330
ACUS01 KWNS 011951
SWODY1
SPC AC 011949
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0249 PM CDT THU OCT 01 2026
VALID 012000Z - 021200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
SOUTHERN KANSAS/NORTHERN OKLAHOMA...
..SUMMARY
LOCALLY STRONG/GUSTY WINDS AND PERHAPS A BRIEF TORNADO OR TWO MAY
OCCUR THIS AFTERNOON/EARLY EVENING ACROSS PARTS OF SOUTHERN KANSAS
INTO NORTHWEST OKLAHOMA AND VICINITY.
..20Z UPDATE
SOME TRIMMING WAS DONE TO THE NORTHWESTERN EDGE OF THE EXISTING
LEVEL 1/MARGINAL RISK AREA ACROSS SOUTHERN KANSAS WHERE SEVERE
PROBABILITIES HAVE DECREASED IN THE WAKE OF ONGOING CONVECTION. SEE
MCD #2345 FOR ADDITIONAL SHORT-TERM DETAILS.
ELSEWHERE, CONVECTIVE COVERAGE HAS GRADUALLY INCREASED OVER THE PAST
HOUR ACROSS PORTIONS OF SOUTH-CENTRAL/SOUTH TEXAS AMID HOT AND HUMID
CONDITIONS. A LOCALIZED STRONG GUST MAY OCCUR WITH THE STRONGEST
DOWNDRAFTS, BUT POOR MID-LEVEL LAPSE RATES AND WEAKENING DEEP-LAYER
FLOW/SHEAR WILL LIMIT OVERALL CONVECTIVE INTENSITY AND PRECLUDE A
BROADER SEVERE RISK.
RECENT HRRR/RRFS TLE DATA ALSO SUGGEST A LOW PROBABILITY SCENARIO
FOR AN ISOLATED STRONGER STORM TO DEVELOP ALONG THE SURFACE FRONTAL
BOUNDARY ACROSS NORTHEASTERN MISSOURI/WESTERN ILLINOIS LATER THIS
AFTERNOON/EVENING. POOR MID-LEVEL LAPSE RATES AND LIMITED AVAILABLE
BUOYANCY CONTINUE TO SUGGEST THAT THE SEVERITY OF ANY STORM THAT CAN
DEVELOP IS LIKELY TO REMAIN MUTED, HOWEVER.
..CHALMERS/THORNTON.. 10/01/2026
PREV DISCUSSION
/ISSUED 1128 AM CDT THU OCT 01 2026/
..SOUTHERN KANSAS/NORTHERN OKLAHOMA
RECENT SURFACE ANALYSIS SHOWS A WEAK LOW OVER NORTHWEST OK/THE
NORTHEAST TX PANHANDLE, WITH A FRONT EXTENDING NORTHEASTWARD FROM
THIS LOW ACROSS KS. A PACIFIC COLD FRONT ALSO EXTENDS SOUTHWARD FROM
THIS LOW OVER THE SOUTHERN PLAINS. CLOUD COVER REMAINS PREVALENT
OVER THE WARM SECTOR ACROSS THE SOUTHERN/CENTRAL PLAINS LATE THIS
MORNING, AIDED BY LIFT ASSOCIATED WITH A MID/UPPER-LEVEL TROUGH/LOW
CENTERED OVER THE SOUTHWEST KS AND THE OK/TX PANHANDLES PER LATEST
WATER VAPOR SATELLITE IMAGERY. WHILE NOT A CLASSIC SETUP FOR
NON-SUPERCELL TORNADOES GIVEN MODEST LOW-LEVEL LAPSE RATES AND A
PROGRESSIVE COLD FRONT, THERE MAY STILL BE A WINDOW FOR A BRIEF
TORNADO OR TWO THIS AFTERNOON/EARLY EVENING ACROSS PARTS OF SOUTHERN
KS INTO NORTHWEST OK AND VICINITY.
THIS AREA SHOULD GENERALLY WARM INTO THE 70S PER RECENT RAP/HRRR
GUIDANCE, AND EVEN MODEST BREAKS IN THE CLOUD COVER SHOULD SUPPORT
SOME STEEPENING OF LOW-LEVEL LAPSE RATES IN AN OTHERWISE
VORTICITY-RICH ENVIRONMENT ALONG/NEAR BOTH FRONTS. CURRENT
EXPECTATIONS ARE FOR CELLS TO DEVELOP OVER SOUTHWEST KS/NORTHWEST OK
IN THE NEXT COUPLE OF HOURS (BY 18-20Z), WITH COOL TEMPERATURES
ALOFT (AROUND -10 TO -11 C AT 500 MB) AIDING UPDRAFT STRENGTH IN AN
OTHERWISE WEAK DEEP-LAYER SHEAR ENVIRONMENT. SMALL HAIL, STRONG TO
LOCALLY SEVERE WINDS, AND PERHAPS A BRIEF TORNADO COULD OCCUR WITH
THIS ACTIVITY UNTIL THE SOUTHEASTWARD-ADVANCING COLD FRONT UNDERCUTS
CONVECTION BY LATE AFTERNOON/EARLY EVENING.
..TEXAS/ARKLATEX INTO THE MID MISSISSIPPI VALLEY/MIDWEST
ONGOING CONVECTION ACROSS CENTRAL/NORTH-CENTRAL TX HAS REMAINED
SUB-SEVERE THROUGH THE MORNING. A RATHER MOIST LOW-LEVEL AIRMASS
CHARACTERIZED BY GENERALLY MID TO UPPER 70S SURFACE DEWPOINTS IS
PRESENT ACROSS EAST/COASTAL TX AHEAD OF THESE THUNDERSTORMS. WHILE
LAPSE RATES ALOFT WILL REMAIN POOR (REFERENCE 12Z OBSERVED SOUNDINGS
FROM FWD/DRT), SOME INCREASE IN INSTABILITY IS ANTICIPATED
DOWNSTREAM THIS AFTERNOON WITH CONTINUED DAYTIME HEATING.
SOUTH-SOUTHWESTERLY LOW/MID-LEVEL FLOW WILL CONTINUE TO GRADUALLY
DIMINISH THROUGH THE DAY AS THE PRIMARY MID/UPPER-LEVEL TROUGH
EJECTS NORTHEASTWARD ACROSS THE SOUTHERN/CENTRAL PLAINS THROUGH THIS
EVENING. THIS WILL LIMIT THE DEGREE OF DEEP-LAYER SHEAR AVAILABLE TO
SUPPORT ORGANIZED UPDRAFTS AND OVERALL SEVERE POTENTIAL ACROSS THE
ARKLATEX INTO EAST/SOUTH TX. THAT SAID, GUSTY WINDS MAY STILL OCCUR
ON A LOCALIZED BASIS AS CONVECTION SPREADS EASTWARD ACROSS THESE
AREAS THROUGH THE AFTERNOON/EVENING.
MODESTLY ENHANCED MID-LEVEL FLOW AND GREATER DEEP-LAYER SHEAR WILL
BE PRESENT THIS AFTERNOON FARTHER NORTH INTO THE MID MS
VALLEY/MIDWEST, AS MULTIPLE SUBTLE MID-LEVEL VORTICITY MAXIMA SPREAD
NORTHEASTWARD OVER THESE REGIONS. HOWEVER, BOTH BOUNDARY-LAYER
INSTABILITY AND LAPSE RATES ALOFT ARE FORECAST TO REMAIN RATHER
WEAK, WHICH SHOULD LIMIT UPDRAFT STRENGTH AND OVERALL SEVERE
POTENTIAL WITH NORTHWARD EXTENT ACROSS THESE AREAS.
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