• STRMDISC: Hurricane Erin Discussion Number 33

    From COD Weather Processor@1:2320/105 to wx-atlan@lists.illinois.edu on Tuesday, August 19, 2025 14:57:21
    980
    WTNT45 KNHC 191457
    TCDAT5

    Hurricane Erin Discussion Number 33
    NWS National Hurricane Center Miami FL AL052025
    1100 AM EDT Tue Aug 19 2025

    Erin's cloud pattern continues to be disrupted by vertical wind
    shear, with the low-level center situated near the northwestern edge
    of the main area of deep convection. There are still well-defined
    convective banding features over the eastern semicircle of the
    system. Reports from an Air Force Hurricane Hunter aircraft
    indicate that the central pressure has risen compared to earlier
    this morning. The advisory intensity is set to 90 kt, comparable to
    a Dvorak Current Intensity number from TAFB. However, wind
    observations from the Hurricane Hunters suggest that this intensity
    estimate may be on the high side.

    The hurricane is moving a little faster to the northwest with an
    initial motion estimate of 325/8 kt. Erin is expected to turn
    northward around the western periphery of a subtropical anticyclone
    centered southeast of Bermuda. Later in the period, the system
    should turn to the northeast with some increase in forward speed as
    it moves into the mid-latitude westerlies. There are no
    significant adjustments to the previous NHC forecast track and the
    official forecast lies very close to the latest dynamical model
    consensus, TVCA.

    Predicting Erin's intensity is somewhat problematic. Given the
    current disorganization of the cloud pattern, one would be reluctant
    to call for restrengthening. However,the dynamical guidance shows
    increasingly anticyclonic upper-level flow over the system and the
    SHIPS model diagnoses a significant decrease in vertical wind shear.
    Therefore, the official forecast shows a bit of restrengthening in
    the next 36 hours. This is somewhat above the model consensus but
    below the latest statistical/dynamical LGEM guidance.

    The global models continue to show an increase in the size of the
    hurricane, with the tropical-storm-force wind radii crossing the
    North Carolina Outer Banks within the next couple of days.
    Accordingly, Tropical Storm and Storm Surge warnings have been
    issued for this area.

    It should be noted that the 34- and 50-kt wind speed probabilities
    beyond 36 hours in the text and graphical products are likely
    underestimating the risk of those winds occurring. This is because
    the forecast wind field of Erin is considerably larger than average
    compared to the wind field used to derive the wind speed probability
    product.

    KEY MESSAGES:

    1. Erin is expected to produce life-threatening surf and rip
    currents along the beaches of the Bahamas, much of the east coast of
    the U.S., Bermuda, and Atlantic Canada during the next several days.
    Beachgoers in those areas should follow advice from lifeguards,
    local authorities, and beach warning flags.

    2. Storm surge flooding and tropical storm conditions are expected
    in the North Carolina Outer Banks beginning late Wednesday or
    Wednesday night, where Tropical Storm and Storm Surge Warnings are
    now in effect. The storm surge will be accompanied by large waves,
    leading to significant beach erosion and overwash, making some roads impassible.

    3. Heavy rainfall from the outer bands of Erin will continue today
    for the Turks and Caicos and through tonight for the Bahamas. Flash
    and urban flooding are possible.

    4. Interests along the U.S. Mid-Atlantic and southern New England
    coasts and on Bermuda should also monitor the progress of Erin as
    strong winds are possible Thursday and Friday.


    FORECAST POSITIONS AND MAX WINDS

    INIT 19/1500Z 25.6N 72.4W 90 KT 105 MPH
    12H 20/0000Z 27.0N 73.1W 90 KT 105 MPH
    24H 20/1200Z 29.1N 73.9W 90 KT 105 MPH
    36H 21/0000Z 31.4N 73.6W 95 KT 110 MPH
    48H 21/1200Z 33.7N 72.4W 95 KT 110 MPH
    60H 22/0000Z 35.6N 70.0W 90 KT 105 MPH
    72H 22/1200Z 37.3N 66.6W 85 KT 100 MPH
    96H 23/1200Z 40.3N 58.7W 65 KT 75 MPH
    120H 24/1200Z 42.8N 50.0W 55 KT 65 MPH...POST-TROP/EXTRATROP

    $$
    Forecaster Pasch


    = = = = = = =
    To unsubscribe from WX-ATLAN and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-ATLAN.

    --- SBBSecho 3.28-Linux
    * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)