387
FXUS63 KDMX 311732
AFDDMX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
1232 PM CDT THU JUL 31 2025
...UPDATED FOR THE 18Z AVIATION DISCUSSION...
KEY MESSAGES
- INCREASING SMOKEY SKIES LATER TODAY AND INTO FRIDAY.
- PLEASANT CONDITIONS THROUGH THE WEEKEND WITH HIGHS IN THE 70S.
DRY UNTIL SUNDAY WHEN SHOWER CHANCES RETURN TO WESTERN IOWA.
UPDATE
ISSUED AT 239 AM CDT THU JUL 31 2025
SHOWERS HAVE DEVELOPED ALONG A WEAK BOUNDARY DRAPED ACROSS NORTHERN
IOWA EARLY THIS MORNING. THESE HAVE REMAINED QUITE LIGHT AND IN
MANY CASES PRECIPITATION IS NOT REACHING THE GROUND. SPRINKLES
ARE EXPECTED TO TAPER OFF THROUGH SUNRISE, SETTING THE STAGE FOR
SEVERAL DRY DAYS UP AHEAD. WITH THIS DRY FORECAST AND AND
TEMPERATURES IN THE 70S, IT SHOULD BE A BEAUTIFUL WEEKEND FOR
THOSE WITH OUTDOOR PLANS. WE DO EXPECT INCREASING SMOKEY SKIES
AS WILDFIRE SMOKE FILTERS IN ACROSS THE AREA. CONCENTRATIONS AT
THE SURFACE LOOK TO REMAIN LOW AT THIS TIME, BUT HAZY SKIES ARE
LIKELY LATER TODAY AND INTO FRIDAY. SHOWERS ARE EXPECTED TO
ARRIVE IN WESTERN IOWA BY SUNDAY WITH A WEAK WAVE INTO THE AREA.
CURRENT PROJECTIONS HAVE WEAK FORCING OR SHEAR, SO ANY SEVERE
RISK IS LOW AT THIS TIME.
DISCUSSION
ISSUED AT 254 PM CDT WED JUL 30 2025
MOST AREAS REMAIN DRY INTO THIS AFTERNOON, WITH THE BULK OF SHOWERS
AND STORMS NOW WELL EAST INTO IL/WI. HOWEVER, A BOUNDARY OVER
NORTHERN IOWA WITH WEAK FORCING OVERHEAD HAS LED TO THE DEVELOPMENT
OF ISOLATED SHOWERS. LOW LEVEL INSTABILITY OVERHEAD ALONG WITH
INCREASED SURFACE VORTICITY RESULTED IN SOME FUNNEL CLOUD REPORTS
OVER NORTHERN IOWA, WHICH PER MODEL GUIDANCE MAY CONTINUE THROUGH
THE REST OF THE AFTERNOON BUT OVERALL SHOULD REMAIN MINIMALLY
IMPACTFUL. IN THE FAR SOUTHEAST PORTION OF THE STATE, THERE ARE SOME
WEAK RETURNS ON RADAR BEHIND THE DEPARTING BOUNDARY INTO IL, WHICH
SHOULD CONTINUE TO MOVE OUT OF THE STATE OVER THE NEXT FEW HOURS AS
WELL. OTHERWISE, TEMPERATURES COMPARED TO THIS TIME YESTERDAY ARE
QUITE LOWER AS COLD AIR ADVECTION TAKES OVER ACROSS THE STATE,
ALLOWING FOR COOLER TEMPERATURES IN THE UPPER 70S FOR HIGHS WITH
SCATTERED CUMULUS ACROSS CENTRAL AND WESTERN IOWA. INTO THIS
EVENING, CAM GUIDANCE CONTINUES TO DEPICT A WEAKENING SHORTWAVE
ENTERING NORTHWESTERN IOWA, WHICH WEAK LIFT OVER THE AREA IS
EXPECTED TO DEVELOP ADDITIONAL ISOLATED TO SCATTERED SHOWERS OVER
WESTERN IOWA AND TRY TO PUSH INTO WEST-CENTRAL IOWA INTO TONIGHT.
GIVEN LOWER INSTABILITY VALUES AROUND 500J/KG AND LIMITED FORCING,
THE OVERALL POTENTIAL FOR STORMS IS LOW BUT CANNOT RULE OUT SOME
OCCASIONAL LIGHTNING THIS EVENING. ADDITIONAL RAINFALL BELOW A HALF
INCH IS EXPECTED, WITH HIGHER AMOUNTS NEAR THE WESTERN BORDER NEAR
AN INCH MAY OCCUR.
INTO THURSDAY, UPPER LEVEL RIDGING ACROSS THE WESTERN CONUS IS
EXPECTED TO TRACK EASTWARD OVER THE CENTRAL PLAINS, WITH A LARGE
AREA OF HIGH PRESSURE IN THE UPPER MIDWEST THAT WILL KEEP DRY AND
QUIET WEATHER FOR THE REMAINDER OF THE WORK WEEK.
NORTH/NORTHEASTERLY WINDS WILL KEEP TEMPERATURES ON THE COOL SIDE
WITH HIGHS BOTH DAYS IN THE MID TO UPPER 70S. THE START OF THE
WEEKEND ALSO IS EXPECTED TO REMAIN DRY, THOUGH LOW LEVEL SOUTHERLY
FLOW WILL RETURN LATE SATURDAY INTO SUNDAY, WITH THE PASSAGE OF A
FEW MID-LEVEL TROUGHS INTO THE CENTRAL PLAINS THAT LOOK TO BRING A
RETURN TO SHOWERS AND POTENTIALLY STORMS BY SUNDAY, THOUGH THE
PARAMETER SPACE SEEMS TO REMAIN GENERALLY MORE FAVORABLE WEST
OF IOWA BUT WILL HAVE TO FURTHER REFINE ANY DETAILS IN THE
COMING DAYS AS MORE GUIDANCE CAPTURES THIS TIME PERIOD.
TEMPERATURES GENERALLY REMAIN IN THE UPPER 70S INTO THE NEXT
WORK WEEK, INCREASING SLIGHTLY INTO THE LOW 80S
TUESDAY/WEDNESDAY.
AVIATION /18Z TAFS THROUGH 18Z FRIDAY/
ISSUED AT 1232 PM CDT THU JUL 31 2025
WIDESPREAD HAZE FROM WILDFIRE SMOKE IS EXPECTED TO REMAIN
ACROSS THE STATE THROUGH THE REST OF THE DAY INTO FRIDAY, WHICH
WILL CONTINUE TO LEAD TO SLIGHTLY REDUCED VISIBILITIES AROUND
4-5 STATUTE MILES. OTHERWISE, AREAS OF HIGH CLOUDS WILL REMAIN
THIS AFTERNOON BEFORE GRADUALLY MOVING OUT. WINDS WILL GENERALLY
REMAIN LIGHT OUT OF THE NORTHEAST, WITH SOME OCCASIONAL GUSTS
UP TO 15 KNOTS AT TIMES. A SIGNAL IS IN PLACE FOR PATCHY FOG
ACROSS NORTHERN IOWA FRIDAY MORNING, ESPECIALLY NORTHEAST,
THOUGH CONFIDENCE IS LOW AT THIS TIME BUT WILL CONTINUE TO
CLOSELY MONITOR.
DMX WATCHES/WARNINGS/ADVISORIES
NONE.
UPDATE...HAGENHOFF
DISCUSSION...BURY
AVIATION...BURY
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