508 
FXUS63 KFSD 231838
AFDFSD

AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NATIONAL WEATHER SERVICE SIOUX FALLS SD
138 PM CDT SUN SEP 23 2012


.DISCUSSION.../ISSUED AT 1218 PM CDT/
PLEASANT EARLY FALL DAY UNDER WAY ACROSS THE AREA TODAY. COPIOUS 
SUNSHINE AND LIGHT WINDS ARE ALLOWING TEMPERATURES TO WARM INTO THE 
50S ON THE WAY TO HIGHS IN THE 60S TO LOW 70S. FORECAST IS IN GOOD 
SHAPE AND NO UPDATES ARE ANTICIPATED.


&&

.AVIATION.../FOR THE 18Z TAF ISSUANCE/
VFR CONDITIONS WILL CONTINUE THROUGH 24/18Z.   

&&

.PREV DISCUSSION.../ISSUED AT 330 AM CDT/
A PLEASANT FALL DAY IS IN STORE ACROSS THE AREA TODAY. WITH THE 
TROUGH SHIFTING EAST AND LIGHT SOUTHERLY RETURN FLOW 
DEVELOPING...EXPECT TEMPERATURES TO BE SEVERAL DEGREES WARMER THAN 
YESTERDAY. GENERALLY THINKING LOW 60S SOUTHWEST MINNESOTA TO AROUND 
70 ALONG THE MISSOURI RIVER. SKIES SHOULD BE MOSTLY SUNNY WITH JUST 
SOME SCATTERED CIRRUS...AND WINDS SHOULD BE LIGHT...PICKING UP A BIT 
WEST OF THE JAMES RIVER BY AFTERNOON. TONIGHT WILL BE COOL...BUT NOT 
NEARLY AS COLD AS THIS MORNING...AS LOW LEVEL TEMPERATURE PROFILE IS 
WARMER AND EXPECT A LIGHT SOUTHERLY WIND TO STAY UP. STILL SHOULD 
SEE UPPER 30S TO LOW 40S MOST SPOTS.

MONDAY WILL SEE HIGH TEMPERATURES UP AROUND 15 DEGREES WARMER THAN 
MONDAY AS MODEL MEAN 850MB TEMPERATURES JUMP TO AROUND 14-18C. 
MOSTLY SUNNY SKIES AND GOOD MIXING WILL THUS ALLOW HIGHS TO CLIMB 
INTO THE UPPER 70S TO LOWER 80S...WITH EVEN SOME MID 80S WEST OF THE 
JAMES RIVER. WINDS WILL BE MORE BLUSTERY OUT OF THE 
WEST...ESPECIALLY EAST OF INTERSTATE 29...WHERE GUSTS TO 25 MPH ARE 
LIKELY. WITH AFTERNOON RELATIVE HUMIDITY FALLING TO BELOW 25 
PERCENT...FIRE DANGER WILL BE HIGH TO VERY HIGH...ALTHOUGH SHOULD 
STAY BELOW RED FLAG CRITERIA. BACKDOOR COOL FRONT PUSHES THROUGH 
MONDAY NIGHT INTO TUESDAY. MODELS IN PRETTY GOOD AGREEMENT ON TIMING 
OF THIS FRONT...WHICH ONLY IMPACT WILL BE COOLER TEMPERATURES AND A 
WIND SHIFT TO THE NORTHEAST. COOLER AIR SLOW TO WORK IN ON 
TUESDAY...SO WHILE IT WILL BE COOLER THAN MONDAY...HIGHS FROM AROUND 
70 IN SOUTHWEST MINNESOTA TO NEAR 80 ALONG THE MISSOURI RIVER SEEM 
PROBABLE. LOWS BOTH MONDAY AND TUESDAY NIGHT MAINLY IN THE 
40S...WITH SOME UPPER 30S POSSIBLE TUESDAY NIGHT BEHIND THE BACKDOOR 
FRONT.

THE EXTENDED PERIOD...WEDNESDAY THROUGH SATURDAY...WILL SEE A COUPLE 
WEAK UPPER LEVEL LOWS PUSH EAST ACROSS THE PLAINS...HOWEVER OVERALL 
PRECIPITATION CHANCES FOR OUR AREA LOOK LOW. THE BACKDOOR COOL 
FRONT AND GREAT LAKES HIGH WILL HELP KEEP THE FIRST WAVE AND ITS 
MOISTURE TO OUR SOUTH THROUGH THURSDAY. TEMPERATURES WEDNESDAY AND 
THURSDAY SHOULD BE A FEW DEGREES ABOVE NORMAL. RAISED HIGHS SOME 
OVER CONSENSUS VALUES...WHICH APPEAR TO BE SEVERAL DEGREES TOO COOL 
FOR EXPECTED 850MB TEMPERATURES. WEDNESDAY SHOULD SEE UPPER 60S TO 
MID 70S...WITH THURSDAY A COUPLE DEGREES WARMER AS GREAT LAKES 
TROUGH PUSHES EAST. BY FRIDAY...GFS AND ECMWF IN GOOD AGREEMENT 
THAT ANOTHER WAVE WILL MEANDER SOUTHEAST FROM CANADA INTO OUR 
VICINITY. NOT A TON OF MOISTURE WITH THIS WAVE...BUT ENOUGH THAT 
COMBINED WITH SOME WEAK INSTABILITY WE COULD SEE SOME LIGHT SHOWER 
AND THUNDERSTORM ACTIVITY AS THE TROUGH AXIS PUSHES ACROSS. THUS DID 
INTRODUCE SOME SLIGHT POPS FRIDAY NIGHT INTO SATURDAY NIGHT FOR 
PORTIONS OF THE AREA. TEMPERATURES FRIDAY INTO SATURDAY LOOK TO STAY 
A LITTLE ABOVE NORMAL...MAINLY 70S. LOWS IN THE EXTENDED SHOULD SEE 
A WARMING TREND...WITH MAINLY 40S WEDNESDAY NIGHT AND MORE 50S BY 
SATURDAY NIGHT. /CHENARD

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
MN...NONE.
NE...NONE.
SD...NONE.


&&

$$