992  
FXUS63 KDMX 172342  
AFDDMX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DES MOINES IA  
642 PM CDT SAT OCT 17 2026  
 
...UPDATED FOR THE 00Z AVIATION DISCUSSION...  
   
KEY MESSAGES  
 
- THE FORECAST IS DRY THROUGH THE COMING WORK WEEK WITH SLOWLY  
WARMING TEMPERATURES.  
 
- A BIT BREEZY THROUGH SUNDAY, THOUGH NOT NEARLY AS MUCH AS IT  
WAS ON SATURDAY.  
 
- RAIN CHANCES AND MORE CHANGEABLE WEATHER CONDITIONS MAY RETURN  
NEXT WEEKEND, BUT FORECAST DETAILS ARE STILL IN FLUX AT THIS  
RANGE.  
 
 
   
SHORT TERM /THROUGH MONDAY NIGHT/  
 
ISSUED AT 128 PM CDT SAT OCT 17 2026  
 
WE GOT OFF TO A COOL START THIS MORNING, WITH MUCH OF OUR  
SERVICE AREA EXPERIENCING THE FIRST FREEZE OF THE SEASON. A FEW  
STATIONS SUCH AS THE DES MOINES AIRPORT AND LAMONI REMAINED JUST  
ABOVE FREEZING AROUND 34-35, BUT MOST OTHER STATIONS FELL TO 32  
OR BELOW, AND IN MOST OF OUR NORTHERN AND WESTERN COUNTIES THE  
TEMPERATURE FELL BELOW 30 DEGREES.  
 
THE SURFACE RIDGE THAT WAS DRAPED ACROSS MUCH OF IOWA LAST  
NIGHT IS SLIDING SOUTHEASTWARD TODAY, AND WILL RESIDE ROUGHLY  
ALONG OR JUST NORTH OF THE OHIO RIVER VALLEY BY SUNDAY MORNING.  
MEANWHILE, A BROAD LOW PRESSURE TROUGH IS FORMING ALONG THE LEE  
OF THE ROCKIES, AND THE PRESSURE GRADIENT BETWEEN THE TROUGH AND  
THE RIDGE WILL BE LOCATED MORE ACROSS OUR AREA FROM THIS  
AFTERNOON THROUGH SUNDAY AFTERNOON. THIS WILL RESULT IN FRESH  
SOUTH TO SOUTHWEST BREEZES DURING THAT TIME. TEMPERATURES WILL  
REMAIN A BIT BELOW SEASONAL NORMALS THIS AFTERNOON, COMBINING  
WITH THE BREEZES TO KEEP THINGS A BIT CHILLY OUTSIDE DESPITE THE  
RESPLENDENT SUNSHINE. THE BREEZE WILL THEN HELP TEMPERATURES  
STAY UP TONIGHT, WITH LOWS AROUND SUNRISE SUNDAY MORE IN THE  
LOWER 40S OR SO THROUGHOUT OUR FORECAST AREA. HOWEVER, ANY MORE  
SHELTERED SPOTS WHERE WINDS TO LIGHT OVERNIGHT MAY COOL INTO THE  
MID/UPPER 30S. ON SUNDAY TEMPERATURES WILL REBOUND DUE TO  
AIRMASS MODIFICATION, WITH HIGHS GENERALLY IN THE MID 60S MAKING  
FOR A GLORIOUS AUTUMN DAY.  
 
FROM SUNDAY NIGHT THROUGH MONDAY NIGHT THE SURFACE PATTERN WILL  
LOOSEN UP, RESULTING IN LIGHTER WINDS. A BROAD HIGH PRESSURE  
AREA WILL PERSIST TO OUR EAST, ROUGHLY OVER THE GREAT LAKES  
REGION, WITH LIGHT SOUTHEASTERLY BREEZES IN OUR AREA ENTRAINING  
DRY AIR OUT OF THAT RIDGE. DRY, CLEAR CONDITIONS WITH LIGHT  
WINDS WILL SUPPORT A CONTINUED WARMING TREND DURING THE DAY, AND  
GOOD COOLING CONDITIONS OVERNIGHT BUT AGAIN WITH A SLOW  
MODIFICATION TREND CONTINUING. NBM TEMPERATURES IN THIS REGIME,  
FROM SUNDAY THROUGH MONDAY NIGHT, ARE A BIT TOO LOW DURING THE  
DAY AND A BIT TOO HIGH DURING THE NIGHT AS IT APPEARS TO BE  
OVERDONE WITH ITS SURFACE HUMIDITY/DEWPOINTS. HAVE THUS  
CONTINUED THE TREND OF BUMPING UP DAYTIME TEMPS AND BUMPING DOWN  
NIGHTTIME TEMPS. THE RESULT IS MONDAY AFTERNOON HIGHS  
APPROACHING 70 DEGREES IN OUR SOUTHEASTERN COUNTIES, WITH SUNDAY  
NIGHT AND MONDAY NIGHT LOWS GENERALLY IN THE UPPER 30S TO MID  
40S. ADDITIONAL FREEZES ARE NOT ANTICIPATED IN THE NEAR FUTURE.  
 
 
   
LONG TERM /TUESDAY THROUGH SATURDAY/  
 
ISSUED AT 128 PM CDT SAT OCT 17 2026  
 
BY TUESDAY MORNING, A BROAD 500 MB HIGH PRESSURE RIDGE WILL BE  
LOCATED OVER MOST OF THE CENTRAL AND EASTERN U.S. HOWEVER, A  
WEAK SHORTWAVE WILL BE MOVING OFF THE ROCKIES AND OVER THE HIGH  
PLAINS. THIS FEATURE WILL PASS SLOWLY NEAR IOWA ON TUESDAY INTO  
WEDNESDAY, BRINGING SOME MID/HIGH LEVEL CLOUDS ACROSS THE REGION  
DURING THAT TIME. A FEW MODEL SOLUTIONS EVEN ATTEMPT TO SPIT  
OUT LIGHT RAINFALL, HOWEVER, FORECAST SOUNDINGS INDICATE  
SUBSTANTIAL DRY AIR IN THE LOWER/NEAR-SURFACE LEVELS WITH FLOW  
OUT OF THE GREAT LAKES RIDGE, WHICH SHOULD PRECLUDE ANY  
MEANINGFUL CHANCES OF PRECIPITATION. MEANWHILE, DESPITE SOME  
INCREASE IN CLOUD COVER, AIRMASS MODIFICATION SHOULD ALLOW FOR  
CONTINUATION OF A SLOW WARMING TREND WITH TEMPERATURES PEAKING  
IN THE LOWER 70S OR SO ON WEDNESDAY AFTERNOON.  
 
FROM LATE WEDNESDAY INTO FRIDAY A MORE PRONOUNCED 500 MB RIDGE  
WILL BUILD OVER THE CENTRAL U.S., INCLUDING IOWA, SUPPORTING  
CONTINUED DRY WEATHER AND SLOW WARMING. HIGHS IN THE 70S ARE  
FORECAST BOTH THURSDAY AND FRIDAY. EVENTUALLY, BY THE END OF THE  
WEEK, A DEEP 500 MB TROUGH WILL MOVE INTO THE WESTERN U.S.  
ROCKIES AND BRING A RETURN OF MORE CHANGEABLE WEATHER AND SOME  
RAIN CHANCES BY NEXT WEEKEND. ANY DETAILS OF TIMING/LOCATION OF  
RAIN CHANCES AND OTHER SENSIBLE WEATHER FIELDS ARE STILL IN FLUX  
AT THIS RANGE, BUT WILL STEADILY COME INTO BETTER FOCUS AS THIS  
WEEK PROGRESSES.  
 
 
   
AVIATION /00Z TAFS THROUGH 00Z MONDAY/  
 
ISSUED AT 639 PM CDT SAT OCT 17 2026  
 
VFR CONDITIONS TO PREVAIL THROUGH THE PERIOD. LLWS IS MOST  
LIKELY AT KFOD AND KMCW, LESS LIKELY TO THE SOUTHEAST. KMCW WILL  
HAVE WIND GUSTS RESUME AFTER 05Z, LASTING FOR THE REMAINDER OF  
THE PERIOD. SOUTHWEST WINDS WILL PREVAIL TOMORROW WITH GUSTS  
AROUND 20KTS COMMON.  
 
 
   
DMX WATCHES/WARNINGS/ADVISORIES  
 
NONE.  
 
 
 
 
 
SHORT TERM...LEE  
LONG TERM...LEE  
AVIATION...JIMENEZ  
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