375  
FXUS63 KOAX 042333  
AFDOAX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE  
633 PM CDT TUE AUG 4 2026  
   
KEY MESSAGES
 
 
- RAIN CHANCES SHIFT TO SOUTHEAST NEBRASKA AND SOUTHWEST IOWA  
TUESDAY EVENING INTO WEDNESDAY (60-90% CHANCE).  
 
- MILDER TEMPERATURES THROUGH THURSDAY, WARMING BACK UP GOING  
INTO THE WEEKEND. DRY, SEASONABLY WARM WEATHER EXPECTED OVER  
THE WEEKEND.  
 
- WILDFIRE SMOKE CONTINUES TO DRIFT IN FROM THE NORTH. A SMALL  
AMOUNT MAY BE FOUND AT THE SURFACE. MOST WILL BE ELEVATED AND  
MAY PRODUCE SOME HAZY SKIES.  
 

 
   
DISCUSSION
 
 
ISSUED AT 200 PM CDT TUE AUG 4 2026  
 
SURFACE ANALYSIS SHOWS THE COOLER CANADIAN AIR HAS PUSHED  
THROUGH ALL BUT THE LAST SOUTHEASTERN COUNTIES OF THE CWA.  
BEHIND THE FRONT, TEMPS ARE MOSTLY IN THE 60S AND 70S WITH BRISK  
NORTHERLY WINDS. AHEAD OF IT, FALLS CITY, NEBRASKA CITY, AND  
SOUTHWEST IOWA HAVE MANAGED 80 BEFORE THE COOLER AIR HAS ARRIVED.  
KOAX HAS BEEN INTERPRETING RETURNS FROM RAIN SINCE BEFORE  
SUNRISE. RADAR ESTIMATES SUGGEST SOME LOCATIONS BETWEEN NORFOLK  
AND SIOUX CITY (INCLUDING WAYNE) HAVE RECEIVED 1.5". GROUND  
TRUTH SHOWS GAUGES MOSTLY REPORTING CLOSER TO HALF OF THAT.  
 
THESE SHOWERS AND ASSOCIATED LIGHTNING/THUNDER ARE SLOWLY  
SLIDING EAST/SOUTHEAST AND ARE EXPECTED TO DISSIPATE AND PUSH  
OUT OF THE SOUTHEASTERN CORNER CWA BY ABOUT 7PM TONIGHT AS THE  
SHORTWAVE RESPONSIBLE FOR THEIR FORCING CONTINUES EAST.  
 
THE DRY SPELL WON'T LAST LONG AS ANOTHER VORT MAX - CURRENTLY  
OVER THE HIGH COUNTRY OF COLORADO - PUSHES THROUGH OVERNIGHT.  
THAT COMBINED WITH THE EXTRA LIFT PROVIDED BY THE SUMMER  
NOCTURNAL JET, AND LIKELY POPS (80-90%) ARE EXPECTED IN THE  
AREAS WITHIN 50 MILES OF I-80. WITH PWAT VALUES NEAR THE 90TH  
PERCENTILE FOR AUGUST, SOME LOCALIZED HEAVY RAIN IS POSSIBLE IN  
THE URBAN AREAS OF OMAHA AND LINCOLN. CAM QPF SUGGESTS RAINFALL  
OF 3.5" IS POSSIBLE AT OMAHA, WHICH WOULD OVERWHELM THE CITY'S  
DRAINAGE SYSTEM. CONSIDERED A FLOOD WATCH, BUT WILL HOLD OFF FOR  
NOW DUE TO LOW CONFIDENCE AS TO WHERE THE QPF BULLSEYE IS MOST  
LIKELY TO SET UP, BUT WESTERN IOWA/OMAHA METRO HAS BEST ODDS.  
 
THE SPC ADDED AN AREA OF "MARGINAL THREAT" FOR SEVERE WEATHER  
THIS EVENING. MOST OF THE LIFT IS DISPLACED NORTH OF THE FRONT,  
BUT JUST AHEAD OF IT, THERE IS 1500 J/KG OF CAPE AND 40-50 KNOTS  
OF BULK SHEAR. SHOULD A STORM TAP INTO THAT INSTABILITY, IT  
COULD PRODUCE SOME BORDERLINE SEVERE WEATHER.  
 
OVERNIGHT'S INSTABILITY WILL BE ELEVATED... LEAVING LOTS OF  
THUNDER AND LIGHTNING, BUT LITTLE SEVERE THREAT.  
   
WEDNESDAY
 
 
RAINFALL WILL CONTINUE OVER THE SOUTHERN HALF OF THE AREA  
THROUGH WEDNESDAY'S FIRST HALF BEFORE CONTINUING SOUTHEAST.  
 
SKIES WILL BE CLEARING FROM NORTH TO SOUTH, BUT THEY'LL REMAIN  
MARRED BY THE WILDFIRE SMOKE DRIFTING IN FROM CANADA. EXPECT A  
20-30% REDUCTION IN SUNLIGHT. THERE MAY BE SOME SMOKE FOUND AT  
THE SURFACE, TOO, BUT MODELS SEEM TO BE OVERDOING IT SO FAR  
BASED ON OBSERVATIONS FROM UP NORTH AND I HAVE OPTED NOT TO  
INCLUDE IT IN THE FORECAST FOR NOW.  
 
TEMPERATURES WILL BE COOLER FOR WEDNESDAY BEHIND THE FRONT WITH  
HIGHS RELEGATED MOSTLY TO THE 70S AS HIGH PRESSURE WORKS IN FROM  
THE NORTH.  
   
THURSDAY AND BEYOND
 
 
SOUTHERLY RETURN FLOW DEVELOPS AS THE SFC HIGH SLIDES EAST.  
THOSE WINDS HELP PUSH TEMPS PAST THE 80F MARK. MORE SHOWERS AND  
STORMS ARE POSSIBLE LATE ON THURSDAY NIGHT AS ANOTHER SHORTWAVE  
SWEEPS THROUGH KANSAS.  
 
TEMPS WILL CONTINUE TO WARM INTO THE WEEKEND, BUT AS THE H5  
PATTERN BECOMES QUASI-ZONAL, TEMPS SHOULD MODERATE TO NEAR  
SEASONAL AVERAGES OR A FEW DEGREES WARMER INTO THE LOWER 90S.  
 

 
   
AVIATION /00Z TAFS THROUGH 00Z THURSDAY/
 
 
ISSUED AT 633 PM CDT TUE AUG 4 2026  
 
KOMA/KLNK:  
MORE STORMS EXPECTED TO DEVELOP STARTING AROUND 01Z LIKELY  
INITIALLY NORTH OF KOMA. BY AROUND 05Z STORMS SHOULD SPREAD  
SOUTH INTO KOMA AND KLNK BRINGING CIGS BACK DOWN TO 700-1000FT  
AND REDUCING VIS TO 3SM, LESS AT TIMES UNDER HEAVIER RAIN. MOST  
CONFIDENT IN A PERIOD OF STORMS FROM 05-08Z, WITH STORMS  
BECOMING MORE SCATTERED WITH LESS CHANCE OF LIGHTNING AFTER 08Z.  
CIGS WILL REMAIN MOST LIKELY IFR THROUGH THE PERIOD OF HEAVIER  
RAIN THROUGH AROUND 15Z WITH CIGS IMPROVING THROUGH THE REST OF  
THE MORNING INTO THE AFTERNOON. WINDS WILL BE OUT OF THE NORTH  
OVERNIGHT SHIFTING EAST-NORTHEASTERLY STARTING AROUND 15Z.  
 
KOFK:  
KOFK WILL STAY TO THE NORTH OF SHOWERS AND STORMS, REMAINING VFR  
THROUGH THE TAF PERIOD. WINDS OUT OF THE NORTH OVERNIGHT WILL BE  
SHIFTING TO EAST-NORTHEASTERLY BY AROUND 14Z.  
 

 
   
OAX WATCHES/WARNINGS/ADVISORIES
 
 
NE...NONE.  
IA...NONE.  
 

 
 

 
 
DISCUSSION...NICOLAISEN  
AVIATION...MCCOY  
 
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