Alert archive / South Dakota / Flash Flood Warnings in 2010

Flash Flood Warning 33, NWS Sioux Falls, SD

July 10, 2010Davison County, Hanson County, South Dakota

NWS Sioux Falls, SD issued this flash flood warning at Jul 10, 2010, 7:48 PM CDT for Davison County, Hanson County, South Dakota. It was in force for 87 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jul 10, 2010, 7:48 PM CDT (00:48 UTC)
Expired
Jul 10, 2010, 9:15 PM CDT
In force
87 min
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Flood severity
None

Counties Davison County, SD, Hanson County, SD

The radar

The Sioux Falls radar (KFSD), 100 km from the middle of the area, began a volume at 00:51 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Aberdeen, SD (KABR), launched 00:00Z, 0.8 hours before the alert went out and 141 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Aberdeen, SD at 00:00Z on 2010-07-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1200 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Aberdeen, SD at 00:00Z on 2010-07-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 10 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
1200 J/kg
Mixed-layer CIN
-96 J/kg
Mixed-layer LCL
2383 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
10 m²/s²
0-3 km storm-relative helicity
40 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.9

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Sioux Falls, SD wrote its last area forecast discussion before this flash flood warning went out at Jul 10, 4:15 PM CDT, 3 hours 33 minutes earlier.

Area forecast discussion, Jul 10, 4:15 PM CDT, 3 hours 33 minutes before
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NATIONAL WEATHER SERVICE SIOUX FALLS SD
415 PM CDT SAT JUL 10 2010

.DISCUSSION...
CWA CURRENTLY IN WAKE OF WAVE WHICH HAS PUSHED OFF E THRU MN...
AND AHEAD OF NEXT UPSTREAM WAVE PUSHING OUT OF WY INTO SWRN SD.
INCREASE IN LLJ AHEAD OF SECOND WAVE HAS BROUGHT SOME HEALTHY BL
DWPTS NWRD...BUT ALSO NOW HAVE DRYLINE JUST W OF THE CWA WITH 68
DWPT AT K9V9...AND DOWN TO 53 AT KICR. A COUPLE CELLS RECENTLY
DEVELOPED IN SCNTRL SD ALG BOTH WIND SHIFT SE OF KPIR...AND ALG
THE DRYLINE IN TRIPP/LYMAN CNTY BORDER AREA. SVR THREAT FOR THE
OVERNIGHT IS THE PRIMARY FOCUS.

STILL HAVE PRESENCE OF STRONG ELEVATED MIXED LAYER ACRS THE AREA
THIS AFTN...BUT ACTIVITY HAS BEEN SHUT DOWN BY THE WK SUBSIDENCE
IN WAKE OF EARLIER WAVE. HOWEVER...WITH PRESENCE OF DEEPER MOISTURE
STREAMING THRU CWA...HAVE DESTABILIZED WITH ML CAPE OF 2000-3000
J/KG...AND CAP LACKING NORMAL STOUTNESS. THEREFORE...EXPECT THAT WL
ONLY TAKE A BETTER FAVOR TOWARD LIFT FORCING TO GET CONVECTION GOING
NEAR EXISTING BOUNDARIES. EFFECTIVE SHEAR SUGGESTS THAT ROTATING
STORMS WL BE PROBABLE...BUT MIXING TO THE W WL CREATE SITUATION OF
HIGHER LCL TO START WITH FOR THIS EVENING FOR THE WRN STORMS. BETTER
TOR PARAMETERS ARE DEFINITELY TO THE EAST OF THE EXISTING WATCH...
BUT EVEN THOSE WL TAKE A HIT WITH WKNG WINDS THIS EVENING BY THE
TIME CONVECTION WORKS THAT FAR EWRD.  WITH SUPERCELLULAR STRUCTURES
LATE AFTN/EARLY EVNG...FORWARD MOTION SLOWS TO A CRAWL...7-11 KTS
BASED ON EXPECTED WIND STRUCTURE. THESE STORMS COULD POTENTIALLY
TAKE ON HP CHARACTERISTICS AT THIS POINT... PRODUCING VERY LARGE
HAIL AND DAMAGING WIND GUSTS. AS STORMS BUILD EWRD LATER IN THE
EVENING AND OVERNIGHT...WOULD EXPECT TRANSITION TO MULTICELL
STRUCTURES...FEATURING SHORT BOWING SEGMENTS...AND SOMEWHAT LARGER
HAIL AND DAMAGING WIND THREAT TOWARD I29 CORRIDOR...THEN MOSTLY JUST
DAMAGING WINDS ACRS NW IA. /CHAPMAN

EXPCD MCS PULLS ESEWD THRU NWRN IA EARLY IN THE MRNG FLWD BY SOME
ACCAS LEFTOVERS REST OF SE CWA IN THE MRNG. CDFNT GRADUALLY MOVES
SEWD OVER CWA DURG DAY...BUT MOST DYNAMICS AND INSTABILITY ASSCD
WITH EARLY MRNG MCS. HOWEVER...WILL KEEP POPS IN THE AFTN SERN HLF
CWA WITH BOUNDARY MOVG THRU AND ENUF DESTABILIZATION. IF THERE ARE
ANY SVR TSTMS...IT WILL PROBABLY BE SE OF LN FM MJQ TO SUX WITH FNT
PER SPC. SYSTEM PULLS OUT BY SUN EVE...BUT NOW MODELS PRETTY GUNGHO
WITH RETURN LWR TO MID LVL FLOW ASSCD WITH NEW SHORT WAVE PUNCHING
EAST. WILL EXPAND POPS NWD OVER SRN CWA TO VCNTY I90 LATER SUN NGT
THRU MON WITH THIS WAVE...BUT GFS OVERDONE WITH BULLEYE QPF COMPARED
TO OTHER MODELS WHICH ARE MUCH WEAKER AND FURTHER SOUTH. SUN THRU
MON WILL BE RELATIVELY COOLER WITH CLOUDS AND SOME RAIN COOLED AIR
EXPCD...BUT LOW LVL MOISTURE SHOULD LINGER WITH HIGHER DEWPOINTS
THAN PREV FCST. NEXT DECENT CHC TSTMS WILL START NORTH OF I90 LATER
TUES NGT AHEAD OF NEXT BIG SHORT WAVE IN NRN PLAINS...THEN DVLP SEWD
THRU ERN HLF CWA WED...LINGERING IN FAR SERN CWA WED EVE NEAR CDFNT.
SLY FLOW SHOULD BRING BACK VERY WARM AND HUMID AIR INTO CWA ON
TUES...SHIFTING SE OF AREA LATE WED WITH FNT. THU INTO FRI SHOULD BE
NICE DAYS...PLEASANT ON THU AND WARMING UP AGAIN FRI WITH RETURN SLY
FLOW. PUT IN SLGT CHC TSTMS SWRN CWA FRI AFTN AND SRN AND ERN CWA
FRI NGT WITH EXPCD MID LVL WAVE. /RYRHOLM

&&

.AVIATION...
WIDESPREAD VFR CONDITIONS LATE AFTN WL BECOME GRADUALLY INTERSPERSED
WITH CONVECTIVE REDUCTION TO MVFR CIGS/IFR-MVFR VSBYS. CONVECTION
SHUD BE SCT AS IT PUSHES INTO KHON AREA EARLY EVNG...AND TOWARD/AFT
MIDNIGHT FOR KFSD/KSUX AREAS. STORMS ESPLY THRU THE JAMES VALLEY AND
WWRD THIS EVENING WL BE CAPABLE OF VERY LARGE HAIL.  /CHAPMAN

&&

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

&&
Hazardous weather outlook, Jul 10, 11:54 AM CDT, 7 hours 54 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1154 AM CDT SAT JUL 10 2010

SDZ038>040-050-052>071-MNZ071-072-080-081-089-090-097-098-
IAZ001>003-012>014-020>022-031-032-NEZ013-014-111200-
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-
1154 AM CDT SAT JUL 10 2010

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

.DAY ONE...TODAY AND TONIGHT

THUNDERSTORMS...
SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP LATE THIS
AFTERNOON ACROSS CENTRAL SOUTH DAKOTA AND THEN SPREAD SOUTHEAST
ACROSS THE AREA DURING THE NIGHT. THE STORMS THAT DEVELOP WEST OF
INTERSTATE 29 WILL HAVE THE POTENTIAL TO PRODUCE LARGE HAIL TO
GOLF BALL SIZE AND DAMAGING WINDS TO AROUND 65 MPH...WITH AN
ISOLATED TORNADO POSSIBLE MAINLY THROUGH THE MID JAMES VALLEY
AREAS THROUGH AROUND SUNSET. A FEW STORMS LATE AFTERNOON INTO
EARLY EVENING COULD BE VERY SLOW MOVING...AND CAPABLE OF VERY
LARGE HAIL TO TENNIS BALL SIZE...AS WELL AS LOCALLY VERY HEAVY
RAINFALL. DAMAGING WINDS WILL BE THE MAIN THREAT EAST OF
INTERSTATE 29 LATER TONIGHT.

FLOODING...
THE JAMES RIVER WILL REMAIN IN FLOOD FOR THE FORESEEABLE
FUTURE...AND THE BIG SIOUX RIVER AT BRUCE WILL ALSO BE IN FLOOD
THROUGH AT LEAST THE BEGINNING OF NEXT WEEK.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

THE THREAT OF THUNDERSTORMS WILL PERSIST ACROSS THE AREA SUNDAY
MORNING...WITH ADDITIONAL REDEVELOPMENT EAST OF INTERSTATE 29
SUNDAY AFTERNOON. SOME OF THESE STORMS COULD BECOME SEVERE ACROSS
NORTHWEST IOWA BY EARLY AFTERNOON.

THERE WILL BE ANOTHER THREAT FOR THUNDERSTORMS ON WEDNESDAY INTO
WEDNESDAY NIGHT. SOME OF THESE STORMS MAY BE SEVERE.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL BE POSSIBLE AFTER 5 PM CDT IN LOWER BRULE
AREAS...AFTER 7 PM IN THE JAMES VALLEY...AND BY LATE EVENING
THROUGH THE INTERSTATE 29 CORRIDOR AND EASTWARD.

&&

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

In the hours before

Local storm report, Jul 10, 5:20 PM CDT, 2 hours 28 minutes before
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Local storm report, Jul 10, 5:28 PM CDT, 2 hours 20 minutes before
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Local storm report, Jul 10, 7:18 PM CDT, 30 minutes before
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      <div class="status" id="status">Temporary Notice</div>
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Local storm report, Jul 10, 7:33 PM CDT, 15 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
733 PM CDT SAT JUL 10 2010

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0715 PM     HAIL             4 S WHITE LAKE          43.68N 98.71W
07/10/2010  E1.50 INCH       AURORA             SD   PUBLIC

&&

JCHAPMAN
Local storm report, Jul 10, 7:35 PM CDT, 13 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
735 PM CDT SAT JUL 10 2010

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0645 PM     HAIL             2 W WHITE LAKE          43.73N 98.75W
07/10/2010  E0.88 INCH       AURORA             SD   PUBLIC

&&

JCHAPMAN
Local storm report, Jul 10, 7:42 PM CDT, 6 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
742 PM CDT SAT JUL 10 2010

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0712 PM     HAIL             WHITE LAKE              43.73N 98.71W
07/10/2010  M2.00 INCH       AURORA             SD   CO-OP OBSERVER

0714 PM     HAIL             3 S WHITE LAKE          43.69N 98.71W
07/10/2010  M1.75 INCH       AURORA             SD   CO-OP OBSERVER

&&

JCHAPMAN

The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 10, 7:08 PM CDTSevere Thunderstorm WarningFSDAurora37 min
Jul 10, 7:34 PM CDTSevere Thunderstorm WarningFSDAurora, Davison41 min
Jul 10, 7:59 PM CDTSevere Thunderstorm WarningFSDCharles Mix, Douglas46 min
Jul 10, 8:11 PM CDTSevere Thunderstorm WarningFSDDavison, Hanson49 min
Jul 10, 8:15 PM CDTSevere Thunderstorm WarningFSDBrookings, Kingsbury45 min
Jul 10, 8:20 PM CDTSevere Thunderstorm WarningFSDHanson, McCook40 min
Jul 10, 8:35 PM CDTSevere Thunderstorm WarningFSDLake40 min
Jul 10, 8:51 PM CDTSevere Thunderstorm WarningFSDBrookings39 min
Jul 10, 9:13 PM CDTFlash Flood WarningFSDAurora, Brule, Charles Mix, Davison, Douglas65 min
Jul 10, 10:27 PM CDTSevere Thunderstorm WarningFSDHutchinson, Turner, Yankton33 min
Jul 10, 9:29 PM CDTSevere Thunderstorm WarningFSDLincoln, Lyon46 min

Nearby

Flash Flood Warnings in South Dakota, 2010Every flash flood warning in 2010

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.