• STRMDISC: Hurricane Isaias Discussion Number 11

    From COD Weather Processor @1:2320/107 to All on Fri Oct 9 18:40:12 2026
    135
    WTNT44 KNHC 090858
    TCDAT4

    Hurricane Isaias Discussion Number 11
    NWS National Hurricane Center Miami FL AL092026
    400 AM CDT Fri Oct 09 2026

    Isaias has intensified overnight. NOAA and Air Force Reserve
    Hurricane Hunter data showed that the maximum flight-level winds
    have increased up to 107 kt, with a better-defined eye and a
    shrinking eyewall. These changes are also present on satellite
    imagery, with a more symmetric presentation along with a warming
    eye/cooling eyewall. The available data suggest a current intensity
    of 95 kt for this advisory.

    Isaias will likely become a major hurricane soon with the improving
    satellite imagery, and it could continue to intensify for the next
    12 hours or so while it moves over very warm and deep water.
    However, a large increase in shear is anticipated before landfall,
    which will probably cause some weakening to occur. This is a tenuous
    spot because it would only take about a 6h delay in the onset of the
    shear to bring a stronger hurricane than expected onshore. The new
    forecast explicitly is a bit higher than the last one, but our best
    forecast at this time is for a high-end category 2 intensity at
    landfall, which is about the same as before. Regardless of its
    exact wind speed at landfall, Isaias will be a dangerous hurricane
    with significant storm surge, damaging winds, and flooding rains.
    The wind field is also predicted to grow due to a trough
    interaction, and some of these impacts will extend well away from
    the center. After landfall, gusty winds are expected to reach well
    inland over portions of the southeastern United States.

    Isaias has turned towards the north-northeast (020/13 kt), and
    the hurricane is expected to turn northward and accelerate later
    today due to increasing flow between an upper trough near the
    northwestern Gulf Coast and a subtropical ridge extending across
    the western Atlantic. Landfall is expected to occur within the
    hurricane warning area Friday night or early Saturday. The new
    forecast is almost the same as before, very near the Google DeepMind
    guidance, which has been very accurate for Isaias.

    Key Messages:

    1. A life-threatening storm surge is expected from the Mouth of the
    Mississippi River to Suwannee, Florida. Residents in the warning
    area should follow advice given by local officials and evacuate
    immediately if told to do so.

    2. Damaging hurricane force-winds are expected over portions of the
    Florida Panhandle, southern Alabama, and southern Mississippi where
    a Hurricane Warning is in effect. Residents in these areas should
    prepare for the possibility of long-duration power outages.

    3. Damaging wind gusts are possible over much of central and
    northern Alabama, extreme eastern Mississippi, and portions of
    western and northern Georgia, especially in areas of higher terrain.
    Additional Tropical Storm and High Wind Watches and Warnings may be
    required for portions of that area later today. Residents should
    secure loose outdoor items, avoid driving high-profile vehicles,
    and prepare for power outages.

    4. Isaias will bring areas of heavy rainfall to the central U.S.
    Gulf coast and much of the Southeast through the weekend.
    Considerable flash and urban flooding, along with significant river
    flooding, will be possible.


    FORECAST POSITIONS AND MAX WINDS

    INIT 09/0900Z 26.4N 88.0W 95 KT 110 MPH
    12H 09/1800Z 28.4N 87.3W 105 KT 120 MPH
    24H 10/0600Z 31.0N 87.1W 65 KT 75 MPH...INLAND
    36H 10/1800Z 33.5N 87.5W 35 KT 40 MPH...POST-TROP/INLAND
    48H 11/0600Z 35.5N 86.7W 25 KT 30 MPH...POST-TROP/INLAND
    60H 11/1800Z 38.2N 83.1W 15 KT 15 MPH...POST-TROP/INLAND
    72H 12/0600Z...DISSIPATED

    $$
    Forecaster Blake


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    --- scorpsmtpd
    * Origin: capitolcityonline.net * KY, USA (1:2320/107)