000 
FXUS63 KFSD 010826
AFDFSD

AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA 
NATIONAL WEATHER SERVICE SIOUX FALLS SD
330 AM CDT TUE MAR 31 2009

.DISCUSSION...
STG UPPER AND SFC LOW WILL CONT TO PULL SLWLY NEWD AWAY FROM FCST 
AREA TDA. CURRENT FLRYS NERN HALF OF AREA WITH A FEW AREAS OF 
MINIMALLY MEASURABLE SNOW SHUD DCRS TO JUST SCT FLRYS BY 7AM/12Z AND 
SLWLY DECREASE DURG THIS MRNG. WILL CONT TO LEAVE OUT FOR THIS AFTN 
AS CLDS CONT TO DCRS. SLOW DCRS IN WINDS WILL BE STALLED BY SOME 
DAYTIME MIXING THEN WINDS WILL DROP OFF MORE BY ERY EVE. MET HI 
TEMPS DONT LOOK TOO BAD AND ARE MUCH PREFERRED OVER THE TOO WARM 
MAV...EVEN OVER NON SNOW COVERED AREAS. THIS IS WITHOUT ADDING IN 
THE COOLING FACTOR OF LINGERING WINDS.

TNGT THRU THU NGT SHUD BE DRY AND CLEAR TO PTCLDY AS NEXT SYS STAYS 
WELL S OF AREA AND WEAK HIGH PRES WEDGES INTO AND MOVES EWD OVER 
AREA. AGAIN THE COOLER MET TEMPS PREFERRED OVER MAV...APRIL HEATING 
NOTWITHSTANDING.

MAJOR WET SYS SHUD ARRIVE FOR THE WEEKEND AND EVENTUAL HI POPS 
CENTERED SAT AND SAT NGT LOOK GOOD. SOME DOUBT ON HOW FAST PCPN WILL 
SPREAD INTO AREA WELL AHD OF SYS FRI AND FRI NGT BUT WITH THE 
POTENTIAL THERE WILL NOT CHANGE THE CHC POPS WE HAVE OVER AREA BY 
FRI NGT. IN FACT NO BIG CHANGES TO THE WEEKEND FCST WITH LOTS OF 
QUESTONS LEFT ON DETAILS SUCH AS PCPN TYPE AND EXACT TIMING. HWVR 
MODELS ARE IN UNUSUALLY GOOD CONSENSUS THAT THERE WILL BE A MAJOR 
PCPN EVENT AFFECTING FCST AREA WITH THE HIGHEST THREAT AND WETTEST 
POTENTIAL ACROS THE SRN FCST AREA. BOTH CANADIAN AND ECMWF THREATEN 
2 INCHES OVER SRN FCST AREA WITH THE GFS VERY CLOSE BEHIND. THE 
DOUBT ON PCPN TYPE SHUD SLWLY DECREASE DURG THE WEEKEND IN FAVOR OF 
SNOW. DRY SLOTTING A QUESTION BUT THIS AND EVENTUAL PCPN TYPE LIKELY 
TO BE LESS OF AN ISSUE WITH THIS SYS THAN THE ONE JUST PAST AS THIS 
NEXT ONE SHUD NOT TURN NWD/NNEWD INTO AREA AS THE ONE YESTERDAY DID.

DRY AND COOL FOR NEXT MON/TUE LOOKS GOOD AS COOL SFC RIDGE BUILDS 
INTO FCST AREA BHND SYS.

&&

.AVIATION...
MVFR CIGS AT HON AND FSD AT 08Z WL BECOME VFR BY 15Z. VFR CONDITIONS 
EXPECTED AT SUX.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...

SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.

&&

$$
WILLIAMS