617
ACUS02 KWNS 020602
SWODY2
SPC AC 020600
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0100 AM CDT THU JUL 02 2026
VALID 031200Z - 041200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE BLACK
HILLS VICINITY INTO PARTS OF THE MIDWEST AND LOWER GREAT LAKES...
..SUMMARY
ISOLATED TO SCATTERED SEVERE STORMS ARE POSSIBLE FROM THE
NORTHERN/CENTRAL PLAINS INTO THE MIDWEST, TENNESSEE VALLEY, AND
MID-ATLANTIC ON FRIDAY.
..SYNOPSIS
UPPER-LEVEL RIDGING WILL BEGIN TO FLATTEN AND SPREAD WESTWARD ON
FRIDAY. MODEST SOUTHWESTERLY FLOW ALOFT WILL CONTINUE ACROSS MUCH OF
THE ROCKIES. IN THE EAST, STRONGER CYCLONIC FLOW ALOFT WILL CONTINUE
IN NEW ENGLAND AND THE NORTHERN MID-ATLANTIC. A SURFACE LOW WILL
DEEPEN IN PARTS OF THE CENTRAL HIGH PLAINS. A
QUASI-STATIONARY/OUTFLOW COMPOSITE BOUNDARY WILL BE SITUATED WITHIN
THE CENTRAL/NORTHERN PLAINS INTO THE LOWER GREAT LAKES REGION.
..BLACK HILLS VICINITY INTO MID-MISSOURI/MISSISSIPPI VALLEYS
FORECAST UNCERTAINTY REMAINS WITH RESPECT TO HOW CONVECTION EVOLVES
THURSDAY NIGHT INTO EARLY FRIDAY MORNING. SOME CONVECTION COULD
LINGER IN PARTS OF SOUTH DAKOTA AND POSSIBLY NEBRASKA. AT THE VERY
LEAST, PORTIONS OF THE CENTRAL/NORTHERN PLAINS WILL BE IMPACTED BY
OUTFLOW FROM EARLIER CONVECTION. THE POSITION OF THE OUTFLOW WILL
DETERMINE WHERE THE GREATER SEVERE THREAT DEVELOPS DURING THE
AFTERNOON. MODEST SOUTHWESTERLY FLOW ALOFT WILL DRIVE THE
DEVELOPMENT OF THE LEE TROUGH THAT WILL ADVECT UPPER 50S TO LOW 60S
F DEWPOINTS INTO THE HIGH PLAINS. A SUBTLE SHORTWAVE TROUGH DEPICTED
IN MOST GUIDANCE WILL INITIATE CONVECTION WITHIN THE HIGHER TERRAIN
OF EASTERN MONTANA/WYOMING AND THE BLACK HILLS. INITIAL SUPERCELLS
WILL BE CAPABLE OF LARGE TO VERY LARGE HAIL AND SEVERE WINDS.
ADDITIONAL CONVECTION IS ALSO POSSIBLE FARTHER SOUTHEAST ALONG THE
OUTFLOW BOUNDARY WHERE A WEAK SURFACE LOW MAY ENHANCE LOW-LEVEL LIFT
OF A WEAKLY CAPPED AIRMASS. A SIMILAR THREAT FOR LARGE/VERY LARGE
HAIL AND SEVERE WINDS WOULD ACCOMPANY THIS ACTIVITY. SHOULD THE
ACTIVITY FARTHER EAST REMAIN DISCRETE INTO EARLY EVENING, A
MARGINALLY GREATER TORNADO RISK WOULD EXIST. BETWEEN THESE TWO ZONES
OF CONVECTION, UPSCALE GROWTH WILL ALLOW ONE OR MORE MCS TO DEVELOP
AND TRACK ALONG THE BOUNDARY. THE LEAD MCS WOULD HAVE GREATER
POTENTIAL FOR SEVERE WINDS (SOME 75+ MPH). THE LOW-LEVEL JET
RESPONSE DURING THE EVENING WILL NOT BE OVERLY STRONG, BUT IT SHOULD
BE ENOUGH TO HELP CONVECTION TO CONTINUE INTO PARTS OF IOWA LATER IN
THE EVENING.
..NORTHERN ILLINOIS INTO NORTHWEST OHIO
WITH AN MCV AND RELATED CONVECTION LIKELY MOVING THROUGH THE GREAT
LAKES REGION TO THE NORTH, AN OUTFLOW/THETA-E BOUNDARY WILL SETTLE
SOMEWHERE WITHIN THESE AREAS. MODEL GUIDANCE SUGGESTS THAT HEATING
ALONG THIS BOUNDARY WILL PROMOTE SCATTERED STORM DEVELOPMENT. MODEST
ENHANCEMENT TO DEEP-LAYER SHEAR DUE TO THE MCV MAY ALLOW FOR MODEST
ORGANIZATION OF A CLUSTER/LINEAR SEGMENT THAT TRAVELS EAST ALONG THE
BOUNDARY. WIND PROBABILITIES HAVE BEEN INCREASED TO ACCOUNT FOR THIS
POTENTIAL.
..MID-ATLANTIC
MODEL SPREAD STILL EXISTS AS TO WHERE THE GREATEST STORM COVERAGE
WILL EXIST DURING THE AFTERNOON. TEMPERATURES NEARING 100 F AND 60S
F DEWPOINTS WILL SUPPORT STRONG DESTABILIZATION ACROSS THE REGION.
THE DEGREE OF TEMPERATURE-DEWPOINT SPREADS WILL PROMOTE EFFICIENT
DOWNDRAFT PRODUCTION. EFFECTIVE SHEAR WILL BE GREATEST IN THE
NORTHERN MID-ATLANTIC WHERE AROUND 30 KT OF FLOW AT 500 MB WILL
EXIST. THIS SHOULD PROMOTE CLUSTERS/LINEAR SEGMENTS CAPABLE OF WIND
DAMAGE. TOWARDS THE BLUE RIDGE, STORM COVERAGE IS MUCH LESS CERTAIN
GIVEN THE VERY WEAK FORCING. DAMAGING DOWNBURSTS ARE STILL POSSIBLE
WITH STORMS THAT CAN DEVELOP. MODEL TRENDS WILL CONTINUE TO BE
MONITORED FOR ANY INCREASE IN EXPECTED STORM COVERAGE.
..TENNESSEE VALLEY INTO OHIO VALLEY
STRONG HEATING OF A MID/UPPER 60S F DEWPOINT AIRMASS WILL PROMOTE
4000+ J/KG MLCAPE BY THE AFTERNOON. WEAK SHEAR WILL LIMIT STORM
ORGANIZATION, BUT SUBTLE SHORTWAVE TROUGHS MOVING AROUND THE UPPER
ANTICYCLONE COULD ALLOW FOR LOCALLY GREATER STORM
COVERAGE/CLUSTERING. DAMAGING DOWNBURST WINDS ARE THE EXPECTED
HAZARD.
..NORTHERN PLAINS INTO UPPER MIDWEST
FORECAST UNCERTAINTY REMAINS MEDIUM TO HIGH IN TERMS OF HOW MUCH
DESTABILIZATION WILL OCCUR WITHIN THESE AREAS. GUIDANCE GENERALLY
SUGGESTS CONVECTION/CLOUD COVER WILL EXIST DURING THE MORNING AND
POTENTIALLY PARTS OF THE AFTERNOON. A BROAD MARGINAL REMAINS IN
PLACE FOR DAMAGING WINDS AND ISOLATED LARGE HAIL POTENTIAL SHOULD
ENOUGH DESTABILIZATION OCCUR.
..WENDT.. 07/02/2026
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