016  
ACUS01 KWNS 200102  
SWODY1  
SPC AC 200100  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0800 PM CDT WED AUG 19 2026  
 
VALID 200100Z - 201200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE MID  
MISSISSIPPI AND OHIO VALLEYS AND SOUTHERN ARIZONA...  
   
..SUMMARY  
 
THUNDERSTORMS CAPABLE OF SEVERE WIND GUSTS AND HAIL REMAIN POSSIBLE  
THIS EVENING ACROSS THE MID MISSISSIPPI AND LOWER OHIO VALLEYS AND  
SOUTHERN ARIZONA. MORE ISOLATED STRONG STORMS ARE POSSIBLE THROUGH  
THE EVENING ACROSS PARTS OF THE CENTRAL/SOUTHERN HIGH PLAINS AND  
PARTS OF THE SOUTHEAST.  
 
...MID MS VALLEY TO THE LOWER OH VALLEY.  
EVENING WATER VAPOR IMAGERY SHOWED A BROAD TROUGH AND ENHANCED  
NORTHWESTERLY MID-LEVEL FLOW STRETCHING FROM THE SOUTHERN DAKOTAS  
INTO THE MID MS VALLEY. DOWNSTREAM OF A FLATTENED UPPER RIDGE OVER  
THE SOUTHWEST, THIS TROUGH AND STRONGER FLOW ALOFT SHOULD CONTINUE  
EASTWARD THIS EVENING AIDING IN THUNDERSTORM DEVELOPMENT ACROSS  
PARTS OF THE MID MS AND LOWER OH VALLEYS THIS EVENING.  
 
SEVERAL CLUSTERS OF STORMS ARE ALREADY ONGOING THIS EVENING NEAR A  
DIFFUSE FRONTAL ZONE ACROSS MO AND INTO SOUTHERN IL AND WESTERN KY.  
AS THE UPPER TROUGH APPROACHES, ASCENT FORM A 30+ KT SOUTHWESTERLY  
LOW-LEVEL JET MAY SUPPORT AN INCREASE IN STORM COVERAGE, POSSIBLY  
ALONG THE FLANK OF THE EXIST CLUSTER IN MO AND FARTHER SOUTH ALONG  
THE FRONTAL ZONE LATER THIS EVENING. MODERATE, AND LIKELY SOMEWHAT  
ELEVATED BUOYANCY (2000-3000 J/KG MUCAPE), AND 40-50 KT OF  
DEEP-LAYER SHEAR WILL FAVOR ORGANIZED CLUSTERS OR SUPERCELL  
STRUCTURES. HAIL IS POSSIBLE, ALONG WITH SOME DAMAGING WINDS AND  
PERHAPS A TORNADO, ESPECIALLY IF STORMS CAN DEVELOP INTO A MORE  
COHERENT MCS. THESE STORMS SHOULD SPREAD EASTWARD OVERNIGHT INTO THE  
LOWER OH VALLEY WITH A CONTINUED SEVERE RISK.  
   
..CENTRAL AND SOUTHERN HIGH PLAINS  
 
SCATTERED THUNDERSTORMS, INCLUDING A FEW SUPERCELLS ARE ONGOING  
ACROSS THE CENTRAL AND SOUTHERN HIGH PLAINS WITHIN A BROAD UPSLOPE  
FLOW REGIME. AIDED BY AN UPPER TROUGH WITH MODERATE NORTHWESTERLY  
FLOW ALOFT, ORGANIZED STORMS STRUCTURES CAPABLE OF LARGE HAIL SHOULD  
CONTINUE ALONG THE FOOTHILLS AND ADJACENT HIGH PLAINS THIS EVENING.  
STEEP LAPSE RATES AND LARGE TEMPERATURE-DEW POINT DEPRESSIONS MAY  
ALSO FAVOR A FEW SEVERE GUSTS WITH THE MORE INTENSE CORES/CLUSTERS  
THAT CAN DEVELOP.  
   
..AZ  
 
SCATTERED STORMS ACROSS THE HIGHER TERRAIN OF SOUTHERN AZ SHOULD  
CONTINUE TO MOVE TOWARD THE SOUTHWEST INTO THE LOWER DESERTS THIS  
EVENING. ADEQUATE MONSOON MOISTURE AMID VERY HOT TEMPERATURES (100  
F+) AND STEEP LOW-LEVEL LAPSE RATES WILL SUPPORT STRONG DOWNDRAFTS  
WITH SEVERE GUSTS OF 60-75 MPH POSSIBLE.  
   
..SOUTHEAST  
 
SCATTERED THUNDERSTORMS ARE ONGOING EARLY THIS EVENING FROM MS INTO  
WESTERN/SOUTHERN AL AND ACROSS THE FL PANHANDLE IN ASSOCIATION WITH  
A WEAK MCV. A WARM BOUNDARY LAYER AND SEASONABLY HIGH MOISTURE  
CONTENT SHOULD CONTINUE TO SUPPORT SCATTERED STRONG STORMS THROUGH  
THIS EVENING. PWATS OVER 2 INCHES WILL FAVOR STRONG WATER-LOADED  
DOWNDRAFTS WITH ISOLATED DAMAGING GUSTS POTENTIAL. STORMS SHOULD  
GRADUALLY DIMINISH IN COVERAGE AND INTENSITY TONIGHT AS THE BOUNDARY  
LAYER STABILIZES.  
 
..LYONS.. 08/20/2026  
 
 
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