384
ACUS01 KWNS 200552
SWODY1
SPC AC 200550
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1250 AM CDT SAT JUN 20 2026
VALID 201200Z - 211200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM EASTERN
COLORADO INTO WESTERN/CENTRAL KANSAS AND SOUTHERN NEBRASKA...
..SUMMARY
SEVERE THUNDERSTORMS ARE LIKELY ACROSS PORTIONS OF THE CENTRAL
PLAINS VICINITY THIS AFTERNOON AND EVENING. LARGE TO VERY LARGE
HAIL, SEVERE WINDS (SOME 75+ MPH), AND TORNADOES ARE POSSIBLE.
..CENTRAL PLAINS
A LOW-AMPLITUDE MID/UPPER-LEVEL SHORTWAVE TROUGH WILL MOVE FROM THE
INTERMOUNTAIN WEST TOWARD THE CENTRAL/NORTHERN HIGH PLAINS THROUGH
THE PERIOD. IN RESPONSE TO THIS SYSTEM, A LEE CYCLONE IS FORECAST TO
DEEPEN ACROSS EASTERN CO. A SURFACE FRONT INITIALLY DRAPED FROM
EASTERN CO INTO KS WILL MOVE NORTHWARD THROUGH THE DAY, WITH ITS
NORTHWARD EXTENT INFLUENCED BY MORNING ELEVATED CONVECTION THAT MAY
PERSIST THROUGH MUCH OF THE DAY ACROSS PARTS OF CENTRAL NE. RICH
LOW-LEVEL MOISTURE WILL RETURN IN TANDEM WITH THE FRONT, WITH
LOW/MID 60S F DEWPOINTS REACHING INTO PARTS OF SOUTHERN NE AND
NORTHEAST CO, AND UPPER 60S TO LOW 70S F DEWPOINTS SPREADING INTO
PARTS OF CENTRAL/SOUTHEAST KS.
RELATIVELY STEEP MIDLEVEL LAPSE RATES SPREADING ATOP THE RETURNING
MOISTURE WILL RESULT IN MODERATE TO STRONG DESTABILIZATION, AS
MLCAPE INCREASES TO NEAR/ABOVE 2000 J/KG ACROSS PARTS OF THE CENTRAL
HIGH PLAINS. SCATTERED THUNDERSTORM DEVELOPMENT IS EXPECTED BY LATE
AFTERNOON FROM SOUTHEAST WY AND THE NE PANHANDLE INTO EASTERN CO,
WITH AT LEAST ISOLATED STORMS POSSIBLE FARTHER EAST, ALONG AND JUST
NORTH OF THE SURFACE FRONT. VEERING WIND PROFILES AND EFFECTIVE
SHEAR OF 40+ KT WILL BE FAVORABLE FOR ORGANIZED STORMS, INCLUDING
SUPERCELLS.
A THREAT FOR LARGE TO VERY LARGE HAIL AND LOCALIZED SEVERE GUSTS
WILL ACCOMPANY INITIAL SUPERCELL DEVELOPMENT. SOME TORNADO THREAT
COULD ALSO EVOLVE, ESPECIALLY WITH ANY SUPERCELLS NEAR THE FRONT
THAT MOVE INTO AN ENVIRONMENT OF RICHER MOISTURE AND STRONGER
LOW-LEVEL SHEAR (ASSOCIATED WITH A MODEST NOCTURNAL LOW-LEVEL JET)
DURING THE EVENING. A TENDENCY TOWARD UPSCALE GROWTH IS EXPECTED
WITH TIME ALONG AND NORTH OF THE SURFACE FRONT, RESULTING IN AN
INCREASING SEVERE-WIND THREAT, WITH GUSTS ABOVE 75 MPH POSSIBLE.
SOME DAMAGING-WIND AND BRIEF-TORNADO THREAT COULD CONTINUE THROUGH
THE END OF THE PERIOD INTO EAST-CENTRAL/SOUTHEAST KS, WHERE MLCINH
WILL REMAIN MINIMAL DUE TO VERY RICH LOW-LEVEL MOISTURE.
ONLY MINOR ADJUSTMENTS HAVE BEEN MADE TO THE ENHANCED RISK, THOUGH
MORE SUBSTANTIAL CHANGES MAY EVENTUALLY BE NEEDED, DEPENDING ON THE
INFLUENCE OF EARLY-DAY CONVECTION ACROSS PARTS OF THE THREAT AREA.
..NORTHERN UT/SOUTHEAST ID INTO WESTERN/CENTRAL WY
AS A MID/UPPER-LEVEL SHORTWAVE TROUGH OVERSPREADS THE REGION DURING
THE AFTERNOON, SCATTERED HIGH-BASED THUNDERSTORM DEVELOPMENT IS
EXPECTED FROM NORTHEAST UT/SOUTHEAST ID INTO WESTERN WY. ISOLATED
DOWNBURSTS WILL BE POSSIBLE WITH INITIAL DEVELOPMENT, AND SOME
OUTFLOW AGGREGATION COULD RESULT IN LOCALIZED STRONG TO SEVERE WIND
SWATHS FROM LATE AFTERNOON INTO EARLY EVENING, AS CONVECTION SPREADS
EASTWARD.
..PARTS OF TX INTO THE SOUTHEAST AND FLORIDA
SCATTERED TO WIDESPREAD CONVECTION IS AGAIN EXPECTED WITHIN A VERY
MOIST (PW NEAR/ABOVE 2 INCHES) ENVIRONMENT FROM CENTRAL/EASTERN TX
INTO PARTS OF THE SOUTHEAST AND FLORIDA. LOCALIZED WET MICROBURSTS
WILL AGAIN BE POSSIBLE, THOUGH DEEP-LAYER SHEAR WILL GENERALLY BE
WEAK. ORGANIZED SEVERE POTENTIAL APPEARS TOO NEBULOUS TO ADD WIND
PROBABILITIES AT THIS TIME. A LEVEL-1/MARGINAL RISK MAY EVENTUALLY
BE NEEDED FOR PARTS OF THE REGION, IF TRENDS SUPPORT ANY MESOSCALE
CORRIDORS OF SOMEWHAT MORE ORGANIZED THREAT.
..WESTERN PA
RELATIVELY LOW-TOPPED CONVECTION MAY DEVELOP ACROSS PARTS OF WESTERN
PA AND VICINITY THIS AFTERNOON, WITHIN A BROAD WEST-NORTHWESTERLY
FLOW REGIME. BUOYANCY WILL REMAIN WEAK, BUT MODESTLY ENHANCED FLOW
AND STEEP LOW-LEVEL LAPSE RATES COULD SUPPORT LOCALIZED STRONG
GUSTS. THE MAGNITUDE OF THE THREAT APPEARS TOO LIMITED FOR WIND
PROBABILITIES AT THIS TIME.
..DEAN/SQUITIERI.. 06/20/2026
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