Area Forecast Discussion
Issued by NWS Sioux Falls, SD

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FXUS63 KFSD 290441
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1040 PM CST WED JAN 28 2015

.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 254 PM CST WED JAN 28 2015

ACTIVE FORECAST TONIGHT WITH COLD FRONT FRONT MOVING THROUGH THE
AREA WITH STRATUS AND WINDS TO FOLLOW.  WINDS WILL INCREASE A FEW
HOURS BEHIND THE SURFACE FRONT.  STRONGEST PRESSURE RISES WILL BE
ACROSS CENTRAL SOUTH DAKOTA FUNNELING DOWN THE MISSOURI RIVER
VALLEY...WHILE THE STRONGEST WINDS ALOFT WILL BE ACROSS THE EAST.
THE NET RESULT WILL BE A LOW END ADVISORY ACROSS THE AREA THROUGH
THE OVERNIGHT HOURS.

THE OTHER ISSUE WILL BE THE STRATUS AND POTENTIAL PRECIPITATION
FROM IT.  MODEL SOUNDINGS SHOW A FAIR AMOUNT OF SATURATION IN THE
LOW LEVELS OF THE ATMOSPHERE...WITH A LACK OF SATURATION ALOFT.
GIVEN THE LACK OF ICE PRODUCTION...ONLY CHANCE FOR PRECIPITATION
WILL BE DRIZZLE OR FREEZING DRIZZLE.  MODELS ARE STILL PRODUCING
SOME LIGHT PRECIPITATION ACROSS SOUTHWEST MINNESOTA...SO LEFT SOME
LOW END CHANCE POPS THERE.  HOWEVER...WITH WEAK LIFT AT THE TOP OF
THE SATURATED LAYER AND ABOVE...COULD NOT RULE OUT DRIZZLE ACROSS
THE FORECAST AREA...AND TURBULENCE WITHIN THE CLOUD LAYER SHOULD AID
IN THE COLLISION/COALESCENCE PROCESS.

WITH LOW TEMPERATURES GENERALLY A FEW DEGREES BELOW FREEZING AND
SURFACE TEMPERATURES AT OR JUST BELOW FREEZING...ANY PRECIPITATION
COULD BE QUITE PROBLEMATIC.

FOR TOMORROW...STILL SHOULD BE A BREEZY DAY ACROSS THE AREA WITH 925
HAP WINDS TRENDING DOWN FROM 40-45 KNOTS EARLY IN THE DAY TOWARDS 20
KNOTS BY LATE AFTERNOON.  HAVE REALLY INCREASED CLOUD COVER ACROSS
THE AREA AS MODEL SOUNDINGS SHOW STEEP LAPSE RATES IN THE LOW
LEVELS.  THE NAM IS WEAKLY UNSTABLE SUGGESTING ANY OF THE BREAKS IN
THE CLOUD COVER WOULD BE QUICKLY FILLED IN DUE TO SELF DESTRUCTIVE
SUNSHINE...HOWEVER...THE NAM HAS BEEN TOO MOIST IN THE BOUNDARY
LAYER AS OF LATE.  EVEN THE GFS WOULD SUGGEST A FAIRLY HEALTHY CLOUD
DECK HANGING THROUGH THE MORNING HOURS...AND POTENTIALLY DEVELOPING
A FEW BREAKS IN THE AFTERNOON AS THE MOISTURE WITHIN THE CLOUD DECK
CONTINUES TO THIN.  HAVE KEPT FORECAST HIGHS VERY SIMILAR TO
PREVIOUS FORECAST...GENERALLY IN THE UPPER 20S AND 30S.

.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 254 PM CST WED JAN 28 2015

THE PRIMARY CONCERNS IN THE MEDIUM AND EXTENDED FORECAST REMAINS
FOCUSED PRECIPITATION POTENTIAL THIS WEEKEND ALONG WITH TEMPERATURES
INTO NEXT WEEK.  AFTER FLOPPING BACK AND FORTH IN THE PAST 24 HOURS
REGARDING PRECIPITATION CHANCES SATURDAY NIGHT AND SUNDAY...LATEST
GUIDANCE SEEMS TO HAVE AGAIN SHIFTED BACK TOWARDS A DRIER SOLN FOR
THE MIDDLE OF THE WEEKEND...PUTTING MORE EMPHASIS ON STRONGER
RIDGING OVER THE EASTERN PACIFIC.  THIS SOLN SUPPORTED BY THE
GFS/GEFS/ECMWF WOULD SUGGEST THAT A STRONGER NORTHERN STREAM
WOULD DOMINATE THE FLOW...KEEPING BROAD TROUGHING OVER THE
SOUTHWESTERN CONUS CONFINED TO THE SOUTHERN PLAINS. THIS SOLN
WOULD BRING THE SLIGHTLY STRONGER CLIPPER THROUGH THE NORTHERN
PLAINS LATE SATURDAY INTO SATURDAY NIGHT. WITH THIS SYSTEM STARVED
FOR MOISTURE...WOULD ANTICIPATE LOW PRECIPITATION AMOUNTS WITH
GENERALLY UPWARDS OF AN INCH OF SNOW POSSIBLE. AGAIN...GIVEN
MODEL VARIABILITY WITH THIS WEEKEND...THE FORECAST MAY REMAIN MORE
FLUID THAN TYPICAL.

OUR STREAK OF CONSECUTIVE ABOVE NORMAL JANUARY DAYS WILL LIKELY
REACH 18 BY THIS WEEKEND...BUT WILL COME TO A HALT ON SUNDAY AS A
STRONG COLD FRONT MOVES THROUGH THE REGION.  HIGHS SUNDAY INTO
MONDAY WILL ACTUALLY FALL BELOW NORMAL.

THE DOMINATE FLOW PATTERN INTO NEXT WEEK WILL BE ONE THAT FEATURES
NEAR TO SLIGHTLY BELOW TEMPERATURES...AND AGAIN THE APPEARANCE OF
NO MAJOR SYSTEMS...BUT SEVERAL MINOR WAVES. A QUICK MOVING WAVE
WILL ZIP THROUGH THE REGION ON MONDAY...AND POPS MAY NEED TO BE
INCREASED IN FUTURE FORECASTS. AS TYPICAL IN THIS PROGRESSIVE NW
FLOW REGIME...THE TRACK OF THESE WAVES IS USUALLY IN DOUBT. INTO
THE MIDDLE OF THE WEEK...CONTINUED THE TRENDS OF NEAR NORMAL
TEMPERATURES AND DRY CONDITIONS.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1040 PM CST WED JAN 28 2015

MVFR TO IFR CONDITIONS AND STRONG NORTHWEST WINDS GUSTING AS HIGH AS
30-40KT WILL BE THE PRIMARY AVIATION CONCERNS INTO THURSDAY MORNING.
AREAS OF MAINLY DRIZZLE WILL MOVE THROUGH THE AREA PRIOR TO 12Z...
MOST FAVORED EAST OF INTERSTATE 29 WHERE IFR VISIBILITY IS ALSO MORE
LIKELY.

STRONGEST WINDS WILL GRADUALLY SUBSIDE WEST TO EAST AFTER 12Z...
THOUGH GUSTS OF 20-30KT LIKELY WELL INTO THE AFTERNOON. ANTICIPATE
IMPROVEMENT TO VFR CONDITIONS THROUGH THE AFTERNOON AS STRATUS LAYER
GRADUALLY THINS AND BECOMES SCATTERED...THOUGH MVFR CEILINGS COULD
LINGER NORTH AND EAST OF KFSD INTO THE EARLY EVENING.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY UNTIL 9 AM CST THURSDAY FOR SDZ040-056-062-066-067-
     070-071.

     WIND ADVISORY UNTIL 6 AM CST THURSDAY FOR SDZ038-039-050-052>055-
     057>061-063>065-068-069.

MN...WIND ADVISORY UNTIL 9 AM CST THURSDAY FOR MNZ071-072-080-081-089-
     090-097-098.

IA...WIND ADVISORY UNTIL 9 AM CST THURSDAY FOR IAZ001>003-012>014-
     020>022-031-032.

NE...WIND ADVISORY UNTIL 9 AM CST THURSDAY FOR NEZ013-014.

&&

$$

SHORT TERM...
LONG TERM...DUX
AVIATION...JH


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