888  
ACUS01 KWNS 151948  
SWODY1  
SPC AC 151946  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0246 PM CDT WED JUL 15 2026  
 
VALID 152000Z - 161200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
THE MID-ATLANTIC...NORTHERN NEW ENGLAND...NORTHERN ROCKIES/HIGH  
PLAINS...PACIFIC NORTHWEST...ARIZONA...AND SOUTH-CENTRAL TEXAS...  
   
..SUMMARY  
 
THERE IS A CONDITIONAL RISK FOR SEVERE THUNDERSTORMS CAPABLE OF  
PRODUCING LARGE HAIL AND DAMAGING WINDS ACROSS PARTS OF THE  
MID-ATLANTIC THIS AFTERNOON AND EVENING. ISOLATED DAMAGING WINDS  
APPEAR POSSIBLE FOR PORTIONS OF NORTHERN NEW ENGLAND, THE NORTHERN  
ROCKIES/HIGH PLAINS, PACIFIC NORTHWEST, AND ARIZONA. A BRIEF TORNADO  
OR TWO MAY ALSO OCCUR ACROSS PARTS OF SOUTH-CENTRAL TEXAS.  
   
..20Z UPDATE  
 
THE PREVIOUS FORECAST REMAINS ON TRACK WITH ONLY MINOR ADJUSTMENTS  
MADE, PREDOMINATELY ACROSS SOUTHERN MONTANA WHERE GUIDANCE HAS  
TRENDED TOWARDS A SLIGHTLY HIGHER COVERAGE OF THUNDERSTORMS WITHIN  
AN ENVIRONMENT FAVORABLE FOR STRONG/SEVERE WINDS. THESE TRENDS ARE  
SUPPORTED BY RECENT MRMS MOSAICS WHICH DEPICT CONVECTION DEVELOPING  
ALONG THE WY/MT BORDER (SEE MCD #1624 FOR ADDITIONAL INFORMATION).  
   
..TEXAS  
 
ALTHOUGH THUNDERSTORM COVERAGE HAS BEEN DECREASING SINCE LATE  
MORNING ACROSS PORTIONS OF CENTRAL/SOUTHERN TX, RECENT VWP  
OBSERVATIONS CONTINUE TO SHOW A STRONGLY SHEARED ENVIRONMENT ACROSS  
THE GREATER SAN ANTONIO AREA WITH 0-1 KM SRH ON THE ORDER OF 100-200  
M2/S2. ADDITIONALLY, CLEARING SKIES AND WARMING TEMPERATURES ARE  
CONTRIBUTING TO DESTABILIZATION ACROSS PARTS OF THE REGION, AND LIFT  
ASSOCIATED WITH A DEPARTING MID-LEVEL WAVE CONTINUES TO INFLUENCE  
THE REGION. CONSEQUENTLY, SOME POTENTIAL REMAINS FOR ORGANIZED  
CONVECTION THROUGH LATE AFTERNOON. DIMINISHING WIND FIELDS THROUGH  
THE EVENING SHOULD GRADUALLY DIMINISH THE SEVERE THREAT TONIGHT.  
 
SEE MCD #1625 AND THE PREVIOUS DISCUSSION BELOW FOR ADDITIONAL  
FORECAST DETAILS.  
 
..MOORE.. 07/15/2026  
   
PREV DISCUSSION  
/ISSUED 1131 AM CDT WED JUL 15 2026/  
   
..NORTHERN MID-ATLANTIC INTO THE NORTHEAST  
 
RECENT SURFACE ANALYSIS PLACES A COLD FRONT FROM NORTHERN ME  
SOUTHWESTWARD INTO NORTHERN NY BEFORE ARCING WESTWARD ACROSS  
SOUTHEASTERN ONTARIO AND WEST-NORTHWESTWARD ACROSS NORTHERN MI AND  
FAR NORTHERN WI INTO CENTRAL MN. EASTERN PORTION OF THIS FRONT IS  
EXPECTED TO PUSH SOUTHEASTWARD THROUGH THE NORTHEAST TODAY, MOVING  
AHEAD OF A LOW-AMPLITUDE AND PROGRESSIVE SHORTWAVE TROUGH CURRENTLY  
MOVING THROUGH EASTERN ONTARIO INTO FAR SOUTHERN QUEBEC. LARGE-SCALE  
ASCENT ASSOCIATED WITH THIS WAVE WILL SPREAD ACROSS THE REGION, BUT  
WARM TEMPERATURES ALOFT WILL LIKELY LIMIT THUNDERSTORM COVERAGE  
ACROSS MUCH OF THE REGION. A BAND OF LOW-TOPPED SHOWERS AND  
ISOLATED/BRIEF THUNDERSTORMS MAY DEVELOP DURING THE AFTERNOON  
ACROSS NORTHERN NEW ENGLAND, WHERE FORCING FOR ASCENT WILL BE THE  
STRONGEST. OVERALL BUOYANCY WILL BE MODEST, BUT STEEPENING LOW-LEVEL  
LAPSE RATES, A UNIDIRECTIONAL/WESTERLY WIND PROFILE WITH HEIGHT  
THROUGH MID LEVELS, AND 30-40 KT OF FLOW AROUND 1-2 KM AGL WILL  
SUPPORT THE POTENTIAL FOR LOCALLY DAMAGING WIND GUSTS.  
 
FARTHER SOUTH IN THE NORTHERN MID-ATLANTIC, WARM AND MOIST  
CONDITIONS WILL PERSIST SOUTH OF THE FRONT. HOWEVER, WARM MID-LEVEL  
TEMPERATURES MAY PREVENT THE AIRMASS FROM FULLY DESTABILIZING, WITH  
LINGERING CONVECTIVE INHIBITION LIKELY. GIVEN THIS INHIBITION AND  
DISPLACEMENT FARTHER SOUTH OF THE STRONGER FORCING FOR ASCENT,  
ROBUST CONVECTIVE DEVELOPMENT REMAINS HIGHLY UNCERTAIN.  
ADDITIONALLY, RESIDUAL SMOKE COULD ALSO LIMIT HEATING, KEEPING  
CONVECTIVE INHIBITION IN PLACE. THAT BEING SAID, STRONG DEEP-LAYER  
WESTERLY FLOW AND STEEP MID-LEVEL LAPSE RATES WOULD SUPPORT STRONG  
OUTFLOW AND PERHAPS EVEN ISOLATED HAIL WITH ANY STORMS THAT CAN  
DEVELOP AND MATURE.  
   
..NORTHERN WYOMING INTO SOUTHERN MONTANA  
 
RECENT SATELLITE IMAGERY SHOWS A WEAK VORTICITY MAXIMUM OVER EASTERN  
ID. THIS VORTICITY MAX IS FORECAST MOVE NORTHEASTWARD TODAY ACROSS  
THE NORTHERN ROCKIES AND INTO THE ADJACENT NORTHERN HIGH PLAINS.  
DIURNAL HEATING ACROSS THE HIGHER TERRAIN COUPLED WITH  
THE GLANCING INFLUENCE OF THIS SUBTLE DISTURBANCE SHOULD FOSTER THE  
DEVELOPMENT OF SCATTERED AFTERNOON THUNDERSTORMS. WEAK TO MODERATE  
INSTABILITY IS FORECAST, WITH A RELATIVELY DEEP AND WELL-MIXED  
BOUNDARY LAYER ACROSS LOWER ELEVATIONS. SCATTERED THUNDERSTORM  
COVERAGE COULD RESULT IN SOME UPSCALE GROWTH INTO A LOOSELY  
ORGANIZED CLUSTER WITH COLD POOL ORGANIZATION, AND A RISK FOR  
ISOLATED SEVERE WIND GUSTS INTO THE EVENING. HOWEVER, THE OVERALL  
SEVERE THREAT SHOULD BE TEMPERED BY MODEST DEEP-LAYER SHEAR AND  
LIMITED STORM DURATION.  
   
..PACIFIC NORTHWEST  
 
MULTIPLE ROUNDS OF ISOLATED TO SCATTERED THUNDERSTORMS ARE POSSIBLE  
THIS AFTERNOON ALONG AND EAST OF THE CASCADES FROM CENTRAL OR INTO  
SOUTHERN WA. THE FIRST ROUND DURING THE AFTERNOON WILL BE AIDED BY  
OROGRAPHIC INFLUENCES AND A WEAK SHORTWAVE TROUGH PRECEDING A CLOSED  
UPPER LOW OFF THE COAST OF THE PACIFIC NORTHWEST. HIGH CLOUD BASES  
AND A DEEPLY MIXED BOUNDARY LAYER WILL SUPPORT THE POTENTIAL FOR A  
FEW STRONG GUSTS WITH THIS ACTIVITY. ANOTHER ROUND OF STORMS IS  
POSSIBLE LATER THIS EVENING/OVERNIGHT AS ANOTHER WEAK SHORTWAVE  
TROUGH ROUNDS THE UPPER LOW AS THE LOW ITSELF ALSO DRIFTS CLOSER TO  
THE COAST. VERY DRY LOW TO MID-LEVELS WILL PERSIST THROUGHOUT THE  
EVENING/OVERNIGHT, WITH THE POTENTIAL FOR ISOLATED STRONG GUSTS  
REMAINING POSSIBLE.  
   
..SOUTH-CENTRAL TEXAS  
 
WEAK MID-LEVEL LOW OVER SOUTH-CENTRAL TX WILL ONLY DRIFT SLIGHTLY  
WESTWARD TODAY, REMAINING LARGELY IN PLACE WITHIN THE VERY MOIST  
AIRMASS OVER THE REGION. RECENT EWX VAD PROFILES SHOW ABOUT 30 KT OF  
SOUTHERLY FLOW BETWEEN 1-3 KM ALONG THE EASTERN PERIPHERY OF THIS  
LOW. RESULTING HODOGRAPHS SHOW JUST ENOUGH LOW-LEVEL CURVATURE TO  
SUPPORT BRIEF TORNADOES GIVEN THE TROPICAL AIRMASS IN PLACE.  
   
..ARIZONA  
 
WEAK EAST-NORTHEASTERLY MID-LEVEL FLOW IS FORECAST TODAY ACROSS AZ,  
WHICH IS ON THE SOUTHERN PERIPHERY OF UPPER RIDGING EXTENDING ACROSS  
MUCH OF THE CENTRAL CONUS. DAYTIME HEATING OF A SEASONABLY MOIST  
LOW-LEVEL AIRMASS ACROSS SOUTHERN/CENTRAL AZ WILL YIELD MODEST  
INSTABILITY BY MID AFTERNOON. INITIAL DEVELOPMENT IS ANTICIPATED  
OVER THE MOGOLLON RIM AND HIGHER TERRAIN OF SOUTHEAST AZ, BEFORE  
SUBSEQUENTLY SPREADING WESTWARD INTO THE LOWER DESERTS. A DEEPLY  
MIXED BOUNDARY LAYER ACROSS THE LOWER ELEVATIONS COULD SUPPORT  
ISOLATED STRONG TO SEVERE GUSTS.  
 
 
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