538  
FXUS64 KOUN 210750  
AFDOUN  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE NORMAN OK  
250 AM CDT SUN JUN 21 2026  
   
..NEW NEAR TERM, SHORT TERM, LONG TERM  
 
   
KEY MESSAGES  
 
UPDATED AT 240 AM CDT SUN JUN 21 2026  
 
- HOT AND HUMID CONDITIONS ARE EXPECTED THIS AFTERNOON WITH TRIPLE  
DIGIT HEAT INDICES.  
 
- AN UNSETTLED PATTERN WITH MULTIPLE ROUNDS OF RAIN/STORMS ARE  
EXPECTED OVER THE NEXT SEVERAL DAYS; SEVERE STORMS AND HEAVY  
RAINFALL ARE POSSIBLE ON TONIGHT AND MONDAY NIGHTS.  
 
- BELOW NORMAL TEMPERATURES ARE FORECAST THIS UPCOMING WORK WEEK.  
 
 
   
NEAR TERM  
 
(THROUGH SUNDAY)  
ISSUED AT 240 AM CDT SUN JUN 21 2026  
 
A MESOSCALE CONVECTIVE COMPLEX (MCS) CONTINUES TO MOVE EASTWARD  
ACROSS KANSAS EARLY THIS MORNING. THE SOUTHERN EDGE OF THIS  
COMPLEX AND ITS ASSOCIATED OUTFLOW BOUNDARY WILL RESULT IN A  
CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS FAR NORTH CENTRAL  
OKLAHOMA.  
 
HOTTER WEATHER IS EXPECTED THIS AFTERNOON AS THE LOW-LEVEL  
THERMAL RIDGE EXPANDS EASTWARD AND STRENGTHENS AHEAD OF AN  
APPROACHING COLD FRONT. HIGH TEMPERATURES ARE FORECAST TO RANGE  
FROM THE LOW 90S (SOUTHEAST) TO LOW 100S DEG F (WEST) WITH TRIPLE  
DIGIT HEAT INDICES.  
 
BY THIS AFTERNOON, THE COLD FRONT IS FORECAST TO ADVANCE INTO  
NORTHERN OKLAHOMA. THE AIR MASS AHEAD OF THE COLD FRONT IS  
FORECAST TO BECOME HIGHLY UNSTABLE (~3000 TO 4000 J/KG OF MLCAPE)  
WITH MODEST VERTICAL WIND SHEAR (~30 TO 35 KNOTS OF EFFECTIVE  
BULK SHEAR), WHICH IS AN ENVIRONMENT SUFFICIENT FOR STRONG TO  
SEVERE THUNDERSTORMS. LOW-COVERGENCE ALONG THE COLD FRONT WILL  
LIKELY BE SUFFICIENT FOR CONVECTION INITIATION BY LATE AFTERNOON  
INTO THE EARLY EVENING.  
 
INITIAL THUNDERSTORMS WILL LIKELY BE DISCRETE WITH SUPERCELL  
CHARACTERISTICS THAT WILL HAVE A THREAT FOR LARGE HAIL (AT LEAST  
UP TO GOLF BALLS), DAMAGING WIND GUSTS (UP TO 70 MPH), AND A VERY  
LOW TORNADO RISK. WITH TIME, UPSCALE GROWTH/CONSOLIDATION INTO  
CLUSTERS OF THUNDERSTORMS IS EXPECTED. HEAVY RAINFALL/FLOODING MAY  
BECOME AN INCREASING HAZARD OVERNIGHT AS A STRENGTHENING LOW-  
LEVEL JET WILL FAVOR CONTINUED REDEVELOPMENT OF ELEVATED, TRAINING  
THUNDERSTORMS.  
 
MAHALE  
 
 
   
SHORT TERM  
 
(SUNDAY NIGHT THROUGH TUESDAY NIGHT)  
ISSUED AT 240 AM CDT SUN JUN 21 2026  
 
MONDAY'S WEATHER WILL BE HIGHLY DEPENDENT ON HOW FAR SOUTH THE  
EFFECTIVE, CONVECTIVELY-REINFORCED COLD FRONT ADVANCES SUNDAY  
NIGHT INTO MONDAY MORNING. CURRENTLY, IT APPEARS THE FRONT WILL BE  
SOMEWHERE BETWEEN I-40 AND THE RED RIVER--BUT FORECAST  
UNCERTAINTY IS RELATIVELY HIGH AS IT WILL DEPEND ON HOW  
WIDESPREAD THUNDERSTORM COVERAGE IS TONIGHT.  
 
THERE WILL BE A NORTH TO SOUTH TEMPERATURE GRADIENT WITH MUCH  
COOLER WEATHER NORTH OF THE FRONT MONDAY AFTERNOON WITH HIGHS IN  
THE LOW TO MID 80S DEG F. SOUTH OF THE FRONT, TEMPERATURES WILL  
RISE BACK INTO THE 90S DEG F.  
 
SHOWERS AND THUNDERSTORMS WILL LIKELY DEVELOP IN CLOSE PROXIMITY  
TO THE FRONT/REMNANT BOUNDARY DURING THE DAY MONDAY. INCREASING  
ASCENT FROM AN APPROACHING WAVE AND A STRENGTHENING LOW-LEVEL JET  
MONDAY NIGHT WILL LIKELY FURTHER INCREASE SHOWER/THUNDERSTORM  
COVERAGE NEAR AND EVEN NORTH OF THE FRONT. STRONG TO SEVERE  
THUNDERSTORMS ARE POSSIBLE ALONG WITH A THREAT FOR HEAVY  
RAINFALL/FLOODING.  
 
ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS IS POSSIBLE LATE  
TUESDAY INTO TUESDAY NIGHT AS ANOTHER SHORTWAVE TROUGH EMBEDDED IN  
THE NORTHWEST FLOW APPROACHES THE SOUTHERN PLAINS. THERE WILL BE  
A RISK OF STRONG TO SEVERE THUNDERSTORMS, ESPECIALLY ACROSS  
NORTHWEST OKLAHOMA, AND A THREAT FOR HEAVY RAINFALL/FLOODING.  
 
MAHALE  
 
 
   
LONG TERM  
 
(WEDNESDAY THROUGH SATURDAY)  
ISSUED AT 240 AM CDT SUN JUN 21 2026  
 
NORTHWEST TO WEST-NORTHWEST FLOW WILL CONTINUE TO PERSIST ACROSS  
THE SOUTHERN PLAINS THROUGH AT LEAST FRIDAY WITH A MID-LEVEL RIDGE  
REMAINING QUASI-STATIONARY ACROSS THE SOUTHWEST U.S INTO NORTHERN  
MEXICO.  
 
WITH NORTHWEST FLOW ALOFT, AN ACTIVE WEATHER PATTERN WILL  
CONTINUE AS EMBEDDED SHORTWAVES WITHIN THE FLOW MOVE ACROSS THE  
PLAINS. AS THESE WAVES PASS BY, THERE WILL BE ONGOING CHANCES FOR  
SHOWERS AND THUNDERSTORMS AS MCSS AND/OR EFFECTIVE COLD FRONTS  
ADVANCE SOUTHWARD. THE HIGHEST CHANCE FOR SHOWERS AND  
THUNDERSTORMS WILL GENERALLY BE IN THE OVERNIGHT/EARLY MORNING  
HOURS. WITH RESPECT TO LOCATION, THE HIGHEST CHANCES WILL BE  
ACROSS NORTHERN OKLAHOMA WITH DECREASING CHANCES WITH SOUTHWARD  
EXTENT. THESE COMPLEXES OF THUNDERSTORMS AND THEIR EFFECTIVE,  
CONVECTIVELY-REINFORCED COLD FRONTS SHOULD RESULT IN SEASONABLE TO  
SLIGHTLY BELOW NORMAL TEMPERATURES.  
 
BY THE LATE INTO THE UPCOMING WEEKEND INTO NEXT WEEK,  
DETERMINISTIC AND ENSEMBLE DATA INDICATE A MID-LEVEL RIDGE MAY  
STRENGTHEN TO OUR EAST. THIS WOULD RESULT IN HOTTER AND DRIER  
WEATHER ACROSS THE SOUTHERN PLAINS.  
 
MAHALE  
 
 
   
AVIATION  
 
(06Z TAFS)  
ISSUED AT 1032 PM CDT SAT JUN 20 2026  
 
A THUNDERSTORM COMPLEX COMING DOWN THE CENTRAL HIGH PLAINS COULD  
IMPACT 3 OF OUR TERMINALS IN NORTHERN OKLAHOMA THROUGH 12Z. AS A  
RESULT TERMINALS KWWR, KPNC, AND KSWO COULD BRIEFLY REDUCE DOWN TO  
AN IFR CATEGORY WITH A LOWERED CEILING AND REDUCED VISIBILITY IN  
RAIN ALTHOUGH THE LATTER TWO COULD STAY IN AN IFR CATEGORY DUE TO  
STRATUS UP TO 15Z. ANOTHER STORM SYSTEM ALONG A COLD FRONT PASSAGE  
WILL INCREASE AFTER 19Z ACROSS NORTHERN OKLAHOMA REACHING THE  
I-40 CORRIDOR BY 01Z AS 30% PROBABILITIES ARE IN PLACE AT  
TERMINALS KCSM AND THE OKLAHOMA CITY METRO (KOKC & KOUN).  
 
SURFACE WINDS CURRENTLY OUT OF THE SOUTHEAST BUT EXPECTED TO VEER  
MORE SOUTHERLY BY 12Z AT 15 KTS GUSTING TO 20 KTS. BY 16Z SOUTH-  
SOUTHWEST WINDS INCREASING 15-20 KTS WILL GUSTING UP TO 30 KTS AS  
WE START MIXING HIGHER INTO A LOW-LEVEL JET. AT CURRENT TIME THE  
LOW-LEVEL JET IS STRENGTHENING OUT OF THE SOUTH INCREASING TO 35  
KTS FLOW WHICH COULD PRODUCE LOW-LEVEL WIND SHEAR ACROSS OUR  
TERMINALS. A COLD FRONT WILL START PUSHING INTO NORTHERN OKLAHOMA  
BETWEEN 00-03Z SHIFTING SURFACE WINDS OUT OF THE NORTHEAST BEHIND  
IT.  
 
 
   
PRELIMINARY POINT TEMPS/POPS  
 
OKLAHOMA CITY OK 95 72 86 68 / 0 60 40 90  
HOBART OK 97 72 90 68 / 0 40 40 70  
WICHITA FALLS TX 95 75 94 72 / 0 30 30 50  
GAGE OK 102 66 84 64 / 10 40 50 60  
PONCA CITY OK 95 67 80 65 / 30 60 20 70  
DURANT OK 92 78 92 76 / 0 40 50 50  
 
 
   
OUN WATCHES/WARNINGS/ADVISORIES  
 
OK...HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 8 PM CDT THIS EVENING  
FOR OKZ005>008-011>013-015>027-033>039-044-045.  
 
TX...HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 8 PM CDT THIS EVENING  
FOR TXZ083>090.  
 
 
 
 
 
NEAR TERM...10  
SHORT TERM...10  
LONG TERM....10  
AVIATION...68  
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