333  
FXUS63 KMPX 250343  
AFDMPX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN  
1043 PM CDT FRI MAR 24 2017  
   
SHORT TERM
 
(THIS EVENING THROUGH SATURDAY)  
ISSUED AT 341 PM CDT FRI MAR 24 2017  
 
TYPICAL MARCH WEATHER UNDERWAY HERE WITH ALL THE SUMMER  
TEMPERATURES TO THE SOUTHEAST. STRATUS AND NORTHERLY FLOW HAVE  
KEPT TEMPS ONLY IN THE 30S AND 40S, BUT CHICAGO MANAGED TO REACH  
THE LOW 80S SOUTH OF THE FRONT. DRIER AIR WILL WORK INTO WESTERN  
MN THIS EVENING AND CLOUDS SHOULD CLEAR NICELY, WHICH IS ALREADY  
EVIDENT ON SATELLITE. THE PRECIP BAND HAS WEAKENED AND SHIFTED  
SOUTHEAST BUT THE UPPER LOW ACROSS THE SOUTHERN PLAINS WILL EJECT  
NORTHEASTWARD TO THE MID MISSISSIPPI VALLEY SATURDAY/SATURDAY  
NIGHT WHICH WILL BRING THE CLOUDS AND PRECIP BAND BACK  
NORTHWESTWARD. AMOUNTS WILL BE LIGHT AND THE PRECIP SHOULD BE  
CONFINED TO SOUTHEAST OF A FAIRMONT TO EAU CLAIRE LINE THROUGH THE  
DAY.  
   
LONG TERM
 
(SATURDAY NIGHT THROUGH FRIDAY)  
ISSUED AT 341 PM CDT FRI MAR 24 2017  
 
THE WEATHER PATTERN THAT WE ARE CURRENTLY IN IS DIFFICULT TO  
PREDICT. THAT IS THE BOTTOM LINE, SO THOUGHT IT BEST TO TEMPER  
EXPECTATIONS AND ACKNOWLEDGE THAT THERE WILL BE LITTLE CHANGE IN  
THE FORECAST AND NOT ANTICIPATING ANY DRASTIC UPTICK IN CONFIDENCE  
UNTIL THIS HIGHLY AMPLIFIED, SPLIT-FLOW PATTERN CHANGES. THE  
REASON BEING, AMPLIFIED WAVES EVENTUALLY END UP BREAKING AND  
GETTING CUT OFF FROM THE MAIN FLOW. PREDICTING A CUT-OFF WAVES  
MOVEMENT IS DIFFICULT, ESPECIALLY WHEN THERE ARE MULTIPLE WAVES  
THAT INTERACT WITH EACH OTHER.  
 
WITHIN THESE UPPER LEVEL LOWS ARE AREAS OF ENHANCED VORTICITY WHICH  
END UP PRODUCING PRECIPITATION. FOR EXAMPLE, ON SATURDAY NIGHT  
MODELS INDICATE A BAND OF LIGHT RAIN LIFTING NORTHWARD, BUT THE  
POSITIVE VORTICITY ADVECTION IS WEAK, THE PRECIP IS LIGHT, AND THE  
CONFIDENCE IN RECEIVING MEASURABLE RAINFALL IS LOW, SO ONLY HAVE A  
25 TO 35 PERCENT CHANCE OF RAIN THROUGH SUNDAY. ON MONDAY A NORTHERN  
STREAM WAVE WILL MOVE THROUGH AND SUBSIDENCE ON THE BACK SIDE WILL  
BRING AN END TO THE PRECIPITATION CHANCES, BUT FORECAST SOUNDINGS  
SHOW RESIDUAL BOUNDARY LAYER MOISTURE, SO SHOULD SEE INCREASING  
CLOUDS DRIVEN BY DAYTIME HEATING.  
 
TUESDAY WILL END UP BEING THE SUNNIEST DAY OF THE FORECAST WITH  
HIGHS IN THE LOWER 50S EXPECTED. ON WEDNESDAY ANOTHER OCCLUDED  
CYCLONE OVER THE SOUTHERN PLAINS WILL SPREAD MID LEVEL MOISTURE AND  
CLOUDS OVER THE UPPER MIDWEST. CONFIDENCE TAPERS OFF CONSIDERABLY  
AFTER WEDNESDAY, SO CONTINUED WITH THE BLENDED GUIDANCE AND SLIGHT  
CHANCES FOR PRECIPITATION. ONE THING IS HIGHLY LIKELY, AND THAT  
IS THE MONTH OF MARCH WILL ONCE AGAIN BE ABOVE NORMAL AT MSP AND  
STC, POSSIBLY AT EAU AS WELL.  
 

 
   
AVIATION
 
(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)  
ISSUED AT 1043 PM CDT FRI MAR 24 2017  
 
WE OFFICIALLY HAVE STRATUS TRAPPED BENEATH AN INVERSION AND WITH  
THE MOISTURE ASSOCIATED WITH THE RAIN FIELD ACROSS IA INTO WI  
COMING BACK NORTHWEST DURING THE DAY SATURDAY, SEE NO REASON WHY  
WE DON'T KEEP THE CLOUDS GOING THROUGH THIS PERIOD. THE LONE  
EXCEPTION WOULD BE AT AXN, WHOSE POSITION NEAR THE SURFACE RIDGE  
AXIS MAY ALLOW THE CLOUDS TO MIX OUT THERE, SIMILAR TO WHAT WE SAW  
FRIDAY. FOR EVERYONE ELSE, CIGS WILL BE PRETTY STEADY THROUGH THE  
DAY, WITH A BIT MORE OF A LOWERING POSSIBLE SATURDAY NIGHT AS  
WHAT IS CURRENTLY TO OUR SOUTHEAST HEADS THIS WAY. LIKE THE IDEA  
OF THE GFS WITH A BAND OF -RA WORKING BACK NORTHWEST INTO  
SOUTHEAST MN AFTER 18Z, REACHING EAU BETWEEN 1Z AND 3Z AND MSP  
BETWEEN 4Z AND 7Z. RAIN WILL BE PRETTY LIGHT, BUT MAY BE ENOUGH TO  
BUMP VIS DOWN INTO THE MVFR CATEGORY WHILE PRECIP IS FALLING.  
 
KMSP...CLOUDS ARE HERE TO STAY, LIKELY UNTIL SUNDAY NIGHT OR  
MONDAY MORNING. FOLLOWED THE IDEA OF THE 00Z GFS FOR BRINGING A  
BAND OF -RA INTO THE TWIN CITIES AROUND 6Z. THIS WILL BE ON A  
WEAKENING TREND, BUT ENOUGH SUPPORT FROM OTHER HI-RES MODELS ON  
THIS GFS SOLUTION TO INCLUDE SOME LIGHT RAIN TO END THE TAF  
PERIOD.  
 
/OUTLOOK FOR KMSP/  
SUN...MVFR. CHC -RA. WIND NNE 5 KTS.  
MON...CHC MVFR EARLY. WIND N 5 KTS.  
TUE...VFR. WIND NE 5 KTS.  
 

 
   
MPX WATCHES/WARNINGS/ADVISORIES
 
 
WI...NONE.  
MN...NONE.  

 
 

 
 
SHORT TERM...BORGHOFF  
LONG TERM...JRB  
AVIATION...MPG  
 
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