimate would be you’d likely need to see a pressure in the 920’s or low 930’s. FWIW, the HWRF indicates its pressure could drop close to 940 yet still have it “barely” at major hurricane intensity. Doesn’t make it less dangerous, it’s just about how all that mass and momentum are distributed…

  21. Portion of discussion from NHC

    Rapid Intensification (RI)
    indices indicate a high chance of RI during the next 24 hours, and
    as a result the NHC intensity forecast shows Helene becoming a
    major hurricane by Thursday morning. There is still some
    uncertainty on exactly how strong Helene will get, and upward
    adjustments to the forecast intensity could be required in
    subsequent advisories if Helene rapidly intensifies more than
    forecast. Regardless, Helene is forecast to be a large major
    hurricane when it reaches the Big Bend coast of Florida.

  22. Based on a comment above by Tom (I think Tom), I did some searching to see what hurricane maintained hurricane strength the furthest inland.

    I found Hazel by there seems to be some discussion as to where it became extra tropical. I also saw Ike mentioned. If memory serves, I believe Hugo was around 200 miles inland. I know it caused significant damage in Charlotte but don’t know if it was hurricane strength.

    Anyone have better info??

  28. Thank you, TK.

    Briefly on sports. I’m a loyal fan of the local teams (even if I’m in the UK at a certain point in a few years time, I will never lose my attachment to Boston teams, win or lose). I can be cranky, but my rational self knows when to temper the crankiness.

    Vicki, that is very cool that a local kid – Sutton – is a starter for the White Sox. I think we all forget that even the worst MLB team still fields players who are living the dream of being in the 0.001% of baseball players who aspire to being in the big leagues someday. Similarly, even if the Patriots turn out to be the worst NFL team this year (far from certain; right now they’re better than a team that some pundits picked to be in the AFC championship game, the Bengals) their roster includes elite football players, among the 0.001% (I’m very much guessing with this number) of aspiring athletes who want to be in the NFL someday.

  31. I guess Ian’s storm surge in Ft Myers was 14 ft

    I assume many saw that video of the incredible storm surge.

    The NHC is now forecasting 12-18 ft east of landfall.

  34. “ Shrimpers who rode out the storm on their boats speak of measuring gusts in the 160 to 180 mph range. Additionally, Hugo’s waters wreaked havoc, flooding the Charleston peninsula and completely covering the barrier islands. In the fishing village of McClellanville, the storm surge was nearly 20 feet high.”

      1. I had thaf same thought as I watched. I don’t know if the shrimp boats are better docked or out to sea but I sure would not want to be on one.

    1. The NHC, I think I saw, spoke of the eastern eye wall side forming hours ago, but I’d say it’s putting the entire eye wall together now.

  36. New recon plane entering Helene. My guess is they will not find a substantially stronger storm. It has definitely been entraining dry air all day, hence the somewhat ragged satellite appearance.

    However, it’s also very symmetrical with excellent outflow (low shear) and over very warm SSTs. If that dry air mixes out, a more rapid intensification period is very possible and probably likely by late tonight or tomorrow morning. Beware of any calls of “bust” even as it is likely to fall short of near term intensity forecasts (I.e., I don’t think we’ll see the forecasted 100mph by 0z this evening)…

  37. Our city’s trash / recycle / yard waste pickup company provided us all with new rolling recycle bins and the program to pick those up begins next week (the week after for me since this week is my recycle week and we go every other week). However, the bins can easily fit a month’s worth of recycling in them. Might have to put it out only every 4 weeks. 😉

    1. These are the ones that the truck arms lift in to dump into the truck? We don’t have trash pickup in sutton so need to hire our own company. We have trash and recycling each week but there are six in the house so fill them.

    1. It’s going to come across the perfect combo of warm water and divergence aloft with no shear. This is what makes these atmospheric heat engines work best. Ironically, they are doing an important job. We just sit in the way a lot.

  39. From Ryan Hanrahan on Hurricane Helene

    Hurricane Helene is a dangerous storm. Serious storm surge flooding on the Florida Gulf coast, destructive winds from the Florida panhandle north into Georgia (possibly including Atlanta), and heavy rain leading to severe inland flooding.

    Helene really looks like a hideous storm for the south. Up to 20′ of storm surge flooding in parts of Florida, high risk for serious flash flooding inland, and destructive winds as far north as Atlanta. New NHC forecast brings it to a Category 4 before landfall.

    1. Captain – that is an outstanding find! Thank you for sharing. The bridge looks much different. One of my favorite hurricane books is Sudden Sea by R.A, Scott an excellent non-fiction on the storm. I highly recommend it. I track all of these storms on my hurricane and chart and it’s hard to imagine one coming right at us…but one day it will happen. For this year though the Gulf “wins” with this being the 6th to hit Gulf of Mexico coastline with Ernesto being the only one to hit Atlantic side after hitting Gulf.

      1. Is your chart online or paper? I believe I’ve asked before and apologize because I can’t recall your answer

  43. I have several good friends that live in that area of Florida thats about to get crushed by this hurricane. Its a very nice area of Florida, It has some of the biggest seagrass habitats also in the Gulf that will be getting ripped up just as the non-native tropical seagrass has now made it to Florida. Its going to be interesting from an ecological aspect how far north this Indian and Red sea seagrass can get into the Gulf. It takes advantage of storm activity. For example prior to 2017 hurricanes Brewers Bay with filled with native seagrass about 6 months later it was all Halophila stipulacea.

  44. Seeing a lot of posts that Helene’s rapid intensification is because of warm water. Well, yes, that’s 1/3 of the reason. The water temps are 1-3F above normal there, but even if they were running slightly below normal, with ideal upper level divergence and no wind shear, rapid intensification would still occur. Water temperatures are over-stated in hurricane development. Yes, they are important, but by default they are extremely likely to be over 80 in the GOM at this time of year anyway. Again, statements based on science should include ALL of the information. ALL of the reasons. ALL the time.

    1. What I am seeing which is somewhat different is the speed that the storm is travelling at. It is moving along quickly or at least I think it is.

      1. Forward speed is a little faster than the typical speed of such a system, but nothing way out of the ordinary either. We’ve seen other systems do it down there.

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