854 
FXUS63 KFSD 282339
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
639 PM CDT MON SEP 28 2015

.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 300 PM CDT MON SEP 28 2015

BAND OF SHOWERS DROPPING GRADUALLY SOUTH AS DRIER AIR FILTERS IN 
FROM THE NORTH. THE TIMING AND LOCATION OF THE PRECIPITATION TONIGHT 
WILL BE A BATTLE BETWEEN HOW FAR SOUTH THE MID LEVEL BOUNDARY DROPS 
VERSUS HOW LONG IT WILL TAKE FOR THE UPPER LEVEL WAVE TO WORK ONTO 
THE PLAINS. THIS WAVE WAS MOVING THROUGH EASTERN WYOMING EARLY THIS 
AFTERNOON AND APPEARS TO BE ON A DIRECT PATH FOR THE SOUTHERN CWA. 
THIS WOULD HINT AT THE NEED FOR SOME HIGHER POPS ALONG THE MISSOURI 
RIVER INTO PARTS OF NORTHWEST IOWA FROM ABOUT 0Z THROUGH 8Z OR SO. 
AFTER THIS MOST OF THE PRECIPITATION WILL BE SOUTH OF THE AREA AND 
SKIES WILL LIKELY CLEAR FROM THE NORTH. WITH A HIGHER CHANCE OF 
CLEARING SKIES IN THE NORTHERN CWA WENT AHEAD AND LOWERED LOWS A FEW 
DEGREES...CLOSER TO 40 DEGREES. THE FAR SOUTHERN CWA WILL LIKELY 
REMAIN IN CLOUD COVER ALL NIGHT SO NOT AS MUCH OF A FALL...CLOSER TO 
50 TO 55.
 
DRY...COOL HIGH PRESSURE SETTLES INTO THE AREA ON TUESDAY BRINGING 
CLEAR SKIES FOR ALL BUT CENTRAL SD. WITH WINDS ON THE LIGHTER SIDE 
OTHER THAN A COOL START TO THE MORNING IT SHOULD PROVE TO BE A VERY 
PLEASANT DAY WITH HIGHS IN THE MID TO UPPER 60S.

.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 300 PM CDT MON SEP 28 2015

THE MAIN FEATURE OF THE WHOLE TUESDAY NIGHT THROUGH MONDAY PERIOD IS 
A DRY INFLOW BELOW MID LEVELS...QUITE DRY AT TIMES...FROM THE 
NORTHEAST AND EAST WITH PERSISTENT HIGH PRESSURE IN THAT DIRECTION. 
THIS IS HAPPENING AS AN UPPER TROUGH DIGS OVER THE EASTERN/ 
SOUTHEASTERN USA...AND AN UPPER RIDGE BUILDS OVER CENTRAL AND 
SOUTHEASTERN CANADA. THIS SHOULD COUNTER THE THERMAL RIBBON RELATED 
SHOWERS TUESDAY NIGHT AND WEDNESDAY...AND THE MOISTURE INCREASE AND 
SHOWERS THAT APPROACH THE AREA FROM THE SOUTHWEST LATER IN THE WEEK 
WITH AN APPROACHING WESTERN USA TROUGH. 

THE END RESULT IS AN OCCASIONAL TAME SHOWER THREAT OVER THE 
SOUTHWEST PART OF THE FORECAST AREA AND A DRY REGIME TO THE 
NORTHEAST. THE EXTENDED GUIDANCE HAS THIS THEME AND LOOKS GOOD...SO 
WE WILL HAVE OCCASIONAL LIGHT SHOWER CHANCES WEST TO SOUTH OF FSD 
AND DRY FROM FSD NORTH AND EAST.

BY THE WEEKEND...THE APPROACHING WESTERN TROUGH SEEMS SET TO SWING 
UP INTO THE AREA AND WEAKEN OR EVEN DISSIPATE...SO DRY LOOKS GOOD 
FOR THE WHOLE AREA SUNDAY INTO MONDAY. AFTER THEN...ANOTHER 
APPROACHING TROUGH COULD BRING A RAIN THREAT EARLY NEXT WEEK AFTER 
THE FORECAST PERIOD...THOUGH OF COURSE DETAILS ON THAT ARE GREATLY 
SUBJECT TO CHANGE.

TEMPERATURES LOOK TO BE ON THE MODESTLY COOL SIDE THROUGH THIS 
[PERIOD WITH NOT A LOT OF DAY TO DAY CHANGE. SINCE WE ARE GETTING 
INTO OCTOBER...THE WORD MODESTLY WITH THE COOL MEANS THAT FOR NOW WE 
SEE NO REAL FIRST FREEZE THREAT. LOWS WILL BE MOSTLY IN THE 40S AND 
HIGHS IN THE UPPER 50S AND 60S.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 635 PM CDT MON SEP 28 2015

MID CLOUDS WILL BE ABUNDANT TONIGHT...HOWEVER DRY LOW LEVELS WILL
CREATE VFR CONDITIONS LASTING THROUGH TUESDAY.

&&

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

$$

SHORT TERM...08
LONG TERM...
AVIATION...MJ