622
ACUS01 KWNS 031638
SWODY1
SPC AC 031637

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1137 AM CDT Fri May 03 2024

Valid 031630Z - 041200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR
WEST-CENTRAL TEXAS...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
THE CENTRAL GREAT PLAINS...

...SUMMARY...
Giant hail, a few tornadoes, and severe gusts are possible over
parts of west-central Texas this afternoon and evening.

...Southern Great Plains...
Visible satellite imagery and morning surface analysis shows a very
moist airmass across the Edwards Plateau northward to a residual
effective boundary draped northwest to southeast across the TX South
Plains into central TX.  Near and south of the boundary, low-level
moisture approaching the daily climatological maximum for several
raob sites (reference 12z DRT, BRO, CRP) will contribute to a large
moisture reservoir across west TX by mid-late afternoon.  A
north-south dryline intersecting the differential heating
zone/residual boundary will help focus thunderstorm development
later this afternoon/evening.  Insolation through peak heating will
contribute to very large to extreme buoyancy (3000-4000+ J/kg
MLCAPE) across the Enhanced Risk area.  The nose of a westerly
250-mb speed max (70-90 kt) will move into west TX later this
afternoon/evening acting to elongate hodographs.  Expecting heating
and weak convergence in the vicinity of the aforementioned surface
boundaries to contribute to a weakened cap by mid afternoon.  Widely
scattered to scattered storms are expected to develop through the
early evening according to the latest model guidance.  Large to
giant hail (max size 3-4+ inches in diameter), a few tornadoes, and
severe gusts are possible across the TX South Plains extending
southeastward into portions of the Big Country.  Depending on
storm-scale interactions and local augmentation of the low-level
wind profile, a strong tornado cannot be ruled out, but uncertainty
at these scales precludes a delineated risk area.  Some upscale
growth into a severe cluster is expected across west-central TX this
evening with severe gusts perhaps becoming the primary hazard late.

...Central Plains...
No change in forecast thinking for a large hail/severe gust risk
area across the central Plains.  Though nowhere nearly as moist as
the TX outlook area, a diurnally destabilized plume of moist
advection should support a secondary relative max in severe
potential along/ahead of the cold front and dryline from parts of
eastern CO to western/northern KS and southern NE.  Convection
should develop by mid/late afternoon in a regional convergence
maximum near and northeast of the surface low, with MLCINH weakened
by favorable diurnal heating.  Surface dewpoints in the 40s to low
50s F should be common, with steep surface-500-mb lapse rates,
500-1000 J/kg MLCAPE and well-mixed subcloud layers.
Effective-shear magnitudes around 40-50 kt indicate potential for
organized convection -- both in quasi-linear form near the front and
initially discrete (but later merging upscale) off the dryline.
Though activity will encounter a more-stable boundary layer with
time and eastward extent across KS/NE, at least marginal severe-gust
potential may last overnight as far eastward as parts of the
Missouri Valley region.

..Smith/Barnes/Squitieri.. 05/03/2024

$$