Severe Thunderstorm Warning 117, NWS Sioux Falls, SD

833 
WWUS53 KFSD 260946
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
446 AM CDT SAT MAY 26 2012

SDC053-260956-
/O.CAN.KFSD.SV.W.0117.000000T0000Z-120526T1000Z/
GREGORY SD-
446 AM CDT SAT MAY 26 2012

...THE SEVERE THUNDERSTORM WARNING FOR NORTH CENTRAL GREGORY COUNTY
IS CANCELLED...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE WARNED 
AREA.

LAT...LON 4367 9892 4353 9879 4350 9880 4350 9876
      4346 9872 4339 9885 4339 9886 4357 9905
TIME...MOT...LOC 0946Z 230DEG 35KT 4352 9887

$$

SDC015-023-261000-
/O.CON.KFSD.SV.W.0117.000000T0000Z-120526T1000Z/
CHARLES MIX SD-BRULE SD-
446 AM CDT SAT MAY 26 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR SOUTHEASTERN
BRULE AND NORTH CENTRAL CHARLES MIX COUNTIES UNTIL 500 AM CDT...

AT 446 AM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE TRACKING
A SEVERE THUNDERSTORM CAPABLE OF PRODUCING HALF DOLLAR SIZE HAIL...
AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED 8
MILES NORTHWEST OF PLATTE...OR 18 MILES SOUTH OF KIMBALL...MOVING
NORTHEAST AT 40 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 4367 9892 4353 9879 4350 9880 4350 9876
      4346 9872 4339 9885 4339 9886 4357 9905
TIME...MOT...LOC 0946Z 230DEG 35KT 4352 9887
WIND...HAIL 60MPH 1.25IN

$$

CHENARD

610 
WWUS53 KFSD 261001
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
501 AM CDT SAT MAY 26 2012

SDC015-023-261012-
/O.EXP.KFSD.SV.W.0117.000000T0000Z-120526T1000Z/
CHARLES MIX SD-BRULE SD-
501 AM CDT SAT MAY 26 2012

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN BRULE AND NORTH
CENTRAL CHARLES MIX COUNTIES HAS EXPIRED...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE WARNED
AREA.

LAT...LON 4367 9892 4353 9879 4350 9880 4350 9876
      4346 9872 4339 9885 4339 9886 4357 9905
TIME...MOT...LOC 0946Z 230DEG 35KT 4351 9886

$$

CHENARD

AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NATIONAL WEATHER SERVICE SIOUX FALLS SD
406 AM CDT SAT MAY 26 2012

.DISCUSSION.../ISSUED AT 406 AM CDT/
WILL GIVE A FAIRLY BRIEF DISCUSSION WITH THE ONGOING CONVECTION
CONCERNS...WITH MOST OF THE WEATHER CHALLENGES CONFINED TO THIS
WEEKEND ANYWAY. CURRENTLY...VERY STRONG WARM FRONT ALOFT WITH
ASSOCIATED STRONG THETA E ADVECTION CONTINUES TO LIFT NORTHWARD
SPARKING SCATTERED THUNDERSTORMS. AS THE STORMS MOVE NORTHWARD...
THERE ARE STILL INDICATIONS THAT THE ACTIVITY WILL COALESCE AND FILL
IN PRIMARILY NORTH OF I 90 WHERE THE STRONG INTERACTION WITH THE
850MB FRONT IS. THEREFORE EARLY THIS MORNING...CONTINUED THE TREND
OF GOING HIGH POPS FOR AREAS NORTH OF I 90...BUT ONLY TIME WILL TELL
HOW MUCH THE CONVECTION FILLS IN ACROSS SW MINNESOTA. WITH VERY HIGH
ELEVATED CAMPS AND STRONG WIND SHEAR...AN ISOLATED SEVERE STORM IS
POSSIBLE EARLY TODAY. THEN DURING THE MIDDAY HOURS IS WHEN WE MAY
FIND A BREAK IN THE ACTION. BUT LATE THIS AFTERNOON AND EARLY
EVENING IS CONCERNING. MASSIVE ML CAPE VALUES EXCEEDING 2000 J/KG
ARE EVIDENT ON MULTIPLE MODELS LATE TODAY. IN ADDITION...THE NEXT
STRONG ROUND OF 700MB THETA E ADVECTION MOVES NORTHWARD AND WITH THE
AMOUNT OF SURFACE HEATING  EXPECTED SOUTH OF THE 850MB FRONT...THE
CAP COULD VERY WELL BREAK. BOTH THE NAM...ECMWF AND THE GEM REGIONAL
HINT AT THE STRONGEST CONVECTION BEING IN A BAND FROM YANKTON TO
SIOUX CITY... NORTHEASTWARD THROUGH THE SIOUX FALLS AREA AND INTO SW
MINNESOTA. TIMING WISE IS FOR THE VERY LATE AFTERNOON AND EVENING
HOURS. THIS IS A SUPERCELL TYPE SITUATION WITH LARGE HAIL AND
DAMAGING WINDS...DEEP LAYER VEERING WIND SHEAR AND 0-3KM BULK SHEAR
VECTORS A STRONG 45 TO 50 KNOTS THROUGH THIS AREA. BUT THE ACTIVITY
WILL LIKELY BE OF A SCATTERED NATURE. CONCERNING TEMPERATURES...WITH
THE WARM FRONT LIFTING A BIT FURTHER NORTHWARD THAN PREVIOUSLY
THOUGHT...WARMED UP SOME MAX TEMPERATURES FOR TODAY ALONG THE I 90
CORRIDOR AND THROUGH OUR NORTHERN ZONES.

LATE SUNDAY AND SUNDAY EVENING IS WHEN THE NEXT MAJOR ACTION WILL
TAKE PLACE...WITH OUR WELL ADVERTISED VERY STRONG MID LEVEL IMPULSE
RIDING NORTHEASTWARD JUST AHEAD OF A SURFACE COLD FRONT. ALL MODELS
CONTINUE TO INITIATE CONVECTION AS THEY HAVE BEEN FOR SEVERAL DAYS
NOW...PRIMARILY ALONG AND EAST OF A TYNDALL SD TO BROOKINGS SD LINE.
MENTIONED A CHANCE FOR SEVERE WEATHER IN THE VERY LATE AFTERNOON AND
EVENING. DIRECTIONAL SHEAR IS NOT AS IMPRESSIVE ON SUNDAY AS IT IS
TODAY...BUT THE SPEED SHEAR REMAINS VERY STRONG WITH 60 TO 65 KNOTS
WIDESPREAD AT 6KM.

&&

.AVIATION.../FOR THE 06Z TAF ISSUANCE/
THUNDERSTORMS ACROSS NORTHEAST NEBRASKA WILL BUILD NORTHEAST INTO
EXTREME SOUTHEAST SOUTH DAKOTA AND NORTHEAST IOWA THROUGH AROUND 08Z
BEFORE EXITING FROM THE FORECAST AREA. BEHIND THIS LINE...A SECOND
LINE OF THUNDERSTORMS WILL DEVELOP NEAR THE MISSOURI RIVER AROUND
09Z AND TRACK NORTHEASTWARD THROUGH AROUND 15Z. THE MAIN THREAT FOR
SEVERE WEATHER WILL BE HAIL TO HALF DOLLAR SIZE AND LOCALIZED STRONG
WIND GUSTS MAINLY SOUTH OF I90 IN THE EARLY MORNING HOURS. IN
THUNDERSTORMS...CEILINGS AND VISIBILITY WILL DROP INTO MVFR AND IFR
CATEGORIES...WITH CEILINGS LIKELY TO BECOME PREDOMINATE AT AROUND
1000 TO 3000 FEET FROM 12Z AROUND 15Z WITH SHOWERS AND ISOLATED
THUNDERSTORMS LINGERING. CEILINGS WILL GRADUALLY LIFT TO VFR AFTER
15Z.

&&

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

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SIOUX FALLS SD
920 PM CDT FRI MAY 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-
920 PM CDT FRI MAY 25 2012

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

.DAY ONE...TODAY AND TONIGHT

THUNDERSTORMS...
THUNDERSTORMS DEVELOPING ACROSS NEBRASKA ARE EXPECTED TO SPREAD
NORTH INTO THE AREA AFTER MIDNIGHT. A FEW OF THESE STORMS COULD
BECOME SEVERE WITH QUARTER TO HALF DOLLAR SIZE HAIL...MAINLY
ALONG AND SOUTH OF INTERSTATE 90.

FLOODING...
RIVER RISES FROM HEAVY RAIN WEDNESDAY NIGHT ARE NOW EXPECTED TO
BE TO LESS THAN FLOOD STAGE...EXCEPT FOR THE LITTLE SIOUX RIVER
AT LINN GROVE...WHICH IS EXPECTED TO CREST SLIGHTLY ABOVE FLOOD
STAGE SUNDAY.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

SCATTERED THUNDERSTORMS ARE POSSIBLE SATURDAY MORNING...MAINLY
NORTH OF INTERSTATE 90...AND A FEW OF THESE COULD BE SEVERE. LATE
SATURDAY AFTERNOON AND EARLY SATURDAY EVENING A FEW THUNDERSTORMS
COULD DEVELOP...WITH THE BEST CHANCE ACROSS SOUTHWEST MINNESOTA.
THESE THUNDERSTORMS COULD BECOME SEVERE WITH HAIL TO THE SIZE OF
GOLF BALLS...WIND GUSTS TO 70 MPH AND TORNADOES ALL A THREAT.

ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS ARE LIKELY LATE SUNDAY
AFTERNOON INTO THE OVERNIGHT HOURS. THE BEST CHANCE WILL BE EAST
OF THE JAMES RIVER. SOME OF THESE STORMS COULD AGAIN BE SEVERE
WITH HEAVY RAIN ALSO POSSIBLE.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL BE POSSIBLE AFTER MIDNIGHT OR 1 AM MAINLY
SOUTH OF INTERSTATE 90.

&&

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