Severe Thunderstorm Warning 107, NWS Sioux Falls, SD

967 
WWUS53 KFSD 230303
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1003 PM CDT TUE MAY 22 2012

SDC005-230315-
/O.CON.KFSD.SV.W.0107.000000T0000Z-120523T0315Z/
BEADLE SD-
1003 PM CDT TUE MAY 22 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR CENTRAL BEADLE
COUNTY UNTIL 1015 PM CDT...

AT 1002 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE
TRACKING A SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN
EXCESS OF 60 MPH.  THIS STORM WAS LOCATED 8 MILES NORTH OF HURON...
MOVING NORTHEAST AT 45 MPH.

AT 957 PM CDT...WEATHER SPOTTERS REPORTED A 45 MPH WIND GUST IN 
BROADLAND.

ALTHOUGH THIS STORM IS BEGINNING TO WEAKEN...IT IS STILL CAPABLE OF 
PRODUCING WIND GUSTS TO 60 MPH.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60 MILES PER
HOUR...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN. FOR
YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR
HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE
INTO AREAS WHERE WATER COVERS THE ROAD.

&&

LAT...LON 4451 9801 4438 9841 4448 9847 4463 9829
TIME...MOT...LOC 0302Z 238DEG 37KT 4448 9826
WIND...HAIL 60MPH <1.00IN

$$

SCHUMACHER

613 
WWUS53 KFSD 230308
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1008 PM CDT TUE MAY 22 2012

SDC005-230318-
/O.EXP.KFSD.SV.W.0107.000000T0000Z-120523T0315Z/
BEADLE SD-
1008 PM CDT TUE MAY 22 2012

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL BEADLE COUNTY WILL
EXPIRE AT 1015 PM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR 
PROPERTY...HOWEVER GUSTY WINDS UP TO 50 MPH ARE STILL POSSIBLE WITH 
THESE SHOWERS AND STORMS.

LAT...LON 4451 9801 4438 9841 4448 9847 4463 9829
TIME...MOT...LOC 0308Z 238DEG 37KT 4451 9819

$$

SCHUMACHER

AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NATIONAL WEATHER SERVICE SIOUX FALLS SD
902 PM CDT TUE MAY 22 2012

.DISCUSSION.../ISSUED AT 900 PM CDT/
MAIN ISSUE OVER THE NEXT 18 HOURS IS THE CONVECTIVE CHANCES WITH THE
SURFACE COLD FRONT. CURRENTLY A BROKEN LINE OF CONVECTION EXTENDS
FROM NEAR ABERDEEN TO WINNER SOUTH DAKOTA. WHILE STORMS INITIALLY
DEVELOPED ALONG THE SURFACE FRONT...THE STRONG LOW LEVEL WINDS HAVE
RESULTED IN STORM MOTIONS THAT MOVE THEM AWAY FROM THE BOUNDARY.  AS
A RESULT...UPDRAFTS CONTINUE TO WEAKEN ONCE THE STORMS MOVE INTO THE
MORE STABLE AIR MASS OVER SOUTHEAST SOUTH DAKOTA. WITH LITTLE UPPER
LEVEL FORCING FOR ASCENT IN THE NEXT HOUR OR TWO...SEVERE WEATHER
APPEARS UNLIKELY ALTHOUGH WITH 60 KT WINDS AT 850 MB...A SEVERE WIND
GUST OR QUARTER SIZE HAIL MAY STILL BE POSSIBLE.

EXPECTATION IS THESE STORMS WILL LIKELY SLOWLY WEAKEN OVER NEXT 3 OR
4 HOURS...ESPECIALLY SOUTH OF I-90 WHERE LOSS OF SURFACE HEATING
WILL ONLY STRENGTHEN CAP. HOWEVER...BOTH RAP AND NAM SHOW ANOTHER
WEAK WAVE WITH ASSOCIATED COOLING AT MID LEVELS MOVING INTO CENTRAL
SD AROUND 09Z. THESE MODELS ALONG WITH HRRR ALL PRODUCE MORE
CONVECTION AHEAD THE SURFACE COLD FRONT WHICH IS EXPECTED TO BE
BETWEEN 9V9 AND MHE. WITH THE COLD ADVECTION AND WEAK MIDLEVEL
ASCENT...THIS IS EXPECTED TO BE ENOUGH TO ERODE THE CAP AHEAD OF THE
LATER TONIGHT. AM A LITTLE CONCERNED THAT MODELS MAY BE OVERDOING
THE DEGREE OF COOLING ABOVE THE INVERSION AND CONVECTION WILL BE A
LITTLE LESS WIDESPREAD THAN MODELS ARE SHOWING...ESPECIALLY SOUTH OF
I90. BECAUSE THIS SECOND WAVE IS LATER IN THE NIGHT...HAVE SLOWED
THE PROGRESSION OF PRECIPITATION OVERNIGHT INTO WEDNESDAY MORNING
WITH THE BEST CHANCE FOR STORMS REMAINING OVER EAST CENTRAL SD
THROUGH 12Z AND THEN IN SW MN THROUGH 15Z OR 18Z. ALSO RAISED POPS
ALONG AND NORTH I90 LATE TONIGHT TO 30 TO 50 PERCENT RANGE.
FINALLY...HAVE INCREASED QPF OVERNIGHT TO AN AVERAGE OF 0.1 TO 0.2
ALONG HWY 14 ALTHOUGH LOCAL AMOUNTS APPROACHING 0.5 IN ARE POSSIBLE
WITH STORMS...AROUND BKX AND MML.

MADE FEW CHANGES TO TEMPERATURES OR WIND BUT DID INCREASE SKY COVER
THIS EVENING. LATEST GRID/ZFP AND PFM ALREADY ISSUED.
&&

.AVIATION.../FOR THE 00Z TAF ISSUANCE/
MAINLY VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD. STRONG
SOUTHERLY WIND GUSTS AROUND 30-35KTS EXPECTED TO PERSIST THROUGH
EARLY PART OF TAF PERIOD...THOUGH EVEN AFTER 03Z GUSTS AROUND 25KT
WILL REMAIN LIKELY UNTIL COLD FRONT APPROACHES FROM THE WEST LATER
TONIGHT...ALLOWING FOR WEAKENING SURFACE GRADIENT/FURTHER DECREASE
IN WINDS. MODELS CONTINUE TO SHOW 50-60KT LOW LEVEL JET ABOVE 1500FT
AGL...LEADING TO CONCERNS OF LOW LEVEL WIND SHEAR. ALTHOUGH WINDS
REMAIN SOMEWHAT GUSTY AT THE SURFACE...WITH LOW LEVEL JET OF THIS
MAGNITUDE AND DIRECTION SLIGHTLY VEERED FROM DOMINANT SURFACE WIND
DIRECTION...WILL CONTINUE MENTION OF LLWS FOR ALL TAF LOCATIONS
TONIGHT. CONFIDENCE IN ELEVATED THUNDERSTORMS AFFECTING TAF SITES
OVERNIGHT IS WANING...AS UPPER LEVEL SUPPORT SEEMS TO FOCUS MORE TO
THE NORTH OF THIS AREA. WILL HANG ONTO A SMALL WINDOW OF POSSIBLE
TSRA FOR KHON 06Z-08Z AS SECONDARY MID LEVEL WAVE MOVES INTO THE
AREA. OTHERWISE KEEPING THE TAFS FREE OF PRECIPITATION THROUGH
WEDNESDAY. CHANCES WILL INCREASE LATE IN THE PERIOD ALONG AND EAST
OF I-29 CORRIDOR AS COLD FRONT PUSHES SLOWLY EAST. HOWEVER...THINK
CAPPING INVERSION AHEAD OF THE COLD FRONT COULD SUPPRESS CONVECTION
UNTIL AFTER THE END OF THIS TAF PERIOD AND OPTED TO LEAVE POTENTIAL
LATE AFTERNOON TSRA OUT OF THIS ISSUANCE.

&&
.PREV DISCUSSION.../ISSUED AT 330 PM CDT/
STRONG SOUTHERLY FLOW CONTINUES ACROSS THE AREA AHEAD OF A COLD
FRONT THAT HAS PUSHED INTO FAR NORTHWEST CORNER OF SOUTH DAKOTA.
WITH GRADIENT CONTINUING TO STRENGTHEN ALOFT...WILL CONTINUE WIND
ADVISORY ACROSS THE AREA THROUGH THE EVENING HOURS AS THE FRONT
WORKS EAST THIS EVENING...COULD SEE THUNDERSTORMS DEVELOP BUT EXPECT
THE FOCUS TO BE FURTHER NORTH CLOSER TO THE MID LEVEL WAVE.  AS
SUCH...HAVE NOT MADE MANY ADJUSTMENTS TO POPS WITH FOCUS MAINLY
NORTH OF I-90.  WITH STOUT WINDS CONTINUING AHEAD OF THE
FRONT...KEPT FORECAST LOWS QUITE MILD CLOSER TO CONS RAW AND W MODEL.

BOUNDARY IS EXPECTED TO ENTER THE FORECAST AREA AFTER 06Z WEDNESDAY
AND SLOWLY PUSH EAST.  NOT A LOT IN TERMS OF UPPER LEVEL SUPPORT
UNTIL WEDNESDAY EVENING AS UPPER WAVE LIFTS INTO THE REGION...AND
WEAK CAPPING INVERSION LOOKS TO HOLD FOR THE BETTER PART OF THE
DAY.  KEPT CHANCE POPS GOING IN THE VICINITY OF THE FRONT THROUGH
THE DAY...BUT FOCUS WILL CERTAINLY BE WEDNESDAY NIGHT.  HIGHS WILL
GENERALLY BE IN THE 70S TO LOWER 80S WITH 850 HPA TEMPS IN THE MID
TEENS.

CONTINUES TO LOOK LIKE A POTENTIAL HEAVY RAIN EVENT WEDNESDAY NIGHT
INTO EARLY THURSDAY MORNING AS FRONT STALLS ACROSS FAR SOUTHEAST CWA
WEDNESDAY NIGHT INTO THURSDAY MORNING WHILE WAVE EJECTS NORTHEAST OUT
OF NEBRASKA. INITIALLY COULD SEE SOME SEVERE WEATHER DURING THE
EVENING ACROSS NORTHWEST IOWA...BUT MAIN CONCERN WOULD BE THE HEAVY
RAINS. MODELS DO DIFFER ON PLACEMENT WITH GFS AND EC A LITTLE
FURTHER SOUTH THAN NAM/GEM. PREFER THE GFS/EC SOLUTION WITH BEST
CHANCE CLOSER TO FRONT WHERE DEEP MOISTURE WILL POOL AND WHERE
HIGHEST PWATS NEAR 1.50 INCHES EXPECTED. SO ACTIVITY THAT DEVELOPS
IN THE AFTERNOON SHOULD REALLY GET GOING WEDNESDAY EVENING AND
PERSIST THROUGH THE NIGHT WITH LOCAL RAINFALL AMOUNTS OVER 3 INCHES
LIKELY ESPECIALLY NEAR THE FRONT AND THEN DROPPING OFF DRAMATICALLY
ACROSS FAR NORTHWEST CWA. SO HIGHEST POPS WILL BE ACROSS SOUTHEAST
CWA WEDNESDAY NIGHT INTO THURSDAY MORNING...AND THEN A LINGERING
SMALLER CHANCE THURSDAY AFTERNOON IN EARLY EVENING. WILL HOLD OFF
ANY FLOOD WATCH FOR WEDNESDAY NIGHT...DUE TO UNCERTAINTY ON EXACT
LOCATION OF HEAVIEST RAIN...BUT WILL MENTION HEAVY RAIN IN GRIDS
ACROSS SOUTHEAST CWA AND ALSO MENTIONED IN HWO.

ON FRIDAY...BOUNDARY ACROSS SOUTHERN NEBRASKA AND SOUTHERN IOWA WILL
BEGIN TO LIFT SLOWLY NORTH FRIDAY NIGHT INTO SATURDAY...REACHING I90
ON SATURDAY. SO AS THIS FRONT LIFTS NORTH WOULD EXPECT AT LEAST
SCATTERED THUNDERSTORMS TO DEVELOP ON EDGE OF MID LEVEL CAP AS LOW
LEVEL JET INCREASES DURING THE NIGHT AND WAVE LIFTS NORTHEAST OUT OF
WESTERN NEBRASKA. COULD SEE ELEVATED SEVERE STORMS LATER IN THE
NIGHT AS THIS FRONT LIFTS NORTH.

WITH FRONT ALONG I90 ON SATURDAY...BEST CHANCE FOR THUNDERSTORMS
WILL CONTINUE NORTH OF I90 THROUGH SATURDAY...WITH POTENTIAL FOR
MORE HEAVY RAIN...THIS TIME ACROSS NORTHERN CWA SATURDAY NIGHT. WILL
HIGHLY DEPEND ON LOCATION OF MID LEVEL CAP AND FRONT AND HEAVIEST
RAIN COULD FALL NORTH OF CWA. SO WILL HAVE HIGHEST POPS ACROSS
NORTHERN CWA AND FAR SOUTHERN CWA MAY NOT SEE ANYTHING AFTER
CONVECTION LIFTS NORTH SATURDAY MORNING. VERY HIGH CAPES SOUTH OF
BOUNDARY IN CAPPED AIR OVER NORTHWEST IOWA...BUT DEFINATELY
SOMETHING TO WATCH NORTH OF BOUNDARY LATE SATURDAY AFTERNOON AND
EVENING FOR A ROUND OF SEVERE WEATHER.

AS WE HEAD INTO SUNDAY...COLD FRONT WILL PUSH EAST ACROSS CWA SUNDAY
AFTERNOON AND NIGHT WITH YET ANOTHER ROUND OF THUNDERSTORMS. IF MID
LEVEL CAP CAN BREAK AHEAD OF THIS FRONT WHICH GFS AND EC HINTING
AT...COULD SEE SOME SEVERE WEATHER IN THE AFTERNOON AND EVENING
ACROSS THE EASTERN CWA.

MEMORIAL DAY LOOKS TO BE QUIET AND DRY AND WILL CONTINUE THAT TREND
INTO TUESDAY.

TEMPERATURES WILL BE ON A ROLLER COASTER THURSDAY THROUGH
SUNDAY...WITH COOLER TEMPERATURES IN THE UPPER 60S TO MID 70S
THURSDAY AND FRIDAY AND THEN AS FRONT LIFTS NORTH...HIGHS ON
SATURDAY WILL LIKELY VARY FROM NEAR 70 ACROSS THE FAR NORTH TO NEAR
90 FAR SOUTHEAST. SHOULD BE WARMER ACROSS ALL OF CWA ON SUNDAY AHEAD
OF FRONT WITH HIGHS IN THE 80S...AND THEN COOLING BACK INTO 70S
MONDAY AND TUESDAY.

&&

.AVIATION.../FOR THE 00Z TAF ISSUANCE/
MAINLY VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD. STRONG
SOUTHERLY WIND GUSTS AROUND 30-35KTS EXPECTED TO PERSIST THROUGH
EARLY PART OF TAF PERIOD...THOUGH EVEN AFTER 03Z GUSTS AROUND 25KT
WILL REMAIN LIKELY UNTIL COLD FRONT APPROACHES FROM THE WEST LATER
TONIGHT...ALLOWING FOR WEAKENING SURFACE GRADIENT/FURTHER DECREASE
IN WINDS. MODELS CONTINUE TO SHOW 50-60KT LOW LEVEL JET ABOVE 1500FT
AGL...LEADING TO CONCERNS OF LOW LEVEL WIND SHEAR. ALTHOUGH WINDS
REMAIN SOMEWHAT GUSTY AT THE SURFACE...WITH LOW LEVEL JET OF THIS
MAGNITUDE AND DIRECTION SLIGHTLY VEERED FROM DOMINANT SURFACE WIND
DIRECTION...WILL CONTINUE MENTION OF LLWS FOR ALL TAF LOCATIONS
TONIGHT. CONFIDENCE IN ELEVATED THUNDERSTORMS AFFECTING TAF SITES
OVERNIGHT IS WANING...AS UPPER LEVEL SUPPORT SEEMS TO FOCUS MORE TO
THE NORTH OF THIS AREA. WILL HANG ONTO A SMALL WINDOW OF POSSIBLE
TSRA FOR KHON 06Z-08Z AS SECONDARY MID LEVEL WAVE MOVES INTO THE
AREA. OTHERWISE KEEPING THE TAFS FREE OF PRECIPITATION THROUGH
WEDNESDAY. CHANCES WILL INCREASE LATE IN THE PERIOD ALONG AND EAST
OF I-29 CORRIDOR AS COLD FRONT PUSHES SLOWLY EAST. HOWEVER...THINK
CAPPING INVERSION AHEAD OF THE COLD FRONT COULD SUPPRESS CONVECTION
UNTIL AFTER THE END OF THIS TAF PERIOD AND OPTED TO LEAVE POTENTIAL
LATE AFTERNOON TSRA OUT OF THIS ISSUANCE.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
IA...WIND ADVISORY FROM 10 AM TO 8 PM CDT TUESDAY FOR IAZ001>003-
     012>014-020>022-031-032.

MN...WIND ADVISORY FROM 10 AM TO 8 PM CDT TUESDAY FOR MNZ071-072-080-
     081-089-090-097-098.

NE...WIND ADVISORY FROM 10 AM TO 8 PM CDT TUESDAY FOR NEZ013-014.

SD...WIND ADVISORY FROM 10 AM TO 8 PM CDT TUESDAY FOR SDZ038>040-050-
     052>071.

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SIOUX FALLS SD
222 PM CDT TUE MAY 22 2012

SDZ038>040-050-052>071-MNZ071-072-080-081-089-090-097-098-
IAZ001>003-012>014-020>022-031-032-NEZ013-014-231200-
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-
222 PM CDT TUE MAY 22 2012

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

.DAY ONE...TODAY AND TONIGHT

THUNDERSTORMS...
THUNDERSTORMS ARE EXPECTED TO DEVELOP IN NORTH CENTRAL SOUTH
DAKOTA LATE THIS AFTERNOON AND MOVE EAST OVERNIGHT. A FEW STORMS
COULD BE SEVERE NEAR THE MID JAMES VALLY WITH QUARTER SIZED HAIL
AND WIND GUSTS TO 60 MPH. OTHERWISE ANY ACTIVITY THAT OCCURS
OVERNIGHT SHOULD REMAIN BELOW SEVERE LIMITS.

WIND...
SOUTH WINDS OF 30 TO 40 MPH WILL CONTINUE THIS AFTERNOON OVER THE
ENTIRE AREA.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

THUNDERSTORMS ARE EXPECTED TO DEVELOP ON WEDNESDAY AFTERNOON OVER
NORTHWEST IOWA. A FEW OF THESE STORMS COULD BECOME SEVERE WITH
HALF DOLLAR SIZED HAIL AND WIND GUSTS TO 70 MPH POSSIBLE.
HOWEVER...THE MAIN THREAT FROM THESE THUNDERSTORMS WILL BE HEAVY
RAINFALL ON WEDNESDAY NIGHT. THE HIGHEST THREAT FOR HEAVY RAIN
WILL BE FROM NEAR YANKTON TO SIOUX FALLS TO MARSHALL INTO PARTS
OF NORTHWEST IOWA WHERE A FEW LOCATIONS COULD RECEIVE AROUND 3
INCHES OF RAINFALL.

THERE IS A CHANCE FOR THUNDERSTORMS FRIDAY AND SATURDAY. A FEW OF
THESE STORMS COULD BECOME SEVERE.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL BE POSSIBLE AFTER 800 PM CDT IN CENTRAL
SOUTH DAKOTA.

&&

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