• STRMDISC: Tropical Storm Hanna Discussion Number 4

    From COD Weather Processor @1:2320/107 to All on Tue Sep 29 08:39:52 2026
    882
    WTNT43 KNHC 290839
    TCDAT3

    Tropical Storm Hanna Discussion Number 4
    NWS National Hurricane Center Miami FL AL082026
    500 AM AST Tue Sep 29 2026

    Satellite imagery shows Hanna's convective structure has not changed
    much and still displays an exposed low-level center due to strong
    westerly vertical wind shear. The deepest convection remains
    displaced east of the tropical storm's center. A 0225 UTC OSCAT
    scatterometer pass revealed an asymmetric wind field. The latest
    TAFB Dvorak fix was T2.0/30 kt, slightly below objective estimates
    ranging between 34 and 43 kt. Based on a blend of these data, the
    initial intensity is held at 40 kt.

    The initial motion continues east-southeastward at 105/13 kt. Hanna
    is embedded in the flow between a longwave trough to its northeast
    and a larger subtropical ridge to its south. This synoptic pattern
    should result in a continued east-southeastward motion over the next
    24 h or so, with a gradual slowdown in forward speed as the
    mid-latitude trough leaves Hanna behind. Much of the track guidance
    then shows a slightly quicker east-northeastward motion after the
    cyclone becomes vertically shallow and influenced by a low-level
    ridge centered south of the Azores. The updated NHC track forecast
    was largely unchanged from the previous advisory, roughly in between
    the simple (TVCN) and corrected consensus (HCCA) aids.

    Tropical Storm Hanna is forecast to persist in a moisture-starved
    environment, with moderate to strong vertical wind shear prevailing
    over the next 48 to 72 h. However, some near-term fluctuations in
    intensity are possible during this period as intermittent bursts of
    deep convection well east of the center may allow for slight
    intensification. Thereafter, Hanna is expected to be devoid of deep
    convection around the 60 h mark, degenerating into a post-tropical
    cyclone at that time.


    FORECAST POSITIONS AND MAX WINDS

    INIT 29/0900Z 35.2N 46.2W 40 KT 45 MPH
    12H 29/1800Z 34.4N 44.6W 45 KT 50 MPH
    24H 30/0600Z 33.9N 43.5W 40 KT 45 MPH
    36H 30/1800Z 34.2N 42.4W 40 KT 45 MPH
    48H 01/0600Z 34.9N 40.5W 35 KT 40 MPH
    60H 01/1800Z 35.8N 38.3W 30 KT 35 MPH...POST-TROP/REMNT LOW
    72H 02/0600Z 37.0N 35.9W 30 KT 35 MPH...POST-TROP/REMNT LOW
    96H 03/0600Z...DISSIPATED

    $$
    Forecaster Pierce/Pasch


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