960
FXUS63 KOAX 190438
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
1138 PM CDT TUE AUG 18 2026
KEY MESSAGES
- A CLUSTER OF SHOWERS AND STORMS IS EXPECTED (60-80% CHANCE) TO
MOVE ACROSS EASTERN NEBRASKA INTO FAR WESTERN IOWA EARLY
WEDNESDAY MORNING INTO EARLY AFTERNOON. THE STRONGEST STORMS
MAY POSE A LARGE HAIL AND DAMAGING WIND RISK.
- THERE IS A LOW CHANCE (20-40%) OF ADDITIONAL SHOWERS AND
STORMS LATER WEDNESDAY AFTERNOON. THE STRONGEST STORMS MAY
POSE A CONTINUED SEVERE WEATHER RISK.
- A WARMING TREND BEGINS ON THURSDAY WITH TEMPERATURES GRADUALLY
INCREASING INTO THE 80S. PERIODIC RAIN CHANCES (15-30% CHANCE)
REMAIN IN THE FORECAST.
DISCUSSION
ISSUED AT 1137 PM CDT TUE AUG 18 2026
ALL IS QUIET FOR THE MOMENT ACROSS OUR FORECAST AREA. TO OUR SOUTH,
LOW-LEVEL WARM ADVECTION IS SUPPORTING A SEVERE WEATHER AND FLASH
FLOODING THREAT IN THE KANSAS CITY VICINITY. OUR NEXT ROUND OF
STORMS IS JUST BEGINNING TO DEVELOP TO OUR WEST OVER WESTERN
NEBRASKA AND WESTERN SOUTH DAKOTA. THESE SHOWERS AND STORMS ARE A
BIT DISORGANIZED WITH SPORADIC STRONG WINDS AT THIS TIME. THAT WILL
CHANGE AS THIS ACTIVITY GRADUALLY MOVES SOUTHEAST TOWARDS OUR AREA.
AN ENVIRONMENT CHARACTERIZED BY AMPLE SHEAR ABOVE 50 KTS AND MUCAPE
VALUES UP TO 3000 J/KG SHOULD FAVOR A GRADUAL STRENGTHENING AND
ORGANIZATION OF THESE STORMS. FURTHER AIDING THIS WILL BE BROAD
ASCENT AHEAD OF A SHORTWAVE TROUGH OVER THE NORTHERN ROCKIES. WHILE
THERE REMAINS SOME UNCERTAINTY ON THE LEVEL OF MLCIN THAT WILL
DEVELOP OVERNIGHT AHEAD OF THESE STORMS. HIGH-RES MODEL GUIDANCE IS
IN GOOD AGREEMENT THAT A STRONG TO SEVERE THUNDERSTORM COMPLEX WILL
MOVE INTO OUR AREA AROUND AS EARLY AS 4-6 AM CDT EARLY WEDNESDAY
MORNING. THIS COMPLEX IS FORECAST TO MOVE SOUTHEAST THROUGH MUCH OF
EASTERN NEBRASKA AND PERHAPS FA WESTERN IOWA THROUGH THE REMAINDER
OF WEDNESDAY MORNING INTO THE EARLY AFTERNOON. WITH THIS COMPLEX,
LARGE HAIL AND DAMAGING WINDS WILL BE THE MAIN THREAT FROM THE
STRONGEST STORMS. GRADUALLY, THIS COMPLEX WEAKENS AS THE NOCTURNAL
LOW-LEVEL JET SUBSIDES.
LATER WEDNESDAY AFTERNOON, THE FORECAST BECOMES A BIT UNCERTAIN. IT
IS ANTICIPATED THAT MORNING STORMS WILL HELP PUSH A COLD FRONT
THROUGH THE REGION AND END OUR STORM AND SEVERE WEATHER THREAT
EARLY. A COOLER AND MORE STABLE AIRMASS FILTERS IN BEHIND THE FRONT.
THAT SAID, IF THE ATMOSPHERE CAN DESTABILIZE BEHIND MORNING STORMS
AND AHEAD OF THE FRONT, ADDITIONAL SHOWERS AND STORMS MAY DEVELOP.
THESE STORMS WOULD POSE AT LEAST A LOW CHANCE OF SEVERE WEATHER
THROUGH THE REMAINDER OF THE AFTERNOON AND EVENING. BY WEDNESDAY
EVENING, THE FRONT SHOULD CLEAR THE ENTIRE REGION, THUS ENDING STORM
CHANCES.
BY THURSDAY AND BEYOND, A BROAD PATTERN TAKES SHAPE THAT CHANGES
LITTLE THROUGH THE END OF THE FORECAST. THIS PATTERN IS
CHARACTERIZED BY A LARGE RIDGE OVER THE WESTERN CONUS WITH A TROUGH
OVER THE EASTERN CONUS. WE WILL BE SITUATED BETWEEN THESE FEATURES
WITH NORTHWESTERLY UPPER-LEVEL FLOW. TEMPERATURES ARE EXPECTED TO
GRADUALLY WARM THROUGH THE 80S TO END THE WEEK. EXCEPT FOR THURSDAY,
PERIODIC STORM CHANCES REMAIN IN THE FORECAST. BY THIS WEEKEND OUR
NEXT WEATHER SYSTEM IS FORECAST TO APPROACH THE AREA. THIS SYSTEM
WILL MARK THE RETURN OF STORM CHANCES AND PERHAPS SLIGHTLY COOLER
TEMPERATURES. OVERALL, AN EBB AND FLOW OF THIS GENERAL PATTERN OF
SLIGHT WARMING AND PERHAPS DRIER WEATHER TO SLIGHTLY COOLER WEATHER
AND STORM CHANCES SHOULD CHARACTERIZE THE REMAINDER OF THE
FORECAST.
AVIATION /00Z TAFS THROUGH 00Z THURSDAY/
ISSUED AT 606 PM CDT TUE AUG 18 2026
VFR CONDITIONS AND LIGHT WINDS, MAINLY FROM THE NORTHEAST, START
THE PERIOD. SHOWERS AND THUNDERSTORMS ARE ANTICIPATED THIS
EVENING AND EARLY TONIGHT, MAINLY ALONG THE NEBRASKA/KANSAS
BORDER. LOCAL AVIATION IMPACTS ARE NOT EXPECTED WITH THIS. WITH
LIGHT WINDS AND PLENTIFUL MOISTURE, PATCHY FOG IS FORECAST TO
FORM BETWEEN 11-14Z OVER MUCH OF THE AREA. MVFR VISIBILITY
REDUCTIONS WILL BE POSSIBLE WITH ANY FOG THAT DEVELOPS.
ADDITIONAL SHOWERS AND THUNDERSTORMS ARE EXPECTED TO FORM OVER
NORTH-CENTRAL NEBRASKA AFTER 06Z. THIS COMPLEX OF STORMS WILL
SPREAD SOUTHEAST. THE STRONGEST OF THESE THUNDERSTORMS SHOULD
REMAIN WEST OF THE AREA, BUT WEAKER SHOWERS AND THUNDERSTORMS
ARE LIKELY TO IMPACT OFK AND LNK DURING THE MORNING HOURS
(10-16Z). OTHER AREAS MAY SEE IMPACTS, BUT CONFIDENCE IS LOW
DUE TO THE THUNDERSTORM COMPLEX POTENTIALLY LIMITING ADDITIONAL
DEVELOPMENT. THUNDERSTORM CHANCES BEGIN TO DECREASE WEDNESDAY
AFTERNOON AS A COLD FRONT PUSHES SOUTH THROUGH THE AREA.
OAX WATCHES/WARNINGS/ADVISORIES
NE...NONE.
IA...NONE.
DISCUSSION...CHEHAK
AVIATION...CHEHAK
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