Area Forecast Discussion
Issued by NWS Sioux Falls, SD

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42
000
FXUS63 KFSD 241639
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1139 AM CDT FRI OCT 24 2014

.UPDATE...
ISSUED AT 1138 AM CDT FRI OCT 24 2014

FOG HAS DISSIPATED AT MID MORNING AS EXPECTED...AND NOW WILL BE
DEALING WITH A QUIET AND MILD DAY. PROBLEM IS THE EXTENT OF CIRRUS
ACROSS THE AREA. DO EXPECT THIS TO THIN GOING THROUGH THE
AFTERNOON...BUT GIVEN THE WEAK FLOW BELOW IMPRESSIVE INVERSION ON
THE KABR 12Z RAOB...WILL PERHAPS BE A STRUGGLE TO WARM QUITE AS
MUCH AS EXPECTED. LOOKS LIKE TEMPS WILL START TO COME UP FAIRLY
QUICKLY INTO THE UPPER 60S TO LOWER 70S...AT WHICH TIME A BIT
STRONGER WEST TO NORTHWEST WIND WILL DEVELOP...AND WARMING RATES
WILL SLOW CONSIDERABLY. COULD STILL SEE A FEW READINGS TOWARD THE
UPPER 70S IN LOWER BRULE LOCATIONS...BUT MOSTLY LOWER TO A FEW MID
70S EXPECTED.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 255 AM CDT FRI OCT 24 2014

UPPER RIDGE WILL REMAIN IN PLACE THROUGH FRIDAY NIGHT...CENTERED
ACROSS THE SOUTHWESTERN PLAINS...EXTENDING NORTHWARD THROUGH THE
REST OF THE WESTERN PLAINS. THIS WILL HELP TO GIVE EXTREMELY MILD
TEMPERATURES FOR THIS TIME OF YEAR TODAY...BUT LOOKS TO BE SHORT OF
RECORDS AS THEY ARE STILL IN THE 80S.

BUT FIRST...PARTS OF THE FORECAST AREA MAY HAVE TO CONTEND WITH
MORNING FOG AGAIN. THE ORGANIZED AREA OF DENSE FOG IS TO THE EAST OF
OUR FORECAST AREA...WITH SOME INDICATIONS PER THE HRRR AND RAP13
THAT THIS FOG MAY BACK INTO OUR EXTREME EASTERN ZONES AROUND SUNRISE
WHEN THE SOUTHERLY FLOW DECREASES. THEREFORE KEPT AREAS OF FOG GOING
IN THAT AREA AROUND SPENCER AND STORM LAKE IA. ELSEWHERE DEW POINT
TEMPERATURES AT THE SURFACE ARE CREEPING UP...ADVECTING NORTHWARD
FROM NEB. IN ADDITION...A WEAK SURFACE TROUGH IS MOVING SLOWLY
EASTWARD...CURRENTLY BETWEEN CHAMBERLAIN AND THE JAMES RIVER VALLEY.
AS IT MOVES EASTWARD...THE SOUTHERLY FLOW WILL CONTINUE TO DECREASE
IN THE PRE DAWN HOURS ALONG THE I 29 CORRIDOR AND EAST CENTRAL SD.
SURFACE DEW POINT DEPRESSIONS ARE ALREADY GETTING SMALL IN EAST
CENTRAL SD...WHERE AGAIN THE HRRR AND RAP13 DEVELOP FOG BY
SUNRISE...THEN DRAIN SOME OF IT SOUTHEASTWARD TOWARD PIPESTONE AND
LUVERNE MN ALONG THE WEST SIDE OF THE BUFFALO RIDGE. ACCOUNTED FOR
THIS POSSIBILITY IN THE FORECAST BY ADDING AN AREAS OF FOG MENTION
FOR OUR EAST CENTRAL SD ZONES. OTHERWISE ANY FOG DEVELOPMENT SHOULD
ABATE BY AROUND 15Z OR SLIGHTLY LATER...LEAVING SOME CIRRUS IN PLACE
FOR THE REST OF THE DAY. BUT HIGHS LOOK VERY MILD...WITH THE RAW
BIAS CORRECTED VALUES LOOKING THE BEST IN GIVING READINGS WELL INTO
THE 70S. WINDS AS THEY SHIFT TO THE WEST OR NORTHWEST WILL ALSO NOT
BECOME VERY STRONG AT ALL...SO LOOKS LIKE A VERY PLEASANT AFTERNOON.

NOT A LOT GOING ON TONIGHT WITH HIGH PRESSURE IN CONTROL. GENERALLY
LOOKING AT LOWS ABOUT 40 TO 45 UNDER LIGHT WINDS AND MOSTLY CLEAR
SKIES.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 255 AM CDT FRI OCT 24 2014

STILL LOOKS LIKE A PLEASANT WEEKEND ACROSS THE REGION WITH UPPER
RIDGING BUILDING IN. TEMPERATURES ALOFT COOL A BIT BEHIND TODAYS
FRONT...BUT SHOULD STILL SEE 60S AND 70S BOTH DAYS. BASED ON LATEST
GUIDANCE...DID BUMP HIGHS UP A TAD BOTH DAYS. SOME UNCERTAINTY ON
SUNDAY...AS LOW LEVEL MOISTURE INCREASES. COULD BE ENOUGH TO GET
SOME LOW STRATUS TO DEVELOP...WHICH IF IT DOES...COULD HOLD
TEMPERATURES DOWN. SO WILL STAY CONSERVATIVE ON HIGHS SUNDAY...BUT
IF IT STAYS SUNNY WILL LIKELY END UP WARMER THAN CURRENT FORECAST.
SHOULD STAY DRY THROUGH SUNDAY...AS DESPITE SOME FORCING...MID
LEVELS REMAIN QUITE DRY. LOOKING AT LOWS IN THE 40S SATURDAY NIGHT
AND CLOSER TO 50 SUNDAY NIGHT AS WE STAY MORE MIXED.

MODELS COMING INTO BETTER AGREEMENT ON EVOLUTION OF THE TROUGH
MOVING ACROSS THE PLAINS EARLY NEXT WEEK. BEST FORCING COMES POST
FRONTAL...AND LOOKS LIKE THE TROUGH WILL STAY POSITIVELY TITLED AS IT
SWINGS ACROSS. THUS FORCING AND MOISTURE NOT ALL THAT GREAT. STILL
LOOKS LIKE WE COULD SEE A FEW SHOWERS MONDAY INTO MONDAY NIGHT...BUT
NOT EXPECTING ANYTHING SIGNIFICANT. WITH MOSTLY CLOUDY SKIES AND
COLDER TEMPERATURES MOVING IN ALOFT...MONDAY WILL SEE HIGHS IN THE
50S AND 60S...WARMEST IN NORTHWEST IOWA.

COLDER AIR MOVES IN BEHIND THE TROUGH...WITH TUESDAY LIKELY THE
COOLEST DAY. WILL BE MUCH COOLER THAN WHAT WE HAVE BEEN
SEEING...WITH LOW TO MID 50S EXPECTED. ALTHOUGH THESE VALUES ARE
ONLY SLIGHTLY BELOW AVERAGE. SHOULD BE BREEZY ON TUESDAY AS
WELL...WITH NORTHWESTERLY WINDS GUSTING AROUND 30 MPH. MODELS
DIVERGE MID WEEK...DUE TO DIFFERENCES ON STRENGTH OF OUR NEXT
NORTHERN STREAM WAVE. SO FOR NOW WILL STAY WITH CONSENSUS VALUES
FOR HIGHS...GIVING MID 50S. AT THIS TIME DOES NOT LOOK LIKE WE SEE
ANY GREAT RADIATIONAL COOLING NIGHTS...WITH HIGH PRESSURE NEVER
SETTLING OVERHEAD. THUS DESPITE THE COOLER TEMPERATURES ALOFT...AS
OF NOW JUST GOING WITH LOWS IN THE 30S TUESDAY NIGHT THROUGH
THURSDAY NIGHT. NOT SEEING ANY GREAT PRECIPITATION CHANCES THROUGH
THE END OF NEXT WEEK AS OF NOW.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1138 AM CDT FRI OCT 24 2014

VFR CONDITIONS ARE EXPECTED THROUGH 18Z SAT.

&&

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

$$

UPDATE...CHAPMAN
SHORT TERM...MJ
LONG TERM...CHENARD
AVIATION...CHAPMAN



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.