FXUS63 KFSD 012107
AFDFSD

AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA 
NATIONAL WEATHER SERVICE SIOUX FALLS SD
310 PM CST TUE DEC 1 2009

.DISCUSSION...
STRONGEST OF WINDS TRAILING SURFACE FRONT BY A COUPLE OF HOURS... 
WITH STRONGEST OF WINDS SEEMINGLY LASTING FOR 2-3 HOURS. MARGINAL 
WIND ADVISORY SPEEDS WORKING A LITTLE FARTHER EAST THAN ADVISORY 
AREA...THOUGH MODELS NOT SUPPORTIVE OF THESE WINDS LASTING PAST 
SUNSET SO GOING ADVISORY AREA AND EXPIRATION AT 6PM LOOKS GOOD. 
BREEZY CONDITIONS WILL LINGER INTO THE EVENING...WITH WINDS TAILING 
OFF TO 10-15 MPH AFTER MIDNIGHT...THOUGH SHOULD STAY UP ENOUGH WITH 
AREAS OF MAINLY MID CLOUDS AROUND TO KEEP TEMPS IN THE 20S BY 
MORNING.

WHILE NWRLY LO LVL/SFC FLOW OF COLD AIR WILL CONT FOR THE NEXT 2-3 
DAYS AS COLD TROF MOVES ACRS AREA...WNDS SHUD NOT BE AS STG...THO 
STG ENUF TO KEEP MAKING A DIFRNCE WITH WIND CHILLS. OTRW VRBL CLD 
CVR SHUD SETTLE INTO A CLDY/MOCLDY PERIOD BY LATE WED OR WED EVE AS 
BACK END OF COLD UPPER TROF MOVES OVER. INCRS IN MID AND LO LVL 
MOISTURE MEANS WE WILL KEEP MENTN OF FLRYS IN FOR WED NGT INTO THU 
NGT. IF THERE IS ENUF LIFT WITH PASSING TROF A FEW AREAS OF BARELY 
MEASRBL SNOW PSBL BUT HAVE OPTED TO KEEP IT AS FLRYS FOR NOW. TEMPS 
WILL OF COURSE BE COLDER WITH COLDER MET LOOKING BETTER THAN MAV ON 
HIGHS DESPITE LACK OF SNOW CVR.

FOLLOWING PASSAGE OF COLD TROF...ANOTHER LOBE WILL ROTATE BACK INTO 
WRN GRTLKS AS STG WAVE COMING ACR PAC RDG DIGS INTO WRN USA. NRN 
PLAINS SHUD BE IN A BENIGN PATTRN FOR THE WEEKEND WITH VRBL CLD CVR 
BUT NO PCPN...AND TEMPS SHOWING PERHAPS SOME VERY SLGT WARMING BUT 
STAYING A LTL BLO NORMAL.

ERY AND MID PART OF NEXT WEEK IS DEPENDENT ON HOW MUCH OF WRN USA 
SYS COMES ACRS INTO PLAINS AND OF COURSE HOW FAST. GFS SHOWS WEAK 
WAVES COMING OUT AS MAIN SYS EVENTUALLY IS DAMPENED BY 
RESTRENGTHENING NWRLY FLOW ACRS WRN CAN. ECMFW AND NOGAPS SHOW A 
POTENTIALLY MORE IMPORTANT SYS COMING UP BY TUE/TUE NGT THO NOT A 
MONSTER. AS THIS FCST GOES ONLY THRU TUE...WILL TEMPER WITH A SLGT 
CHC SNOW FOR MON NGT AND TUE AND LOOK TO RE EVALUATE THIS IN WED 
FCST. OTRW...THE FCST WEEK SHUD BE COLD BUT MOSTLY DRY.  

&& 

.AVIATION...
PRIMARILY VFR EXPCD THRU 09Z TNGT...WITH PATCHY MVFR CIGS WORKING 
SOUTHWARD INTO HIGHWAY 14 CORRIDOR EAST OF KHON AFTER 09Z...AND 
PUSHING INTO I-90 CORRIDOR NEAR/EAST OF KFSD AFTER 14Z WEDENSDAY. 

STG NWLY WINDS...SUSTAINED AT 25-30KTS WITH BRIEF GUSTS TO 40 KTS... 
SHOULD DECOUPLE AFTER 23Z AS SUN SETS...THOUGH GUSTS AOA 25KTS WILL 
PERSIST THROUGH THE EVENING...ESPECIALLY EAST OF THE JAMES VALLEY. 
WIND GUSTS OF 20-25KTS WILL AGAIN BE POSSIBLE WEDNESDAY AFTERNOON... 
ESPECIALLY IN SOUTHERN PARTS OF THE FORECAST AREA NEAR THE MISSOURI 
RIVER.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
MN...NONE.
NE...NONE.
SD...WIND ADVISORY THROUGH 6 PM CST THIS EVENING FOR 
     SDZ038-039-050-052>054-057>060-063-064.

$$
JH/WILLIAMS