933  
FXUS63 KDVN 270803  
AFDDVN  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE QUAD CITIES IA IL  
303 AM CDT MON MAR 27 2017  
   
SYNOPSIS
 
 
ISSUED AT 301 AM CDT MON MAR 27 2017  
 
STRATUS. WHILE SOME UPPER AIR FEATURES HAVE MOVED IN THE PAST 24  
HOURS, THE LOW CLOUDS HAVE NOT, AND THAT IS BY FAR THE MAIN IMPACT  
ON WEATHER OVER THE UPPER MIDWEST THIS MORNING. LIGHT RAIN SHOWERS  
ARE SPREADING NORTHEAST FROM MISSOURI AND KANSAS, AND HAVE REACHED  
FAR SOUTHERN IOWA AS OF 2 AM. MOST OF THIS ACTIVITY IS VERY LIGHT.  
 

 
   
SHORT TERM
 
(TODAY AND TONIGHT)  
ISSUED AT 301 AM CDT MON MAR 27 2017  
 
RAINS CONTINUE TO LOOK ON TRACK FOR THE SOUTHERN 1/2 OF THE CWA OR  
SO TODAY. NEAR INTERSTATE 80 IS THE CUT OFF, AND REPRESENTS A SHARP  
GRADIENT FROM A DRY FORECAST TO RATHER HIGH POPS DUE TO THE  
STRATIFORM NATURE OF THE LIGHT RAIN. THE MAIN BOUGHT OF FORCING  
TODAY WILL BE TIMED THROUGH ABOUT LATE MORNING. A WETTING LIGHT RAIN  
IS EXPECTED, ESPECIALLY ALONG AND SOUTH OF HIGHWAY 34 IN IOWA AND  
WEST CENTRAL ILLINOIS/NORTHEAST MISSOURI, AND THIS WILL BE HANDLED  
WITH A PERIOD OF CATEGORICAL POPS. RAINFALL AMOUNTS SHOULD BE ON  
THE ORDER OF 0.01 TO 0.15 IN MOST SPOTS, WITH NEAR 0.20 IN THE FAR  
SOUTH. THE UNRELENTING CLOUD COVER, LIGHT NORTH WINDS, AND LIGHT  
RAIN WILL SERVE TO HOLD TEMPERATURES DOWN AGAIN, AND I HAVE GONE  
SLIGHTLY UNDER THE GUIDANCE BLEND FOR HIGHS TODAY, IN THE LOWER TO  
MID 50S. TONIGHT, WHILE DRY WEATHER WILL BE EXPECTED, THE LOW CLOUDS  
SHOULD RULE THE NIGHT AGAIN, AND LOWS SHOULD ONLY FALL TO THE LOWER  
TO MID 40S IN MOST AREAS, MUCH LIKE THE CURRENT PERIOD.  
   
LONG TERM
 
(TUESDAY THROUGH SUNDAY)  
ISSUED AT 301 AM CDT MON MAR 27 2017  
 
ACTIVE FLOW REGIME REMAINS FOR THE LONG TERM PERIOD WITH A FEW  
CHANCES FOR PRECIP THROUGH THE PERIOD. MAIN FORECAST CONCERN WILL  
BE AGREEMENT BETWEEN GUIDANCE ON FORECAST SOLUTIONS AND SUBSEQUENT  
CONFIDENCE IN THE LONG TERM FORECAST.  
 
AT THE BEGINNING OF THE LONG TERM, ZONAL TO SW FLOW WILL BRING IN  
THE NEXT WARM AIR ADVECTION WING OF PRECIP. GUIDANCE REMAINS  
DIFFERENT IN PLACEMENT IN THE UPPER LEVEL WAVES. THIS MEANS THAT  
PRECIP FOR OVERNIGHT TUESDAY INTO WEDNESDAY SHOWS DIFFERENT QPF  
PLACEMENT AND AMOUNTS. THE CHANCE FOR MEASURABLE PRECIP SEEMS  
LIKELY, HOWEVER TOTAL MAGNITUDE OF THIS PRECIP IS STILL HARD TO  
DETERMINE WITH THE GUIDANCE DIFFERING FROM A QUARTER OF AN INCH AREA  
WIDE TO NEAR AN INCH IN OTHER MODEL GUIDANCE. THE CHANCE FOR PRECIP  
WILL BE SPREAD OVER A FEW DAYS AT LEAST INTO THURSDAY AS ANOTHER  
SURFACE LOW TRANSVERSES SOUTH OF THE CWA. OVERALL CONFIDENCE IN  
SYSTEM IS HIGH, WITH TOTAL QPF AMOUNT CONFIDENCE MEDIUM.  
 
A SHORT REPRIEVE FOR FRIDAY FROM PRECIP BEFORE ANOTHER UPPER LEVEL  
LOW WILL MOVE INTO THE CENTRAL US GREAT PLAINS. ANOTHER SURFACE LOW  
WILL TRACK SOUTH OF THE AREA THROUGH MO AND INTO CENTRAL IL. EVEN  
THOUGHT GUIDANCE IS IN GOOD AGREEMENT IN THE PLACEMENT OF THIS LOW  
AND WAVE, I HAVE LOW CONFIDENCE IN THIS SOLUTION AS THE ENERGY FOR  
THE SYSTEM IS OFF SHORE AND THERE ARE STILL TWO LOWS TO MOVE THROUGH  
THE AREA BEFORE THIS ONE.  
 
PAST THE WEEKEND, A WAVE TRAIN OF LOWS CONTINUES. THERE WILL BE  
ANOTHER CHANCE FOR PRECIP AT THE END OF THE PERIOD. CONFIDENCE IN  
THESE SOLUTIONS ARE LOW, THAT SAID, THE PATTERN FAVORS RAIN AND MORE  
CHANCES OF MEASURABLE PRECIP.  
 

 
   
AVIATION
 
(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)  
ISSUED AT 1153 PM CDT SUN MAR 26 2017  
 
PERIOD OF IFR/LIFR CEILINGS OVERNIGHT THROUGH EARLY MONDAY MORNING  
BEFORE IMPROVEMENT TO MVFR BY MIDDAY/EARLY AFTN.  
 
FOG NOT EXPECTED TO BE AS DENSE AS LAST NIGHT OR THIS MORNING WITH  
LESS OF A SFC CONVERGENCE ZONE AND LIGHT NW WINDS CONTINUING.  
OTHERWISE, PERIODS OF DRIZZLE WITH MVFR/IFR FOG ARE INCLUDED IN  
TAFS. AT KBRL/KMLI, THERE IS A BETTER CHANCE FOR LIGHT RAIN SHOWERS  
MONDAY MORNING INTO THE EARLY AFTN. NOW HAVE HIGHER CONFIDENCE IN  
THIS OCCURRING, SO MENTIONED -SHRA AT BOTH TERMINALS. UTTECH  
 

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

 
 

 
 
SYNOPSIS...ERVIN  
SHORT TERM...ERVIN  
LONG TERM...GIBBS  
AVIATION...UTTECH  
 
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