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  • MESO: Mesoscale Discussion 2270

    From COD Weather Processor@1:2320/105 to [email protected] on Thu Dec 25 07:46:59 2025
    ACUS11 KWNS 250746
    SWOMCD
    SPC MCD 250746=20
    CAZ000-251015-

    Mesoscale Discussion 2270
    NWS Storm Prediction Center Norman OK
    0146 AM CST Thu Dec 25 2025

    Areas affected...Parts of the North Coast of California

    Concerning...Severe potential...Watch unlikely=20

    Valid 250746Z - 251015Z

    Probability of Watch Issuance...20 percent

    SUMMARY...The risk for damaging convective gusts and possibly a
    brief tornado is increasing, with the greatest threat expected
    between 09-12Z.

    DISCUSSION...As of 0730Z, radar data from KMUX shows an expansive,
    strongly forced band of stratiform rain with gradually
    deepening/intensifying convective elements. As a robust
    negative-tilt shortwave trough and accompanying jet continue toward
    the coast, this activity will spread east-northeastward into the
    North Coast of California during the 09-12Z time frame. Despite
    limited buoyancy, the strong forcing for ascent and strengthening
    deep-layer flow/shear should favor a modest uptick in convective organization/intensity as it approaches the coast. Given the
    strongly forced nature and 50+ kt flow in the lowest 1 km AGL, the
    primary concern will be damaging wind gusts. However, a brief
    tornado cannot be ruled out, aided by upwards of 200 m2/s2 0-1 km
    SRH and at least neutral boundary-layer static stability along the
    immediate coastal areas.

    ..Weinman/Smith.. 12/25/2025

    ...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!_tjgE6HrSofcYt_vEpX9dA-5izEznpjXmh05FiNx0ZW_vgzlvYghTZQktEjSEx5y_kzBpJM4m= TmMxCkh21UUIldgJRw$ for graphic product...

    ATTN...WFO...STO...MTR...EKA...

    LAT...LON 36862224 37742283 38562351 39312403 39912430 40352457
    40682447 40782431 40702392 40392355 40002312 39372247
    38552192 37162146 36682149 36502170 36432200 36862224=20

    MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH
    MOST PROBABLE PEAK WIND GUST...55-70 MPH


    =3D =3D =3D
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    --- SBBSecho 3.28-Linux
    * Origin: Capitol City Online (1:2320/105)
  • From COD Weather Processor @1:2320/107 to All on Tue Sep 8 19:49:42 2026
    ACUS11 KWNS 081949
    SWOMCD
    SPC MCD 081949
    IAZ000-NEZ000-082145-

    Mesoscale Discussion 2270
    NWS Storm Prediction Center Norman OK
    0249 PM CDT Tue Sep 08 2026

    Areas affected...portions of extreme eastern Nebraska into central
    Iowa

    Concerning...Severe potential...Watch possible

    Valid 081949Z - 082145Z

    Probability of Watch Issuance...60 percent

    SUMMARY...Thunderstorms should gradually increase in coverage and
    intensity as a surface cold front approaches. The strongest storms
    may be accompanied by at least a few severe gusts and perhaps a
    tornado or two. Convective trends are being monitored for the need
    of a WW issuance.

    DISCUSSION...A relatively broad swath of precipitation is currently overspreading central NE into the northern half of IA, ahead of a
    surface cold front, which has limited insolation and boundary-layer destabilization across much of the region thus far. However, ample boundary-layer mixing is underway to the southern periphery of this
    rain band, where surface temperatures have heated into the 90s F (to
    near 100 F in some spots). Given low to mid 70s F surface dewpoints,
    MLCAPE has boosted to over 2000 J/kg despite mediocre mid-level
    lapse rates.

    It is unclear precisely when storms will initiate since much of the
    available deep-layer ascent will glance the region to the north.
    Nonetheless, a pre-frontal trough is gradually drifting east across
    far southeastern NE, and this boundary may serve as a potential
    focusing mechanism for more robust surface based thunderstorm
    development over the next few hours. Storms may initially be
    semi-discrete and anafrontal in nature. As the storms mature, and
    assuming they can propagate into the warm sector, then surface-based
    convection will become possible. These storms would most likely
    become an MCS capable of producing a few severe gusts and perhaps a
    couple of QLCS tornadoes.

    A Severe Thunderstorm Watch may be needed when convective initiation
    and intensification become more apparent.

    ..Squitieri/Hart.. 09/08/2026

    ...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fjg!63bzBlHU7s82QU_b_7ttPiXc9LxDiioiweVTYAoEDoepHDv_Phd29c2GPkCNCCasAyx-lzrB2fTx1BkBSTY61dg2axo$ for graphic product...

    ATTN...WFO...DVN...DMX...OAX...

    LAT...LON 41149681 41829577 42539383 42569145 42379101 41649098
    41089215 40769469 40649550 40599628 41149681

    MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
    MOST PROBABLE PEAK WIND GUST...55-70 MPH
    MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN


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