158  
FXUS63 KARX 150249  
AFDARX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LA CROSSE WI  
949 PM CDT SAT SEP 14 2019  
   
SHORT TERM
 
(THIS EVENING THROUGH SUNDAY)  
ISSUED AT 245 PM CDT SAT SEP 14 2019  
 
AT 2 PM, SKIES WERE PARTLY TO MOSTLY CLOUDY ACROSS THE UPPER  
MISSISSIPPI RIVER VALLEY. SCATTERED SHOWERS AND ISOLATED STORMS  
HAVE DEVELOPED ALONG AND NORTH OF THE INTERSTATE 90 CORRIDOR. THE  
MOST ROBUST CONVECTION WAS NORTH OF THE TWIN CITIES. THIS LATTER  
PRECIPITATION IS LOCATED ON THE NOSE OF THE 850 MB JET. THIS JET  
IS BRINGING AN INCREASE IN THE MOISTURE AND INSTABILITY AHEAD OF  
A SHORTWAVE TROUGH OVER NORTHWEST MINNESOTA.  
 
ADDITIONAL STORMS WERE LOCATED ACROSS CENTRAL IOWA. THIS IS  
ASSOCIATED WITH A MCV THAT DEVELOPED OVERNIGHT IN EASTERN  
NEBRASKA. THIS CONVECTION WITH THIS SYSTEM WILL LIKELY REMAIN  
SOUTH OF THE AREA. TEMPERATURES WERE IN THE MID AND UPPER 60S  
NORTH OF INTERSTATE 94 AND IN THE 70S ELSEWHERE.  
 
FOR THIS EVENING, THE 14.12Z MODELS ARE IN GOOD AGREEMENT THAT  
THE NOSE OF THE 850 MB JET WILL MOVE INTO THE UPPER MISSISSIPPI  
VALLEY. AS THIS OCCURS, THE 0-1KM ML CAPES WILL CLIMB UP INTO 1500  
TO 2500 J/KG. SOUNDINGS CONTINUE TO SUGGEST THAT ANY SHOWERS AND  
STORMS WILL BE ELEVATED. THE 1-7 KM SHEAR IS VERY MARGINAL FOR THE  
POTENTIAL DEVELOPMENT OF ELEVATED SUPERCELLS. THE MAIN THREAT  
WOULD BE GUSTY WINDS AND HAIL. WITH PRECIPITABLE WATER VALUES  
BETWEEN 1.3 AND 1.8 INCHES, THESE STORMS WILL BE EFFICIENT RAIN  
PRODUCERS.  
 
THE CAMS ARE REALLY STRUGGLING WITH THE DEVELOPMENT AND  
THE PLACEMENT OF SHOWERS AND STORMS THIS AFTERNOON, SO CONFIDENCE  
IS NOT EXTREMELY HIGH ON HOW THIS IS EXACTLY GOING TO PLAY OUT  
THIS EVENING. OVERALL, THE EXPERIMENTAL ESRL HRRR SEEMS TO BE  
HANDLING THE PRECIPITATION THE BEST AT THE THIS TIME, SO TRENDED  
THE POPS TOWARD IT. IT WOULD SUGGEST THE CURRENT CONVECTION NORTH  
OF I-94 WOULD MOVE EAST ACROSS CLARK AND TAYLOR COUNTIES EARLY  
THIS EVENING. ADDITIONAL CONVECTION WOULD THEN DEVELOP ALONG AND  
SOUTH OF THE INTERSTATE 90 CORRIDOR DURING THE MID TO LATE  
EVENING.  
 
FOR OVERNIGHT, THE NOSE OF THE 850 MB JET WILL VEER AND MOVE EAST  
OF THE AREA. AS THIS OCCURS, EXPECT THE SHOWERS AND STORMS TO  
PROGRESSIVELY MOVE SOUTH AND EAST OUT OF OUR AREA. WITH THIS AREA  
BEING SO WET, IT WOULD NOT TAKE MUCH RAINFALL TO CAUSE ADDITIONAL  
FLOODING, SO KEPT THE FLASH FLOOD GOING. LOW TEMPERATURES TONIGHT  
WILL RANGE FROM THE MID 50S TO MID 60S.  
 
ON SUNDAY, HIGH PRESSURE WILL GRADUALLY BUILD ACROSS THE REGION.  
SKIES WILL GRADUALLY CLEAR FROM THE WEST. HIGH TEMPERATURES WILL  
RANGE FROM THE MID 70S TO MID 80S.  
   
LONG TERM
 
(SUNDAY NIGHT THROUGH SATURDAY)  
ISSUED AT 245 PM CDT SAT SEP 14 2019  
 
FROM MONDAY INTO TUESDAY NIGHT, TEMPERATURES LOOK TO BE WELL ABOVE  
NORMAL. 850 MB TEMPERATURES ARE RUNNING 1 TO 2 STANDARD  
DEVIATIONS ABOVE NORMAL. DUE TO THIS, WENT A COUPLE OF DEGREES  
ABOVE THE MOS.  
 
FROM TUESDAY INTO WEDNESDAY, THERE CONTINUES TO A LOT OF  
UNCERTAINTY ON THE EASTERN EXTENT OF A MESOSCALE CONVECTIVE  
COMPLEX. THE GFS WOULD MOVE IT THROUGH OUR AREA. THE ECMWF WOULD  
MOVE IT NORTHWEST OF OUR AREA FROM TUESDAY NIGHT INTO WEDNESDAY.  
MEANWHILE, THE CANADIAN KEEPS MUCH OF ITS PRECIPITATION NORTH OF  
INTERSTATE 90. DUE TO THESE UNCERTAINTIES, MADE LITTLE CHANGE TO  
THE NBM PRECIPITATION CHANCES.  
 

 
   
AVIATION
 
(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)  
ISSUED AT 949 PM CDT SAT SEP 14 2019  
 
MAIN AVIATION CONCERNS ARE ON SCATTERED SHOWERS AND STORMS TONIGHT  
AND MVFR TO IFR STRATUS LATE TONIGHT INTO SUNDAY MORNING.  
SCATTERED SHOWERS AND STORMS WILL MOVE ACROSS THE AREA TONIGHT  
WITH MOST OF THIS ACTIVITY STAYING SOUTH OF THE TAF SITES. THEN  
GUIDANCE IS SUGGESTING LOW STRATUS DEVELOPS ACROSS THE AREA MAINLY  
AFTER 09Z. CEILINGS ARE EXPECTED TO FALL TO AROUND 600 FT AT KRST  
BY 11Z AND TO AROUND 1500 FT AT KLSE AROUND 11Z. HIGH PRESSURE  
THEN BUILDS INTO THE AREA LATE SUNDAY MORNING INTO SUNDAY  
AFTERNOON WITH A RETURN TO VFR CONDITIONS.  
 

 
   
HYDROLOGY
 
TONIGHT  
ISSUED AT 354 PM CDT SAT SEP 14 2019  
 
MODERATE TO STRONG 850 MB MOISTURE CONVERGENCE WILL MOVE INTO THE  
AREA THIS EVENING AND THEN MOVE QUICKLY OUT OF THE AREA BETWEEN  
15.09Z AND 15.12Z. WITH PRECIPTABLE WATER VALUES OF 1.3 TO 1.8  
INCHES, THESE STORMS WILL BE CAPABLE OF PRODUCING HEAVY RAIN.  
RAINFALL AMOUNTS WILL RANGE FROM A HALF TO 1 INCH, BUT REPEAT  
THUNDERSTORMS OVER LOCALIZED AREAS COULD PRODUCE HIGHER AMOUNTS.  
 
WITH THE RECENT RAINFALL, SOILS ARE SATURATED, AND CREEKS AND RIVERS  
ARE ALREADY RUNNING HIGHER THAN NORMAL. THIS MEANS IT WILL TAKE LESS  
RAINFALL TO CAUSE MUDSLIDES AND FLOODING.  
 

 
   
ARX WATCHES/WARNINGS/ADVISORIES
 
 
WI...FLASH FLOOD WATCH UNTIL 7 AM CDT SUNDAY FOR WIZ053>055-061.  
 
MN...FLASH FLOOD WATCH UNTIL 7 AM CDT SUNDAY FOR MNZ086-087-094>096.  
 
IA...FLASH FLOOD WATCH UNTIL 7 AM CDT SUNDAY FOR IAZ008>011-018-019-  
029-030.  
 

 
 

 
 
SHORT TERM...BOYNE  
LONG TERM...BOYNE  
AVIATION...WETENKAMP  
HYDROLOGY...BOYNE  
 
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