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FXUS63 KDMX 202348
AFDDMX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
648 PM CDT THU AUG 20 2026
...UPDATED FOR THE 00Z AVIATION DISCUSSION...
KEY MESSAGES
- A FEW ISOLATED STORMS SKIM NORTHERN IOWA OVERNIGHT TONIGHT.
- ADDITIONAL THUNDERSTORMS IN SOUTHWEST IOWA FRIDAY EVENING AND
OVERNIGHT.
- MOSTLY DRY AND SUNNY THROUGH THE WEEKEND!
SHORT TERM /THROUGH FRIDAY NIGHT/
ISSUED AT 222 PM CDT THU AUG 20 2026
HIGH PRESSURE HAS ALLOWED FOR TRANQUIL CONDITIONS ACROSS THE AREA
TODAY WITH A FEW DIURNALLY DRIVEN CLOUDS IN SOUTHERN IOWA.
FARTHER NORTH A SHORTWAVE IS MOVING ACROSS THE UPPER MIDWEST,
RESULTING IN A FEW THUNDERSTORMS ACROSS MINNESOTA. A FEW HIGH
CLOUDS HAVE MOVED ACROSS NORTHERN IOWA ASSOCIATED WITH THIS
WAVE. THE COLD FRONT TRAILS ACROSS SOUTH DAKOTA AND INTO
NEBRASKA THIS AFTERNOON AND WILL MOVE EAST, PUSHING ACROSS IOWA
OVERNIGHT AND ON FRIDAY. BETTER FORCING WILL BE ACROSS MINNESOTA
NEAR THE SURFACE LOW AND SCATTERED THUNDERSTORMS ARE EXPECTED
THERE, EXTENDING ALONG THE FRONT. A FEW OF THESE MAY SKIM
NORTHERN IOWA OVERNIGHT. WHILE AN ISOLATED STRONGER STORM IS
POSSIBLE, THESE WILL LARGELY BE CONFINED NORTH AND WEST OF THE
AREA WHERE FORCING AND INSTABILITY ARE BETTER PHASED.
MUCH OF FRIDAY WILL THEN BE DRY WITH NORTHWEST FLOW HELPING TO
BRING HIGH LEVEL SMOKE FROM FIRES ACROSS THE PACIFIC NORTHWEST.
ANOTHER EMBEDDED WAVE RIDING ALONG THE WESTERN US RIDGE WILL
SLIDE ACROSS NEBRASKA AND SOUTHWEST IOWA FRIDAY EVENING. THIS
WILL BRING ANOTHER CHANCE FOR SCATTERED THUNDERSTORMS. FORCING
IS AGAIN MODEST AND FOCUSED LARGELY WEST OF THE AREA, BUT WITH
1500+ J/KG MLCAPE AND 40 KTS OF SHEAR, A FEW STRONGER TO SEVERE
THUNDERSTORMS ARE POSSIBLE IN THE EVENING.
LONG TERM /SATURDAY THROUGH THURSDAY/
ISSUED AT 222 PM CDT THU AUG 20 2026
ANY LINGERING STORMS IN FAR SOUTHERN IOWA SHOULD CLEAR OUT EARLY
SATURDAY MORNING WITH DRY CONDITIONS THROUGH THE WEEKEND. ANOTHER
EMBEDDED SHORTWAVE WILL MOVE ACROSS IOWA LATE SUNDAY EVENING INTO
MONDAY, SLOWING FROM MODEL SOLUTIONS 24 HOURS AGO. THE UPCOMING
WORK WEEK LOOKS TO REMAIN ACTIVE WITH EMBEDDED SHORTWAVES CONTINUING
TO RIDE ALONG THE WESTERN US RIDGE WITH NORTHWEST FLOW ACROSS IOWA.
A MORE ROBUST SYSTEM LOOKS TO MOVE ACROSS THE AREA ON TUESDAY AND
WILL BE THE NEXT OPPORTUNITY FOR MORE ORGANIZED CONVECTION. AT THIS
TIME RANGE DIFFERENCES REMAIN WITH THE GFS FAVORING A SOUTHERLY
TRACK OVER THE EURO NORTHERLY TRACK.
AVIATION /00Z TAFS THROUGH 00Z SATURDAY/
ISSUED AT 638 PM CDT THU AUG 20 2026
VFR CONDITIONS ONGOING AND LARGELY EXPECTED TO CONTINUE THROUGH
THE TAF PERIOD. CLOUDS AND LOWER CEILINGS ARE EXPECTED TO SKIM
KMCW THIS EVENING AS SHOWERS AND OCCASIONAL STORMS PASS NEARBY.
THESE CEILINGS ARE EXPECTED TO REMAIN VFR AND SHOWERS LARGELY
EXPECTED OUTSIDE OF THE 5 MILE RADIUS AROUND KMCW. THERE IS A
CHANCE FOR A SHOWER/STORM IMPACTING KMCW, BUT CONFIDENCE IS
BELOW 30% NEEDED FOR A PROB 30 GROUP, BUT WILL MONITOR TRENDS
CLOSELY. A FEW OTHER SHOWERS MAY DEVELOP IN PORTIONS OF CENTRAL
IOWA INTO FRIDAY MORNING BUT OVERALL CHANCES ARE BELOW 20% AND
COVERAGE WILL BE ISOLATED AT BEST, SO NO PRECIP MENTIONS
INCLUDED.
DMX WATCHES/WARNINGS/ADVISORIES
NONE.
SHORT TERM...HAGENHOFF
LONG TERM...HAGENHOFF
AVIATION...05
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