• DAY2SVR 3/5 Risk Area Posted

    From Mike Powell@618:250/6 to All on Thu Apr 2 08:38:16 2026
    SWODY2
    SPC AC 020604

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0104 AM CDT Thu Apr 02 2026

    Valid 031200Z - 041200Z

    ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN
    IOWA INTO NORTHERN MISSOURI...

    ...SUMMARY...
    An extensive squall line may develop across parts of the east
    central Great Plains late Friday afternoon, and perhaps become
    capable of producing widespread strong to severe wind gusts and a
    risk for tornadoes while advancing toward to the middle Mississippi
    Valley and southeastern Great Plains through Friday evening.

    ...Synopsis...
    Early-morning water-vapor imagery depicts an upper wave approaching
    the Pacific Northwest. This feature is forecast to translate
    east/southeastward over the next 48 hours, eventually ejecting into
    the central Plains late Friday afternoon into Friday evening. As
    this occurs, robust cyclogenesis is expected along a residual
    baroclinic zone across the southern to central Plains. Low to mid
    60s dewpoints will spread north from the southern Plains/Ozark
    Plateau into the Midwest as the baroclinic zone lifts northward as a
    warm front. By late afternoon a cold front will begin pushing
    southeast across NE, KS, and OK, which will support scattered to
    widespread thunderstorm development by early evening. Elsewhere,
    more isolated thunderstorms are expected along the warm frontal zone
    draped from the Midwest into the upper OH Valley.

    ....Iowa and northern Missouri...

    Regionally, the best convective environment will most likely emerge
    immediately south of the warm front and ahead of the developing
    surface low. Here, seasonally rich low-level moisture coupled with
    several hours of synoptic-scale ascent/cooling aloft will support
    MLCAPE values upwards of 2000 J/kg, and deep-layer shear magnitudes
    should be maximized within the warm sector given closer proximity to
    the upper jet. Latest ensemble guidance continues to show a
    favorable tornado environment along the northern fringe of the warm
    sector, characterized by effective SRH values on the order of
    200-250 m2/s2 and STP values likely increasing into the 2-4 range by
    early evening.

    This environment will likely support a threat for significant
    tornadoes given discrete storm modes; however, guidance continues to
    suggest that initially discrete cells developing along the cold
    front will likely grow upscale within a few hours. CAM solutions
    continue to vary regarding the possibility of pre-frontal supercell
    development along the warm front and/or within the warm sector.
    Limited confidence in a prolonged supercell tornado threat precludes
    higher tornado probabilities at this time, though the strongly
    sheared low-level wind profile will likely support an embedded
    tornado threat within the line to the south of the warm front. If
    pre-frontal supercells can develop along/near the surface warm front
    (as hinted by recent ARW and RRFS solutions) they will likely pose a
    threat for strong tornadoes. As the convective line matures and
    spreads east, severe gusts should become more prevalent, including
    the potential for a significant wind gust or two given the focused
    low-level mass response in close proximity to the surface low.

    ...Kansas into Oklahoma and northern Texas...

    Scattered to widespread thunderstorm development is anticipated by
    late afternoon along the trailing cold front from eastern KS into
    northern OK. Wind vectors through much of the profile will promote
    storm motion and orientation along the initiating cold front, which
    will result in quick upscale growth into a convective line.
    Propagation southeastward into the warm sector may be modulated by
    the mean southwesterly flow regime, though the line should
    eventually move east/southeast through late evening and overnight as
    the cold front advances southeast. While severe hail may be an
    initial threat as convection develops, strong to severe wind gusts
    should quickly become the predominant hazard with some threat for
    embedded circulations.

    Further southwest into southwest OK/northwest TX, weaker forcing for
    ascent will likely yield more sparse storm coverage but a higher
    probability for discrete cells. Forecast hodographs depict marginal
    low-level wind shear, but favorably elongated wind profiles aloft
    that will favor splitting supercells capable of producing large to
    very large (2+ inch) hail. There is also a signal in some guidance
    for somewhat more scattered, potentially elevated, convection
    developing by early afternoon across northwest to north-central TX
    within a weak warm advection regime. While confidence in how
    widespread or intense this activity will be is limited due to model
    variance, the environment should support organized cells capable of
    large hail.

    ...Ohio Valley...

    Ascent along the residual boundary should promote isolated
    thunderstorm by late afternoon as diurnal heating erodes inhibition.
    While deep-layer flow will be more modest compared to locations
    further west, 30-35 knot mid-level winds will help support a few
    organized cells capable of large hail and damaging gusts.

    ..Moore.. 04/02/2026

    $$
    --- MultiMail/DOS
    * Origin: Project Scorpio TEST (618:250/6)