741  
FXUS63 KDVN 210655  
AFDDVN  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE QUAD CITIES IA IL  
155 AM CDT TUE JUL 21 2026  
   
KEY MESSAGES
 
 
- HUMID CONDITIONS WILL CONTINUE TODAY UNTIL A SECONDARY FRONT  
MOVES THROUGH LATE THIS AFTERNOON. NORTHWEST WINDS GUSTING UP  
TO 30 MPH SHOULD PUSH MOST OF THE WILDFIRE SMOKE OUT OF THE  
AREA.  
 
- MUCH COOLER AND LESS HUMID CONDITIONS WILL BE SEEN THE  
REMAINDER OF THE WORK WEEK BEFORE HEAT AND HUMIDITY RETURN FOR  
THE WEEKEND.  
 
- MAINLY DRY CONDITIONS OVER THE NEXT 7 DAYS AS RAIN CHANCES ARE  
QUITE LOW.  
 

 
   
SHORT TERM /THROUGH TONIGHT/
 
 
ISSUED AT 153 AM CDT TUE JUL 21 2026  
 
THROUGH SUNRISE, SCATTERED SHOWERS AND POSSIBLY A THUNDERSTORM WILL  
BE SEEN AS THE COLD FRONT SWEEPS THROUGH THE AREA.  
 
WINDY, COOLER BUT HUMID CONDITIONS WILL BE SEEN ACROSS THE AREA  
DURING THE DAYLIGHT HOURS. DEEP MIXING OCCURRING BEHIND THE COLD  
FRONT SHOULD ALLOW WINDS TO GUST UP TO 30 MPH. THE STRONG NORTHWEST  
WINDS SHOULD PUSH MOST OF THE WILDFIRE SMOKE OUT OF THE AREA.  
 
HUMIDITY LEVELS WILL BEGIN DROPPING AROUND SUNSET AS A SECONDARY  
FRONT MOVES THROUGH THE AREA. WINDS WILL ALSO DIMINISH AS THE  
BOUNDARY LAYER DECOUPLES.  
 

 
   
LONG TERM /WEDNESDAY THROUGH MONDAY/
 
 
ISSUED AT 153 AM CDT TUE JUL 21 2026  
 
WEDNESDAY THROUGH THURSDAY NIGHT  
ASSESSMENT...A CERTAINTY OF COOLER AND LESS HUMID CONDITIONS  
 
WEDNESDAY AND THURSDAY WILL BE BANNER DAYS WITH COOLER TEMPERATURES  
AND DEW POINTS IN THE 50S.  
 
THE MODELS HAVE TRENDED STRONGER WITH THE HIGH OVER THE WESTERN  
GREAT LAKES WHICH HAS NOW RESULTED IN THURSDAY NIGHT BEING DRY. THIS  
STRONGER HIGH HAS RAMIFICATIONS FOR RAIN CHANCES FRIDAY  
 
FRIDAY  
ASSESSMENT...LOW (<20%) CONFIDENCE ON RAIN CHANCES  
 
THE GLOBAL MODELS HAVE NOW CONFINED ANY RAIN CHANCES ON FRIDAY TO  
THE MORNING HOURS. DPROG/DT SHOWS THE SYSTEM FURTHER SOUTH THAN  
YESTERDAY WHICH IS A RESULT OF THE HIGH IN THE WESTERN GREAT LAKES  
BEING STRONGER.  
 
THE DETERMINISTIC MODEL RUNS (SAVE THE GFS) ARE DRY FOR FRIDAY.  
HOWEVER, THERE ARE SOME ENSEMBLE MEMBERS FROM EACH GLOBAL MODEL THAT  
HAVE RAIN CHANCES ACROSS THE AREA FRIDAY MORNING.  
 
WITH THE HIGH STRONGER AND THE SYSTEM FURTHER SOUTH IN MISSOURI, THE  
PROSPECTS FOR RAIN ARE NOT GOOD. A REVIEW OF THE INTEGRATED VAPOR  
TRANSPORT SHOWS THE STRONGEST VALUES RUN FROM OKLAHOMA INTO  
SOUTHEAST KANSAS AND SOUTHERN MISSOURI. THUS WHILE THE MODEL  
CONSENSUS CURRENTLY HAS 15-35 PERCENT RAIN CHANCES FRIDAY MORNING, I  
SUSPECT THESE VALUES WILL SLOWLY DROP OVER THE NEXT TWO DAYS.  
 
FRIDAY NIGHT THROUGH MONDAY  
ASSESSMENT...MEDIUM TO HIGH (60-80%) CONFIDENCE OF RISING HUMIDITY  
LEVELS  
 
RETURN FLOW DEVELOPS ACROSS THE MIDWEST STARTING FRIDAY NIGHT AND  
CONTINUES THROUGH THE WEEKEND AS THE HEAT DOME BUILDS NORTH INTO THE  
PLAINS. DEW POINTS WILL SLOWLY INCREASE BACK INTO THE LOW TO MID 60S  
ON SATURDAY WITH MID AND UPPER 60 DEW POINTS SUNDAY INTO MONDAY. THE  
COMBINATION OF RISING TEMPERATURES AND DEW POINTS WILL EVENTUALLY  
PUSH HEAT INDICES INTO THE 90S AGAIN.  
 

 
   
AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/
 
 
ISSUED AT 1212 AM CDT TUE JUL 21 2026  
 
COLD FRONT TO SWEEP THROUGH EASTERN IOWA AND NORTHERN ILLINOIS  
THROUGH 15Z/21. PRIOR TO 12Z/21 SHRA OR EVEN A TSRA WILL BE  
POSSIBLE BUT COVERAGE WILL BE 10-30 PERCENT. AFTER 15Z/21 DEEP  
MIXING WILL ALLOW WIND GUSTS UP TO 25 KNOTS TO OCCUR. THE WINDS  
WILL SUBSIDE WITH SUNSET AS THE BOUNDARY LAYER STABILIZES AND  
HIGH PRESSURE BUILDS INTO THE MIDWEST.  
 

 
   
DVN WATCHES/WARNINGS/ADVISORIES
 
 
IA...NONE.  
IL...NONE.  
MO...NONE.  
 

 
 

 
 
SHORT TERM...08  
LONG TERM...08  
AVIATION...08  
 
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