226 
FXUS63 KFSD 011741
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1241 PM CDT THU OCT 1 2015

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 344 AM CDT THU OCT 1 2015

SAME PATTERN...DIFFERENT DAY...AS A STRONG SURFACE RIDGE REMAINS 
ORIENTED FROM EASTERN CANADA INTO THE UPPER MISSISSIPPI VALLEY. 
SEEING A FAIRLY SOLID AREA OF HIGH STRATUS FROM THE INTERSTATE 29 
CORRIDOR AND WESTWARD VERY EARLY THIS MORNING. ALTHOUGH MODELS ARE 
DOING FAIRLY POORLY ON THE PLACEMENT OF THIS CLOUD COVER...THEY ARE 
REFLECTING AN OVERALL THEME OF SLOWLY DRYING MIDLEVELS THROUGH THE 
DAY...SO EXPECT THESE CLOUDS TO BREAK UP SOME BY AFTERNOON. IT WILL 
AGAIN BE BREEZY IN OUR WEST THIS AFTERNOON WITH A DECENT GRADIENT 
OVER THAT AREA. SLIGHTLY COOLER AIR WILL CONTINUE TO BACK INTO THE 
REGION FROM THE EAST TODAY...SO LOOKING AT HIGHS A COUPLE OF DEGREES 
COOLER THAN YESTERDAY...IN THE MID 60S TO NEAR 70.

TONIGHT WILL BE ANOTHER COOL NIGHT WITH MAINLY HIGH CLOUDS 
INCREASING IN THE WEST OVERNIGHT. LOWS WILL RANGE FROM THE UPPER 30S 
TO LOWER 40S THROUGH THE EASTERN HALF OF OUR CWA...TO UPPER 40S OVER 
OUR SOUTH CENTRAL SOUTH DAKOTA ZONES.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 344 AM CDT THU OCT 1 2015

FAIRLY QUIET AUTUMN WEATHER EXPECTED THROUGH THE MIDDLE-LONGER RANGE 
OF THE FORECAST...AS BLOCKING PATTERN LARGELY KEEPS PRECIP CHANCES 
WEST OF OUR FORECAST AREA INTO EARLY NEXT WEEK. DRY EASTERLY LOW 
LEVEL FLOW SHOULD HELP KEEP RAIN AT BAY FOR LOCATIONS NEAR/EAST OF 
THE JAMES VALLEY...BUT MORE ABUNDANT MID LEVEL CLOUDS IN OUR FAR 
WEST COULD SQUEEZE OUT SOME LIGHT SHOWERS AT TIMES. BEST CHANCE 
CURRENTLY LOOKS TO BE LATER FRIDAY NIGHT INTO SATURDAY...AS WESTERN 
TROUGH EDGES EASTWARD AND MID-UPPER LEVEL WAVE SWINGS UP THROUGH THE 
PLAINS. WEEKEND TEMPERATURES ON THE COOL SIDE...WITH HIGHS A DEGREE 
OR TWO EITHER SIDE OF 60. LOWS SHOULD BE CLOSER TO EARLY OCTOBER 
NORMALS IN THE LOWER TO MID 40S FOR MOST...COOLEST IN THE EAST WHERE 
CLEAR SKIES ARE FAVORED AND NIGHTTIME WINDS MAY DROP OFF A BIT MORE 
WITH PROXIMITY TO SURFACE RIDGE.

DOMINANT EASTERN CANADIAN HIGH...FROM WHICH OUR PERSISTENT SURFACE 
RIDGE EXTENDS...FINALLY BREAKS DOWN LATE SUNDAY NIGHT INTO MONDAY. 
AS RIDGE AXIS WEAKENS AND SHIFTS EASTWARD...LOW LEVEL FLOW WILL TURN 
MORE SOUTHERLY...ALLOWING WARMER AIR AND SLIGHTLY HIGHER MOISTURE TO 
SPREAD INTO THE REGION LATE MONDAY-TUESDAY. FAIR MODEL AGREEMENT ON 
A FRONTAL BOUNDARY MOVING THROUGH THE REGION TUESDAY/TUESDAY NIGHT 
WHICH SHOULD BRING A CHANCE OF SHOWERS OR A FEW THUNDERSTORMS TO 
MORE OF THE FORECAST AREA DURING THIS PERIOD. DAYTIME HIGHS MUCH OF 
NEXT WEEK LOOK PRETTY CLOSE TO SEASONAL NORMALS IN THE 60S...WITH 
TUESDAY LIKELY THE WARMEST DAY THANKS TO THERMAL RIDGE/MIXING AHEAD 
OF THE BOUNDARY.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1240 PM CDT THU OCT 1 2015

VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD.

&&

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

$$

SHORT TERM...JM
LONG TERM...JH
AVIATION...