820
ACUS48 KWNS 130902
SWOD48
SPC AC 130900
DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0400 AM CDT THU AUG 13 2026
VALID 161200Z - 211200Z
..DISCUSSION
..D4/SUNDAY
STRONG TO POTENTIALLY SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP
IN ASSOCIATION WITH A COLD FRONT THAT WILL ACROSS PARTS OF THE
MIDWEST, OHIO VALLEY, AND NORTHERN MID-ATLANTIC ON SUNDAY.
DEEP-LAYER SHEAR IS GENERALLY FORECAST TO REMAIN WEAK, BUT MODERATE
UNIDIRECTIONAL WESTERLY FLOW (POTENTIALLY 30-40 KT IN THE 850-500 MB
LAYER) WITHIN A FAVORABLY MOIST AND UNSTABLE ENVIRONMENT WILL
SUPPORT POTENTIAL FOR MULTIPLE STORM CLUSTERS WITH WIND-DAMAGE
POTENTIAL.
UNCERTAINTY REMAINS REGARDING FRONTAL TIMING AND THE INFLUENCE (IF
ANY) OF MCVS EMANATING FROM THE PLAINS AND MIDWEST. ALSO, GIVEN THE
GENERALLY WEAK DEEP-LAYER SHEAR, THE MAGNITUDE OF THE SEVERE THREAT
WILL BE STRONGLY INFLUENCED BY THE EXTENT OF PRE-CONVECTIVE HEATING
AND STEEPENING OF LOW-LEVEL LAPSE RATES. CONFIDENCE IS TOO LOW TO
ADD A 15% AREA AT THIS TIME, THOUGH SEVERE PROBABILITIES WILL LIKELY
BE NEEDED LATER IN THE OUTLOOK CYCLE.
..D5/MONDAY
THE FRONT WILL MOVE SOUTHEASTWARD ON MONDAY INTO PARTS OF THE
MID-MS/LOWER OHIO VALLEYS AND MID-ATLANTIC/CAROLINAS. SCATTERED
STORMS ARE AGAIN EXPECTED ALONG/AHEAD OF THE FRONT. SOME WEAKENING
OF LOW/MIDLEVEL FLOW IS EXPECTED AND DEEP-LAYER SHEAR WILL REMAIN
MODEST AT BEST, SO THE SEVERE THREAT MAY REMAIN RATHER ISOLATED.
FARTHER WEST, INCREASING MOISTURE AND INSTABILITY WITHIN A MODEST
WEST-NORTHWESTERLY FLOW REGIME COULD RESULT IN SOME SEVERE-STORM
POTENTIAL FROM THE CENTRAL HIGH PLAINS INTO THE DAKOTAS.
..D6/TUESDAY - D8/THURSDAY
PREDICTABILITY REGARDING THE UPPER-LEVEL PATTERN BEGINS TO WANE BY
EARLY/MID NEXT WEEK. IN GENERAL, PERIODIC BOUTS OF SEVERE STORMS MAY
CONTINUE ACROSS PARTS OF THE CENTRAL/NORTHERN PLAINS AND UPPER
MIDWEST, ALONG THE PERIPHERY OF A PERSISTENT UPPER RIDGE. A
LESS-ORGANIZED SEVERE THREAT MAY ALSO PERSIST NEAR THE REMNANT
FRONTAL ZONE ACROSS PARTS OF THE SOUTHEAST/CAROLINAS.
..DEAN.. 08/13/2026
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