748  
FXUS63 KDMX 260834  
AFDDMX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DES MOINES IA  
334 AM CDT MON SEP 26 2016  
   
SHORT TERM
 
/TODAY/  
ISSUED AT 229 AM CDT MON SEP 26 2016  
 
MAIN UPPER SYSTEM WILL PASS FROM NORTHERN MINNESOTA INTO THE UPPER  
GREAT LAKES TODAY AS A CANADIAN AIRMASS PUSHES ACROSS MUCH OF THE  
MIDWEST INCLUDING IOWA. BROAD SCALE SUBSIDENCE WILL ENSURE SUNNY  
SKIES ACROSS THE AREA TODAY WITH THERMAL TROF BECOMING ESTABLISHED  
ACROSS WISCONSIN. CENTRAL IOWA WILL BE ON THE BACKSIDE OF THE  
THERMAL GRADIENT WITH TEMPERATURES BECOMING WARMER TO THE SOUTH AND  
WEST TODAY. OTHERWISE, DEEP MIXING IS EXPECTED TODAY WITH HIGHER  
WINDS ALOFT MAKING IT DOWN TO THE SURFACE, ESPECIALLY ACROSS THE  
NORTH. THEREFORE, ANTICIPATE BREEZY CONDITIONS BY MIDDAY WITH GUSTS  
OF 35 TO 40 MPH OCCURRING IN NORTHERN IOWA WEAKENING TO GUSTS OF 25  
MPH IN THE FAR SOUTH.  
   
LONG TERM
 
/TONIGHT THROUGH SUNDAY/  
ISSUED AT 229 AM CDT MON SEP 26 2016  
 
SUMMARY...REMAINS QUIET WITH REGARDS TO CONSEQUENTIAL WEATHER,  
THOUGH PERIODS OF WINDY CONDITIONS REMAIN FOR TUE AND WED.  
TEMPERATURES MOSTLY TO REMAIN ON THE COOL SIDE TO SEASONABLE FOR  
THIS TIME OF YEAR, WITH WED LOOKING COOLEST FOR THE WEEK. WIDESPREAD  
PRECIPITATION UNLIKELY TO RETURN BEFORE NEXT WEEK.  
 
TONIGHT THROUGH THURSDAY....THROUGH THIS PERIOD MODELS REMAIN IN  
GOOD CONSENSUS, WITH EURO REMAINING SLIGHTLY FURTHER WEST. A COUPLE  
OF CHANGES FROM PREVIOUS FORECASTS THOUGH, INCLUDING COOLER  
TEMPERATURES WED, INCREASED WINDS TUE/WED AND INCREASED CLOUD COVER  
WED. CHANGES PRIMARILY DRIVEN BY HEDGING TOWARDS THE EURO SOLUTION.  
OVER LAST COUPLE RUNS NAM/GFS/CANADIAN TRENDED TOWARD EURO, SO  
GROWING CONFIDENCE IN FURTHER HEDGING THAT DIRECTION. PV ANOMALIES  
RIDING AROUND THE LOW WILL DRIVE CLOUD COVER, WHICH MAY NOT BE HIGH  
ENOUGH STILL. SHOULD THAT OCCUR, ALREADY LOWERED HIGHS WED WOULD  
NEED TO BE LOWERED ANOTHER DEGREE OR TWO INTO THE LOW 60S. WINDS  
TUE/WED WILL BE AROUND 15KTS AT TIME WITH GUSTS IN EXCESS OF 20KTS,  
AGAIN DRIVEN BY PROXIMITY OF UPPER LOW AND SURFACE GRADIENT  
REFLECTION. SHOULD GOOD MIXING OCCUR, AT LEAST PARTIALLY CLOUD COVER  
DEPENDENT WED, GUSTS MAY APPROACH 25KTS AS FLOW IN THE 900-850MB  
LAYER AROUND 25KTS BOTH DAYS. TEMPERATURES PRIMARILY MID TO UPPER  
60S THROUGH THIS TIME FRAME.  
 
FRIDAY THROUGH SUNDAY....EURO AND GFS SOLUTIONS CONTINUE TO DIVERGE  
AT THIS POINT, WITH GFS TRENDING TOWARDS EURO. THAT SAID, LITTLE  
CONSEQUENCE OVERALL FOR THE REGION. SHOULD EURO COME TO FRUITION,  
POSSIBLE EAST SEES AN OPPORTUNITY FOR AN ISOLATED SHOWER, BUT  
CONFIDENCE REMAINS LOW THAT LOW WILL RETROGRADE WEST ENOUGH. WHILE  
MODELS DISAGREE WITH HANDLING OF THE CLOSED LOW, BOTH DIG IN A  
TROUGH INTO THE PACIFIC NORTHWEST DURING THE WEEKEND. RESULTING IN  
SW FLOW OVER IOWA AND OPPORTUNITY FOR SHOWERS EARLY NEXT WEEK.  
TEMPERATURES EEK INTO THE LOW 70S THROUGH THE WEEKEND.  
 

 
   
AVIATION
 
/FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT/  
ISSUED AT 1157 PM CDT SUN SEP 25 2016  
 
THERE IS A HIGH CONFIDENCE IN VFR CONDITIONS THROUGH THE PERIOD.  
MID/HIGH CLOUD SHIELD SHOULD EXIT SE IA SHORTLY GIVING WAY TO  
CLEAR SKIES INTO MONDAY. WNW WINDS WILL BECOME GUSTY DURING PEAK  
HEATING/MIXING OF THE AFTERNOON HOWEVER WITH SOME GUSTS 30KTS OR  
MORE NORTH.  
 

 
   
DMX WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  

 
 

 
 
SHORT TERM...COGIL  
LONG TERM...CURTIS  
AVIATION...SMALL  
 
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