261
ACUS01 KWNS 191251
SWODY1
SPC AC 191250
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0750 AM CDT THU JUN 19 2025
VALID 191300Z - 201200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE MID-ATLANTIC...
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHERN PLAINS/UPPER MIDWEST...
..SUMMARY
SEVERE THUNDERSTORMS ARE EXPECTED ACROSS MUCH OF THE MID-ATLANTIC
REGION TODAY, AND TO A LESSER EXTENT INTO THE CAROLINAS AND OVER
PORTIONS OF NEW ENGLAND. SEVERE/DAMAGING WIND GUSTS ARE THE PRIMARY
CONCERN. AN ISOLATED LARGE HAIL THREAT SHOULD ALSO DEVELOP ACROSS
PARTS OF THE NORTHERN PLAINS/UPPER MIDWEST, PRIMARILY DURING THE
EVENING/OVERNIGHT HOURS.
..NEW ENGLAND/MID-ATLANTIC INTO NORTH CAROLINA
AN UPPER TROUGH WILL MOVE EASTWARD TODAY FROM THE GREAT LAKES/OH
VALLEY ACROSS THE MID-ATLANTIC AND NORTHEAST. SEASONABLY STRONG
SOUTHWESTERLY MID-LEVEL FLOW AROUND 40-50 KT WILL ACCOMPANY THIS
UPPER TROUGH PASSAGE, AND AID IN SUFFICIENT DEEP-LAYER SHEAR FOR
ORGANIZED SEVERE THUNDERSTORMS ACROSS THESE REGIONS. RECENT VISIBLE
SATELLITE IMAGERY AND SURFACE OBSERVATIONS SHOW MOSTLY CLEAR SKIES
AND A MOIST LOW-LEVEL AIRMASS ALREADY IN PLACE FROM THE APPALACHIANS
TOWARDS THE MID-ATLANTIC COAST. AMPLE DIURNAL HEATING THROUGH THIS
AFTERNOON SHOULD SUPPORT MODERATE TO LOCALLY STRONG INSTABILITY
ACROSS MUCH OF THE MID-ATLANTIC, WITH SOMEWHAT WEAKER INSTABILITY
WITH NORTHWARD EXTENT INTO INTERIOR NEW ENGLAND.
CURRENT EXPECTATIONS ARE FOR MULTIPLE CELLS/CLUSTERS TO INITIALLY
FORM OVER THE HIGHER TERRAIN OF THE APPALACHIANS/BLUE RIDGE
MOUNTAINS BY EARLY TO MID AFTERNOON, AND SUBSEQUENTLY SPREAD
EAST-NORTHWARD TO THE COAST THROUGH THE AFTERNOON AND EVENING. GIVEN
STEEPENED LOW-LEVEL LAPSE RATES AND ENHANCED LOW/MID-LEVEL FLOW
ASSOCIATED WITH THE UPPER TROUGH, SCATTERED TO POTENTIALLY NUMEROUS
SEVERE/DAMAGING WINDS WILL LIKELY BE THE PRIMARY THREAT WITH THIS
CONVECTION. THE GREATEST CONCENTRATION OF WIND DAMAGE SHOULD BE
FOCUSED ACROSS PARTS OF THE MID-ATLANTIC, WHERE THE ENHANCED RISK
HAS BEEN MAINTAINED WITH ONLY MINOR EXPANSION. OTHERWISE, ISOLATED
HAIL MAY ALSO OCCUR WITH ANY OF THE MORE CELLULAR CONVECTION, EVEN
THOUGH MID-LEVEL LAPSE RATES ARE NOT FORECAST TO BE OVERLY STEEP. A
BRIEF TORNADO OR TWO ALSO APPEARS POSSIBLE, ALTHOUGH LOW-LEVEL WINDS
WILL GENERALLY BE VEERED TO WEST-SOUTHWESTERLY, LIMITING 0-1 KM SRH.
..SOUTHEAST
A BAND OF THUNDERSTORMS IS ONGOING THIS MORNING ACROSS PARTS OF THE
MID-SOUTH/SOUTHEAST. THIS ACTIVITY HAS GENERALLY REMAINED SUB-SEVERE
OVERNIGHT, AND ON THE SOUTHERN PERIPHERY OF AN UPPER TROUGH TO THE
NORTH. WITH STRONG DAYTIME HEATING OF A RATHER MOIST LOW-LEVEL
AIRMASS IN PLACE TO ITS SOUTH AND MODEST DEEP-LAYER SHEAR FOR
UPDRAFT ORGANIZATION, THERE IS SOME OPPORTUNITY FOR THIS CONVECTION
TO EITHER RESTRENGTHEN THROUGH THE AFTERNOON AS IT SPREADS
SOUTHWARD, OR FOR REDEVELOPMENT TO OCCUR ALONG ITS OUTFLOW. HAVE
ADJUSTED THE MARGINAL RISK FOR DAMAGING WINDS BASED ON THE CURRENT
POSITION OF ONGOING THUNDERSTORMS, AND THEIR POTENTIAL TO MOVE
SOUTHWARD ACROSS PARTS OF THE SOUTHEAST/CENTRAL GULF COAST STATES
THIS AFTERNOON/EARLY EVENING BEFORE EVENTUALLY WEAKENING NEAR THE
GULF COAST.
..NORTHERN PLAINS/UPPER MIDWEST
UPPER RIDGING WILL BE MAINTAINED TODAY OVER MUCH OF THE ROCKIES AND
HIGH PLAINS. THIS WILL TEND TO SUPPRESS CONVECTIVE DEVELOPMENT FOR
MUCH OF THE DAY. STILL, A WEAK MID-LEVEL SHORTWAVE TROUGH WILL MOVE
FROM WESTERN CANADA ACROSS THE CANADIAN PRAIRIE PROVINCES TODAY,
EVENTUALLY REACHING PARTS OF THE NORTHERN PLAINS AND UPPER MIDWEST
TONIGHT. THIS FEATURE, ALONG WITH INCREASING LOW-LEVEL WARM/MOIST
ADVECTION ASSOCIATED WITH A STRENGTHENING SOUTHWESTERLY LOW-LEVEL
JET ACROSS THE NORTHERN/CENTRAL PLAINS THIS EVENING, MAY BE
SUFFICIENT TO AID AT LEAST ISOLATED ROBUST THUNDERSTORM DEVELOPMENT
TONIGHT GENERALLY ALONG AND NORTH OF A SURFACE BOUNDARY. STRONG
MUCAPE, STEEP LAPSE RATES ALOFT, AND AMPLE DEEP-LAYER SHEAR WOULD
LIKELY SUPPORT SUPERCELLS WITH ASSOCIATED THREAT FOR LARGE HAIL IN A
FAVORABLE NORTHWESTERLY MID/UPPER-LEVEL FLOW REGIME. THERE IS STILL
SOME UNCERTAINTY WITH THE PLACEMENT AND OVERALL COVERAGE OF THESE
SUPERCELLS TONIGHT, BUT BASED ON LATEST GUIDANCE TRENDS THE SLIGHT
RISK HAS BEEN EXPANDED EASTWARD TO INCLUDE MORE OF CENTRAL/EASTERN
MN AND WESTERN/NORTHERN WI. ISOLATED DAMAGING WINDS MAY ALSO OCCUR
IF AN MCS IS ABLE TO DEVELOP, ALTHOUGH THIS REMAINS HIGHLY
UNCERTAIN.
..CENTRAL PLAINS
MODERATE TO STRONG INSTABILITY IS FORECAST TO DEVELOP THIS AFTERNOON
ACROSS PARTS OF THE CENTRAL PLAINS ALONG/EAST OF SURFACE LEE
TROUGHING. EVEN THOUGH DEEP-LAYER SHEAR AND FORCING ALOFT WILL NOT
BE AS PRONOUNCED AS FARTHER NORTH, THERE APPEARS TO BE SOME CHANCE
FOR HIGH-BASED CONVECTION TO DEVELOP AND POSE AN ISOLATED HAIL/WIND
THREAT.
..GLEASON/KERR.. 06/19/2025
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