• STRMDISC: Tropical Depression Two Discussion Number 4

    From COD Weather Processor @1:2320/107 to All on Mon Jul 20 08:50:16 2026
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    WTNT42 KNHC 200850
    TCDAT2

    Tropical Depression Two Discussion Number 4
    NWS National Hurricane Center Miami FL AL022026
    400 AM CDT Mon Jul 20 2026

    The tropical depression continues to have a fairly unimpressive
    appearance on satellite imagery, with just a few fragments of deep
    convection around the circulation center. An Air Force Reserve
    reconnaissance aircraft has been sampling the system this morning,
    finding that the pressure continues to gradually decrease with a
    peak 925 mb flight level wind of 38 kt. This data is the primary
    justification for increasing the winds slightly to 30 kt for this
    advisory.

    Recon fixes indicate that the depression is now moving slowly
    northwestward at 320/3 kt. The tropical cyclone remains sandwiched
    between two mid-level ridges, one to its northwest centered over the
    Rockies and one to its southeast centered near the Bahamas. Over
    time, the ridge over the Rockies is expected to become the dominant
    steering feature as a longwave trough moves into the northeastern
    United States. The byproduct of this change is that the system
    should begin to gradually turn more west-northwestward and westward
    by the middle of this week. This track should bring the cyclone near
    or along the Gulf coast, approaching the mouth of the Mississippi
    River by 72 h. The track guidance this cycle has shifted a
    little northward over these first few days, and the NHC track
    forecast was also shifted in that direction, blending the simple
    consensus aid TVCN with the Google DeepMind (GDMI) track guidance.

    As mentioned previously, the depression's broad structure and
    mid-level dry air are keeping the convection limited. Thus, its intensification continues to be gradual. The depression is forecast
    to become a tropical storm later today and continue to slowly
    intensify while the shear remains low to moderate. After 36 h,
    northeasterly shear is expected to increase markedly, and the
    guidance is coming into better agreement that this should halt
    additional intensification after that time. With the northward shift
    in the track, the tropical cyclone is more likely to be disrupted by
    land interaction beyond 60 h, and the latest NHC intensity forecast
    now shows gradual weakening afterwards. This intensity forecast
    still remains sensitive to the ultimate track, though it is notable
    that the latest Google DeepMind ensemble mean only tracks the
    cyclone out to 72 h, suggesting the majority of its members
    dissipate the system beyond that period. The NHC intensity forecast
    is a little lower than the previous cycle after 72 h, but it
    wouldn't be surprising if future adjustments are needed if more
    guidance trends towards a further inland solution.


    Key Messages:

    1. The depression is expected to gradually strengthen and could
    bring tropical storm conditions to portions of the Florida Panhandle
    and Alabama coast beginning tonight into Tuesday, where a Tropical
    Storm Watch is in effect.

    2. Interests in Mississippi, Louisiana, and Texas should monitor the
    progress of this system, as additional watches could be required for
    portions of that area over the next day or two.

    3. Areas of flash flooding will be possible through Friday along the
    Gulf Coast and adjacent inland locations from western Florida to the
    Middle Texas Coast, including southern portions of Alabama,
    Mississippi, and Louisiana.


    FORECAST POSITIONS AND MAX WINDS

    INIT 20/0900Z 28.5N 85.4W 30 KT 35 MPH
    12H 20/1800Z 28.7N 85.8W 35 KT 40 MPH
    24H 21/0600Z 29.0N 86.3W 40 KT 45 MPH
    36H 21/1800Z 29.3N 86.9W 45 KT 50 MPH
    48H 22/0600Z 29.6N 87.8W 45 KT 50 MPH
    60H 22/1800Z 29.8N 89.1W 45 KT 50 MPH
    72H 23/0600Z 29.7N 90.9W 40 KT 45 MPH...INLAND
    96H 24/0600Z 29.6N 93.0W 35 KT 40 MPH...INLAND
    120H 25/0600Z 29.5N 95.6W 30 KT 35 MPH...INLAND

    $$
    Forecaster Papin


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