SPC AC 010538

   Day 1 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1238 AM CDT Tue Apr 01 2025

   Valid 011200Z - 021200Z

   ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATE THIS
   EVENING ACROSS PARTS OF NORTH CENTRAL OKLAHOMA INTO SOUTH CENTRAL
   KANSAS...

   ...SUMMARY...
   Rapid, intense thunderstorm development is possible this evening
   across parts of the central and southern Great Plains.  A few
   supercells posing a risk for large hail and a couple of strong
   tornadoes are possible, particularly across parts of north central
   Oklahoma into south central Kansas.

   ...Discussion...
   Amplification of mid/upper flow across the southern mid-latitudes of
   the eastern Pacific into western North America appears underway,
   with a seasonably strong cyclonic jet now digging inland of the
   central/southern California coast.  An initially significant
   mid-level low within the large-scale troughing to the north of this
   feature appears to be in the process of devolving into at least a
   couple of significant short wave perturbations as it progresses
   inland of the northern Pacific coast.  

   Models indicate that the lead perturbation will progress across the
   Rockies into the Great Plains today through tonight, and contribute
   to significant lower/mid-tropospheric cyclogenesis over the north
   central Great Plains through middle Missouri Valley by 12Z
   Wednesday.  A notable trailing perturbation is forecast to dig
   inland of the Pacific coast, near and west of the Sierra Nevada.

   Given the forecast synoptic pattern evolution, and intensifying
   lower/mid tropospheric wind fields (including 50-70+ kt southerly
   around 850 mb and 90-100+ kt southwesterly) across the south central
   Great Plains into lower Missouri Valley late this evening through
   early Wednesday, the environment would seem at least conditionally
   supportive of an outbreak of severe thunderstorms.  However,
   low-level moisture return, in the wake of a still ongoing intrusion
   of cool/dry air to the east of the Rockies, remains a source of
   uncertainty, and a potentially limiting factor, concerning the risk
   for severe thunderstorms today through tonight.

   ...Great Plains into portions of the Upper Midwest...
   An initial narrow plume of low-level moisture return appears
   underway up the Rio Grande Valley toward the Texas South Plains. 
   However, models continue to indicate that boundary-layer moistening,
   characterized by lower/mid 60s surface dew points, may not begin
   advecting to the north of the Red River until late afternoon.  Even
   so, there appears potential for this moisture to rapidly advect
   northward, within deepening surface troughing, across parts of
   western and central Oklahoma into central Kansas through late
   evening.

   In the presence of steep lapse rates, it appears that there may be
   sufficient destabilization to support the initiation of widely
   scattered thunderstorm development near the sharpening dryline, from
   parts of west central Kansas into the Texas Edwards Plateau vicinity
   by late afternoon.  Strongest storms probably will be focused across
   parts of southwestern Oklahoma into portions of the Texas South
   Plains, where the environment may become conducive to the evolution
   of supercells, though substantial mid-level inhibition may tend to
   limit eastward propagation away from the dryline.

   The most significant convective development still seems most
   probable during the mid to late evening, in association with the
   better low-level moisture return and destabilization, which is
   forecast to coincide with the substantive intensification of the
   wind fields in the 850-500 mb layer across the Texas/Oklahoma
   Panhandle vicinity through southern Kansas/northern Oklahoma.  This
   may focus near/east-northeast of a developing triple point low,
   generally forecast to track by a number of models across
   northwestern Oklahoma through south central Kansas during the
   02/03-06Z time frame.

   Although the extent of upscale convective growth across this region
   remains unclear, the environment appears conducive at least to the
   evolution of several discrete supercells.  These may be accompanied
   by large hail initially, and increasing tornadic potential in the
   presence of enlarging low-level hodographs and a moistening boundary
   layer across and northeast of the I-35 corridor.

   It is possible that elevated moisture return and destabilization
   could be sufficient to support a risk for thunderstorms capable of
   producing severe hail as far northeast as portions of the Upper
   Midwest by late tonight. 

   ...Interior Valley of central California...
   Beneath cold air and an associated cyclonic vorticity center
   forecast to overspread the region late this afternoon, it appears
   that the environment could become conducive to an isolated strong
   storm or two, which gust pose a risk for small hail, gusty winds and
   perhaps a brief tornado or two.

   ..Kerr/Weinman.. 04/01/2025

   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z