474  
ACUS01 KWNS 150056  
SWODY1  
SPC AC 150054  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0754 PM CDT TUE APR 14 2026  
 
VALID 150100Z - 151200Z  
 
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROS PORTIONS  
OF THE GREAT LAKES REGION...  
   
..SUMMARY  
 
SEVERE THUNDERSTORMS ARE EXPECTED THROUGH TONIGHT FROM THE SOUTHERN  
PLAINS INTO THE MIDWEST. LARGE HAIL, SEVERAL TORNADOES (SOME  
STRONG), AND SWATHS OF SEVERE/DAMAGING GUSTS ARE ALL LIKELY,  
PARTICULARLY FROM EASTERN IOWA INTO THE SOUTHERN GREAT LAKES.  
   
..SYNOPSIS  
 
SCATTERED DISCRETE/SEMI-DISCRETE SUPERCELLS ARE ONGOING ACROSS  
EASTERN IOWA, FAR NORTHERN ILLINOIS, AND SOUTHERN WISCONSIN ALONG A  
DIFFUSE WARM FRONTAL ZONE STRETCHING EASTWARD FROM WEAK SURFACE LOW  
ANALYZED OVER EASTERN NE/WESTERN IA. THE PRIMARY SEVERE RISK THROUGH  
THE OVERNIGHT HOURS WILL BE ASSOCIATED WITH THIS ACTIVITY AS IT  
SPREADS SOUTHEAST THROUGH EARLY MORNING. FURTHER SOUTH ACROSS THE  
CENTRAL/SOUTHERN PLAINS, POORLY ORGANIZED CONVECTION CASTS  
UNCERTAINTY IN THE NOCTURNAL SEVERE THREAT; HOWEVER, A FAVORABLE  
ENVIRONMENT WILL REMAIN IN PLACE THROUGH WEDNESDAY MORNING AND COULD  
SUPPORT SEVERE CONVECTION.  
   
..MIDWEST/GREAT LAKES  
 
01 UTC REGIONAL RADAR MOSAICS SHOW SEMI-DISCRETE SUPERCELLS ONGOING  
ACROSS FAR EASTERN IA, NORTHERN IL, AND SOUTHERN WI WITH THE EARLY  
STAGES OF UPSCALE GROWTH EVIDENT AS STORMS INTERACTIONS INCREASE.  
THIS TREND WILL CONTINUE THROUGH THE OVERNIGHT HOURS AS THIS  
ACTIVITY PROPAGATES EAST/SOUTHEAST INTO LOWER MI AND NORTHERN IN.  
THE RECENT 00Z DVN RAOB SAMPLED A CONVECTIVE ENVIRONMENT HIGHLY  
FAVORABLE FOR ORGANIZED CONVECTION, WHICH WILL MAINTAIN THE  
POTENTIAL FOR SIGNIFICANT HAIL AND TORNADOES IN THE NEAR TERM (MOST  
LIKELY THROUGH 03 UTC) BEFORE A FULL TRANSITION TO A LINEAR MODE  
TAKES PLACE. ONCE THIS TRANSITION OCCURS, SEVERE WINDS (INCLUDING  
THE POTENTIAL FOR SIGNIFICANT GUSTS IN EXCESS OF 75 MPH) AND  
EMBEDDED CIRCULATIONS APPEAR PROBABLE FOR AREAS DOWNSTREAM.  
   
..SOUTHERN IOWA INTO KANSAS  
 
THUNDERSTORM DEVELOPMENT ALONG A SOUTHWARD SAGGING COLD FRONT IS  
ANTICIPATED IN THE COMING HOURS ACROSS NORTHEAST KS INTO SOUTHERN  
IA. REGIONAL SOUNDINGS SAMPLED ADEQUATE BUOYANCY AND STRONG  
DEEP-LAYER WIND SHEAR (AROUND 50 KNOTS) THAT WILL LIKELY SUPPORT  
ORGANIZED CONVECTION ALONG THE FRONT FOR A FEW HOURS. STORM MOTIONS  
ALONG THE BOUNDARY MAY FOSTER CLUSTERING/UPSCALE GROWTH, BUT A  
SEVERE WIND, HAIL, AND PERHAPS TORNADO THREAT IS EXPECTED TO  
MATERIALIZE THROUGH THE NIGHT.  
   
..OKLAHOMA INTO TEXAS  
 
CONVECTIVE EVOLUTION THUS FAR ACROSS WESTERN OK INTO NORTHWEST TX  
HAS BEEN RELATIVELY LACKLUSTER GIVEN THE OTHERWISE BUOYANT AND  
STRONGLY SHEARED ENVIRONMENT SAMPLED BY THE 00Z OUN SOUNDING. THIS  
IS LIKELY DUE TO EXPANSIVE CONVECTIVE OUTFLOWS RESULTING IN  
UNDERCUTTING AND CLUSTERED STORM MODES AS WELL AS THE PRESENCE OF A  
SUBSIDENCE INVERSION (ALSO NOTED IN THE 00Z SOUNDING). IT REMAINS  
UNCLEAR WHETHER OR NOT THIS ACTIVITY WILL BE ABLE TO RE-INTENSIFY  
THROUGH THE LATE EVENING HOURS GIVEN. HOWEVER, STRENGTHENING FLOW  
FIELDS THROUGH 06 UTC MAY SUPPORT SOME DEGREE OF IMPROVED  
ORGANIZATION AND A MORE ROBUST SEVERE THREAT. THIS POTENTIAL IS  
HINTED BY RECENT HRRR SOLUTIONS, BUT OVERALL CONFIDENCE IS LIMITED.  
BASED ON THESE TRENDS, OPTED TO REMOVE THE 30% HAIL/WIND  
PROBABILITIES GIVEN LOW CONFIDENCE IN SEVERE COVERAGE. FURTHER SOUTH  
INTO WESTERN TX, ATTEMPTS AT SUSTAINED CONVECTION HAVE BEEN NOTED  
OVER THE PAST HOUR ALONG THE DRYLINE, BUT DOWNSTREAM INHIBITION MAY  
LIMIT OVERALL STORM COVERAGE.  
 
..MOORE.. 04/15/2026  
 
 
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