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 43 44 45 46 47 48 49 50
000
FXUS63 KFSD 061802
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
102 PM CDT SUN JUL 6 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 344 AM CDT SUN JUL 6 2014

LOW CLOUDS OVER PART OF NORTHWEST IA AND SOUTHWEST MN ARE ALREADY
BEING HELD AT BAY FROM ADVANCING FURTHER WEST BY LOW LEVEL WINDS
SLOWLY SWINGING AROUND TO SOUTHWESTERLY. THESE SHOULD CONTINUE TO
GET PUSHED OUT BY DRIER AIR AND SHOULD NOT BE A FACTOR MUCH AFTER
DAYBREAK. FOG WITH THE LOW CLOUDS WILL ALSO BE STEADILY DRIED OUT.
EARLIER CHECK OF WHAT APPEARED TO BE DENSE FOG IN THE STORM LAKE
AREA FROM OBSERVATIONS AND A WEBCAM SHOWED THAT THE FOG IS NOT VERY
DENSE AND HAVE HELD OFF ON ADVISORY...ESPECIALLY WITH RAPID
IMPROVEMENT EXPECTED.

HIGH AND A FEW MIDDLE CLOUDS PASSING OVER THE AREA ARE EXPECTED TO
DECREASE. THE COLD FRONTAL PASSAGE THIS MORNING WILL START TO BRING
DRYING TODAY...THOUGH MIXING AND HEATING SHOULD STILL WARM
TEMPERATURES INTO THE UPPER 80S TO MID 90S. IN ANY EVENT...WITH THE
EARLY START TO THE DRYING AND NOT ENOUGH INSTABILITY OR WIND SUPPORT
FOR EARLY MORNING CONVECTIVE DEVELOPMENT...THE FORECAST FOR THE DAY
WILL BE DRY...EVEN FAR EAST WHERE WE HAD A LITTLE BIT OF A SLIGHT
CHANCE IN THE PREVIOUS FORECAST.

WINDS SHOULD DROP OFF STEADILY THIS EVENING AND BECOME LIGHT
TONIGHT. THE AIR WILL REMAIN FAIRLY DRY...AND DESPITE AN INCREASE IN
INSTABILITY COMING IN FROM THE SOUTHWEST LATE TONIGHT AHEAD OF A
NORTHWESTERLY SHORT WAVE APPROACHING...A DRY FORECAST WILL BE
CONTINUED WITH A LITTLE INCREASE IN CLOUDS FROM THE SOUTHWEST LATE.
TEMPERATURES OF COURSE WILL BE COOLER THAN THE CURRENT NIGHT WITH
LOWS IN THE LOW TO MID 60S.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 344 AM CDT SUN JUL 6 2014

SCATTERED THUNDERSTORM ACTIVITY IS EXPECTED TO FIRE UP ONCE AGAIN ON
MONDAY. MOISTURE WILL INCREASE INTO THE AFTERNOON HOURS AHEAD OF A
WEAK FRONTAL BOUNDARY DROPPING THROUGH THE NORTHERN PLAINS AND MOVING
ACROSS THE FORECAST AREA IN THE AFTERNOON AND EVENING. ELEVATED
INSTABILITY RAPIDLY INCREASES INTO THE AFTERNOON WITH A CAPPED
ENVIRONMENT AND INITIAL WEAK LIFT AND FORCING LIMITING ANY STORM
DEVELOPMENT EARLY IN THE DAY. CANNOT RULE OUT SOME ISOLATED TO LOW
END SCATTERED ACTIVITY LIFTING INTO OUR SOUTHWESTERN COUNTIES...BUT
CONVECTION SHOULD LARGELY HOLD OFF UNTIL LATER IN THE DAY WHEN THE
FRONT ARRIVES AND IS QUICKLY FOLLOWED BY THE MID LEVEL SHORTWAVE IN
THE EVENING. CAPE VALUES ARE FAIRLY HIGH AND DEEP LAYER SHEAR
INCREASES LATER IN THE DAY TO OVER 50 KT. SEVERE STORMS WILL BE
POSSIBLE LATE AFTERNOON INTO THE EARLY MORNING MAINLY ACROSS FAR
SOUTHEAST SOUTH DAKOTA AND INTO NORTHWEST IOWA AND NORTHEAST
NEBRASKA. MODELS SUGGEST INITIAL THREATS WITH SEVERE ACTIVITY WILL BE
LARGE HAIL AND DAMAGING WINDS...BUT CANNOT RULE OUT A SMALL TORNADO
THREAT NEAR ANY BOUNDARY. LATER IN THE EVENING AND EARLY
MORNING...STORMS WILL LIKELY MERGE INTO A MCS WITH MAINLY A WIND
THREAT AND QUICKLY EXIT THE FORECAST AREA TO THE EAST.

DRIER AND SLIGHTLY COOLER AIR ARRIVES BEHIND THE STORM SYSTEM ON
TUESDAY WITH SURFACE HIGH PRESSURE EXPANDING INTO THE PLAINS AND
UPPER LEVEL NORTHWEST FLOW. NORTHWEST WINDS WILL BE A LITTLE
BREEZY...OTHERWISE EXPECT MOSTLY SUNNY SKIES AND MILD TEMPERATURES
IN THE MID 70S TO LOWER 80S. UPPER LEVEL RIDGING FLATTENS AS IT
SHIFTS INTO THE HIGH PLAINS ON WEDNESDAY...HOWEVER WITH RETURN FLOW
DEVELOPING IN THE AFTERNOON HIGH TEMPERATURES WILL IMPROVE A FEW
DEGREES WITH SOME MID AND HIGH CLOUDS BUILDING INTO THE AREA FROM
THE WEST.

MODEL CONSISTENCIES DROP OFF LATER IN THE WEEK WITH WEST TO
NORTHWEST UPPER FLOW AND THE POSSIBILITY OF A FEW WEAK WAVES TO
TRACK THROUGH THE AREA. THE TIMING OF THESE WAVES REMAIN TOO
DIFFICULT TO PINPOINT WITH EACH MODEL SHOWING DIFFERENT TIMING...SO
DID NOT REALLY ALTER THE POPS MUCH WEDNESDAY NIGHT AND BEYOND.
TEMPERATURES ALSO HOVER WITHIN A FEW DEGREES OF NORMALS DURING THE
PERIOD.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 100 PM CDT SUN JUL 6 2014

VFR THROUGH THE PERIOD.

&&

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

$$

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






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