Severe Thunderstorm Warning 171, NWS Sioux Falls, SD

461 
WWUS53 KFSD 252238
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
538 PM CDT WED JUL 25 2012

IAC167-252248-
/O.EXP.KFSD.SV.W.0171.000000T0000Z-120725T2245Z/
SIOUX IA-
538 PM CDT WED JUL 25 2012

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL SIOUX COUNTY WILL
EXPIRE AT 545 PM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE WARNED
AREA...HOWEVER SMALL HAIL IS STILL POSSIBLE WITH THIS THUNDERSTORM.

LAT...LON 4295 9607 4312 9611 4322 9587 4321 9585
      4299 9586 4298 9586
TIME...MOT...LOC 2238Z 241DEG 12KT 4308 9590

$$

SCHUMACHER

AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NATIONAL WEATHER SERVICE SIOUX FALLS SD
337 PM CDT WED JUL 25 2012

.DISCUSSION...
PLENTY OF MID LEVEL CLOUDS CONTINUE TO MOVE INTO THE FORECAST AREA
ASSOCIATED WITH A MID LEVEL SHORT WAVE. SO FAR...MEASURABLE
PRECIPITATION HAS BEEN HARD TO REALIZE WITH VERY HIGH CLOUD BASES
AND WIDE DEW POINT DEPRESSIONS BELOW 700MB. THAT SAID...NO REASON TO
DROP OUR LOW POST FRONTAL POPS THAT WE HAVE GOING THROUGH EARLY
EVENING. DEEPER BEHIND THE FRONT...SURFACE DEW POINTS ARE CRASHING
INTO THE 50S AND LOWER 60S. COUPLED WITH LIGHT WINDS TONIGHT AND
THAT KIND OF DRIER AIR ADVECTING IN...LOWS IN THE 60S SHOULD FINALLY
COME TO PASS WHICH OF COURSE IS MUCH CLOSER TO SEASONAL NORMALS. ON
THURSDAY...DECIDED TO ELIMINATE OUR LOW POPS IN SOUTHWEST MN FOR THE
AFTERNOON HOURS. LATEST DETERMINISTIC MODELS SHOW THE CRUX OF THE
NEXT MID AND UPPER WAVE TO BE WELL EAST OF OUR EASTERN ZONES. AT
THIS TIME...THIS WAVE SHOWS UP AS A NICE CURL OF MID LEVEL MOISTURE
NEAR THE MANITOBA/SASKATCHEWAN BORDER IN SOUTH CENTRAL CANADA ON
WATER VAPOR. NAM 850MB TEMPERATURES CONTINUE TO COOL PROGRESSIVELY
FROM TODAY THROUGH THURSDAY. HIGH TEMPERATURES ON THURSDAY WILL
LIKELY BE SIMILAR TO TODAYS HIGHS THROUGHOUT OUR WESTERN ZONES...AND
A COUPLE OF CATEGORIES COOLER IN OUR EAST.

SHOULD SEE TEMPERATURES CLOSER TO NORMAL FOR A COUPLE OF DAYS TO END
THE WEEK...BEFORE UPPER RIDGE BUILDS BACK INTO THE PLAINS AND BEGINS
TO WARM THINGS UP AGAIN NEXT WEEK. SURFACE RIDGE ALONG WITH RISING
HEIGHTS ALOFT SHOULD HELP KEEP THURSDAY NIGHT/FRIDAY DRY WITH FAIRLY
LIGHT WINDS AND RELATIVELY COMFORTABLE DEW POINTS IN THE 50S. 850MB
WARM FRONT BEGINS TO LIFT THROUGH NEBRASKA AND SOUTH CENTRAL SOUTH
DAKOTA LATER FRIDAY NIGHT WITH MODELS SHOWING A WEAK WAVE TRACKING
INTO THE AREA AS WELL. COMBINATION COULD PRODUCE SCATTERED STORMS IN
THE MISSOURI VALLEY AFTER MIDNIGHT FRIDAY NIGHT...WITH THE CHANCE
SLIDING EAST THROUGH THE SOUTHERN HALF OF THE CWA SATURDAY...MAINLY
IN THE MORNING BEFORE THIS LEAD WAVE SHIFTS EAST INTO IOWA.

MODELS SHOWING A BROAD TRAILING WAVE MOVING ACROSS THE REGION FOR
THE LATTER HALF OF THE WEEKEND...ALONG WITH CONTINUED WEAK WARM
ADVECTION OVER THE EASTERN PART OF THE FORECAST AREA. WILL KEEP A
CHANCE OF PRECIPITATION AROUND...MAINLY ALONG/EAST OF I-29 THOUGH
TIMING/LOCATION OF BEST PRECIP CHANCE STILL A LITTLE UNCERTAIN WITH
MODELS SO HAVE LOWER-MID RANGE CHANCE POPS PRETTY BROAD-BRUSHED FOR
SATURDAY NIGHT AT THIS POINT.

SOMEWHAT MESSY PATTERN BEYOND THIS POINT THROUGH THE MIDDLE OF NEXT
WEEK...AS REGION REMAINS IN WEAK NORTHWEST FLOW BETWEEN UPPER RIDGE
ACROSS THE ROCKIES AND BROAD TROUGH OVER THE GREAT LAKES. DIFFICULT
TO PINPOINT ANY FAVORED PERIOD OR LOCATION FOR PRECIPITATION THROUGH
THE FIRST HALF OF THE WORK WEEK...SO HAVE LEFT MONDAY-WEDNESDAY DRY
FOR NOW...WITH TEMPERATURES WARMING BACK INTO THE UPPER 80S AND 90S.

&&

.AVIATION.../FOR THE 18Z TAF ISSUANCE/
PATCHY CUMULUS EARLY THIS AFTERNOON IN THE UPPER MVFR TO LOWER END
VFR RANGE WILL OCCUR ACROSS SECTIONS OF OUR FORECAST AREA...
OTHERWISE VFR CONDITIONS SHOULD BE THE DOMINANT CATEGORY THROUGH
THURSDAY MORNING. THERE IS A SMALL CHANCE FOR THUNDERSTORMS LATE
THIS AFTERNOON AND EARLY EVENING BEHIND A DEPARTING COLD FRONT IN
THE SIOUX CITY AND STORM LAKE IOWA AREAS. BUT COVERAGE WILL LIKELY
BE TOO SPOTTY TO MENTION IN THE KSUX TAF AT THIS TIME.

&&

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

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1127 AM CDT WED JUL 25 2012

SDZ038>040-050-052>071-MNZ071-072-080-081-089-090-097-098-
IAZ001>003-012>014-020>022-031-032-NEZ013-014-261200-
AURORA-BEADLE-BON HOMME-BROOKINGS-BRULE-BUENA VISTA IA-
CHARLES MIX-CHEROKEE IA-CLAY-CLAY IA-COTTONWOOD MN-DAKOTA NE-
DAVISON-DICKINSON IA-DIXON NE-DOUGLAS-GREGORY-HANSON-HUTCHINSON-
IDA IA-JACKSON MN-JERAULD-KINGSBURY-LAKE-LINCOLN-LINCOLN MN-
LYON IA-LYON MN-MCCOOK-MINER-MINNEHAHA-MOODY-MURRAY MN-NOBLES MN-
OBRIEN IA-OSCEOLA IA-PIPESTONE MN-PLYMOUTH IA-ROCK MN-SANBORN-
SIOUX IA-TURNER-UNION-WOODBURY IA-YANKTON-
1127 AM CDT WED JUL 25 2012

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEAST SOUTH DAKOTA...
SOUTHWEST MINNESOTA...NORTHWEST IOWA...AND NORTHEAST NEBRASKA.

.DAY ONE...TODAY AND TONIGHT

THUNDERSTORMS...
THERE IS A SLIGHT CHANCE OF THUNDERSTORMS ACROSS SOUTHEAST SOUTH
DAKOTA AND SOUTHWEST MINNESOTA THROUGH WEDNESDAY AFTERNOON. A
SLIGHTLY BETTER CHANCE FOR STORMS IS POSSIBLE MAINLY ACROSS
NORTHWEST IOWA LATE THIS AFTERNOON AND EARLY EVENING BEFORE THE
STORMS MOVE EAST OF THE AREA. AN ISOLATED STORM COULD PRODUCE
WIND GUSTS TO 50 MPH...MAINLY IN NORTHWEST IOWA...BUT SEVERE
WEATHER IS NOT EXPECTED.

EXCESSIVE TEMPERATURES...
HEAT INDEX VALUES WILL BE CLOSE TO 100 DEGREES THIS AFTERNOON
AROUND THE SIOUX CITY AND STORM LAKE IOWA AREAS.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

ISOLATED NON SEVERE THUNDERSTORMS WILL BE POSSIBLE THURSDAY
AFTERNOON AND EARLY EVENING ACROSS SOUTHWEST MINNESOTA.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION SHOULD NOT BE NEEDED TODAY AND TONIGHT.

&&

FOR MORE INFORMATION PLEASE VISIT OUR WEBSITE AT
WWW.WEATHER.GOV/SIOUXFALLS. THIS INCLUDES THE GRAPHICAL HAZARDOUS
WEATHER OUTLOOK.