• Flood Risk AL/FL/GA

    From Mike Powell@618:250/10 to All on Fri Oct 9 14:07:42 2026
    AWUS01 KWNH 091703
    FFGMPD
    FLZ000-GAZ000-ALZ000-092300-

    Mesoscale Precipitation Discussion 1462
    NWS Weather Prediction Center College Park MD
    101 PM EDT Fri Oct 09 2026

    Areas affected...Southern AL...FL Panhandle...Southwest GA

    Concerning...Heavy rainfall...Flash flooding possible

    Valid 091700Z - 092300Z

    SUMMARY...Heavy rainfall associated with Hurricane Isaias will
    continue to lift north over the next several hours across southern
    AL, the FL Panhandle, and southwest GA. The threat for flash
    flooding will gradually increase with time.

    DISCUSSION...The latest GOES-E IR satellite imagery along with
    conventional radar mosaics show the eye of Hurricane Isaias
    continuing its approach to the FL Panhandle. As the storm
    continues to lift north this afternoon, it will be increasingly
    interacting with a frontal zone draped around the north side of
    the storm's circulation.

    Deep and strongly convergent southerly low to mid-level flow
    around the eastern flank of the storm will surge north across the
    FL Panhandle over the next several hours. This will foster an
    expanding shield of heavy rainfall more regionally via deep
    warm/moist air advection and associated isentropic ascent.
    Gradually the poleward transport of instability will favor the
    development and expansion of convection near and north of the
    front in an elevated fashion. However, core instability-driven
    convective bands associated with Isaias will be focusing farther
    south, but will be lifting north around the storm's eastern
    semicircle toward the FL Panhandle.

    A nose of MUCAPE values across the eastern Gulf of America are on
    the order of 1500 to 2500 J/kg in association with the deep layer
    southerly flow, and much of the stronger convective banding will
    be aligned with this instability axis in conjunction with stronger
    low-level convergence. Central convection associated with the core
    of Isaias will likely still remain largely offshore until later
    this afternoon, but rainfall rates are expected to increase ahead
    of this as strong deep layer forcing increases along with outer
    convective banding features.

    Rainfall rates of up to 1 inch/hour can be expected to arrive by
    around 21Z (4PM CDT), with rates potentially reaching 2+
    inches/hour shortly thereafter. These rainfall rates and an
    expected increase in cell-training concerns should support some 3
    to 5+ inch totals by early this evening, and this is consistent
    with the 12Z HREF/REFS guidance.

    FFG are very high across the region, so initially the soils/ground
    conditions should be able to accommodate the front-end rainfall
    ahead Isaias' central convection and impending landfall in the
    western FL Panhandle, but as the rates increase and begin
    involving more urbanized areas, the concerns for flash flooding
    will begin to steadily increase.

    Orrison

    ATTN...WFO...BMX...JAX...MOB...TAE...

    ATTN...RFC...ALR...ORN...NWC...

    LAT...LON 31848541 31658440 31208357 30648326 30168338
    29828371 29578433 29508524 29698574 30038631
    30108706 30188800 30558836 31068821 31528756
    31788659

    $$
    --- MultiMail/DOS
    * Origin: capitolcityonline.net * KY, USA (618:250/10)