SPC Mar 27, 2025 1630 UTC Day 1 Convective Outlook

SPC 1630Z Day 1 Outlook

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1128 AM CDT Thu Mar 27 2025

Valid 271630Z - 281200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR THE LOWER
MISSOURI VALLEY...

...SUMMARY...
Isolated to scattered large hail and localized severe wind gusts are
possible across parts of the Lower Missouri/Mid-Mississippi Valleys.

...Central Plains to Lower Missouri/Middle Mississippi Valleys...
Scattered thunderstorms, including a few lingering strong storms,
continue late this morning from eastern KS into northern MO within a
warm-air advection regime.  Morning raob data over the central Great
Plains indicated the northeastern periphery of the EML is located
over the lower MO Valley.  Strong heating in wake of the early day
convection will result in moderate buoyancy developing into
northeastern KS later this afternoon.  Models show a flattening mid-
to upper-level ridge through tonight.  Nebulous/weak forcing at best
is expected in the vicinity of a warm front/outflow intersection
later this afternoon.  However, the erosion of CINH may enable a few
isolated thunderstorms to develop late this afternoon into the
evening.  Recent HRRR runs and the 12 UTC model-run members of the
HREF show a dearth of storm development.  Confidence in appreciable
storm coverage is lowering for diurnally based storm initiation and
casting uncertainty in terms of the potential severe threat. 
Nonetheless, supercellular development could occur in the presence
of moderate instability and favorable wind profiles featuring around
35-40 kt effective shear magnitudes.  A greater coverage of elevated
storms may occur tonight as the low-level jet reestablishes and
storms expand eastward regionally. Large hail is the most probable
hazard in both regimes.

...South Texas...
Visible-satellite imagery shows an extensive cloud shield and
convective cloud debris across much of south TX into the upper
coast, and farther west into the Big Bend region.  This is in
response to a slow-moving upper trough which is forecast to move
across northern Mexico toward Deep South Texas by Friday morning. 
This episodic convection across northern Mexico into adjacent
portions of TX should limit heating during the day.  Forecast
soundings show seasonably moist profiles from the surface through
the mid levels subduing lapse rate magnitudes.  Mid-level flow will
translate through the base of the trough, south of the international
border into the lower Valley of Texas by early evening.  However,
considerably weaker flow with north extent (i.e., Edwards Plateau)
and uncertainty regarding destabilization farther north cast
uncertainty on storm intensity across south-central TX.  The
low-level jet will remain focused across south Texas aiding in
regenerative storm development and an occasional isolated severe
threat may occur with the stronger storms.

..Smith/Jewell.. 03/27/2025

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