Alert archive / Iowa / Severe Thunderstorm Warnings in 2008

Severe Thunderstorm Warning 28, NWS Sioux Falls, SD

May 6, 20084 counties in Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at May 6, 2008, 4:12 PM CDT for 4 counties in Iowa. It was in force for 48 min. 8 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: May 6, 2008, 4:12 PM CDT (21:12 UTC)
Expired: May 6, 2008, 5:00 PM CDT
In force: 48 min
Issued by: NWS Sioux Falls, SD
Area: Storm-based polygon

Counties Cherokee County, IA, O'Brien County, IA, Plymouth County, IA, Sioux County, IA

The radar

The Sioux Falls radar (KFSD), 114 km from the middle of the area, began a volume at 21:15 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.

What was reported inside it

Time	Report	Where	Remark
May 6, 4:15 PM CDT	TSTM WND DMG	Hospers, IA	6 INCH DIAMETER TREE BRANCHES BROKEN DOWN BY 60 TO 65 MPH WIND GUSTS.
May 6, 4:17 PM CDT	HAIL 0.88	Remsen, IA
May 6, 4:18 PM CDT	TSTM WND GST 60	3 E Hospers, IA	60 MPH WINDS BROKE DOWN 2 INCH DIAMETER BRANCHES.
May 6, 4:25 PM CDT	HAIL 0.88	Marcus, IA	IN ADDITION TO NICKEL SIZED HAIL, HEAVY RAIN WAS FALLING.
May 6, 4:33 PM CDT	TSTM WND GST 60	Cleghorn, IA
May 6, 4:35 PM CDT	HAIL 0.75	Cleghorn, IA
May 6, 4:45 PM CDT	HAIL 0.75	Cherokee, IA	PENNY SIZED HAIL COVERING THE GROUND.
May 6, 4:50 PM CDT	HAIL 0.88	Meriden, IA	IN ADDITION TO NICKEL SIZED HAIL, WINDS WERE GUSTING TO AROUND 25 MPH.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

Did it verify

Verified. The Iowa Environmental Mesonet's Cow matched 3 storm reports to this severe thunderstorm warning; the first came 3 minutes after it went out.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
May 6, 12:03 PM CDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 9.2 hours before the alert went out and 188 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 60 J/kg
Mixed-layer CIN: -206 J/kg
Mixed-layer LCL: 1232 m above ground
0-6 km bulk shear: 38 kt
0-1 km storm-relative helicity: -37 m²/s²
0-3 km storm-relative helicity: -3 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WUUS53 KFSD 062112
SVRFSD
IAC035-141-149-167-062200-
/O.NEW.KFSD.SV.W.0028.080506T2112Z-080506T2200Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
412 PM CDT TUE MAY 6 2008

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHERN CHEROKEE COUNTY IN NORTHWEST IOWA
  OBRIEN COUNTY IN NORTHWEST IOWA
  EASTERN PLYMOUTH COUNTY IN NORTHWEST IOWA
  EASTERN SIOUX COUNTY IN NORTHWEST IOWA

* UNTIL 500 PM CDT

* AT 412 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING NICKEL SIZE
  HAIL...AND DESTRUCTIVE WINDS IN EXCESS OF 70 MPH.  THESE STORMS
  WERE LOCATED ALONG A LINE EXTENDING FROM 5 MILES WEST OF SHELDON TO
  GRANVILLE TO 5 MILES SOUTHWEST OF REMSEN...OR ALONG A LINE
  EXTENDING FROM 13 MILES NORTHEAST OF ORANGE CITY TO 12 MILES EAST
  OF ORANGE CITY TO 7 MILES EAST OF LE MARS...MOVING EAST AT 43 MPH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  PAULLINA...ARCHER AROUND 420 PM CDT...
  MARCUS AROUND 425 PM CDT...
  SANBORN...PRIMGHAR...CLEGHORN AROUND 430 PM CDT...
  SUTHERLAND AROUND 435 PM CDT...
  LARRABEE AROUND 440 PM CDT...
  HARTLEY...CHEROKEE AROUND 445 PM CDT...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 700 PM CDT
TUESDAY EVENING FOR NORTHWEST IOWA AND SOUTHWEST MINNESOTA AND
NORTHEAST NEBRASKA AND SOUTHEASTERN SOUTH DAKOTA.

LAT...LON 4273 9541 4275 9609 4295 9589 4316 9600
      4325 9540 4292 9541
TIME...MOT...LOC 2112Z 264DEG 37KT 4317 9592 4296 9582
          4276 9603

$$

08

2 follow-up statements

000 
WWUS53 KFSD 062130
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
429 PM CDT TUE MAY 6 2008

IAC035-141-149-167-062200-
/O.CON.KFSD.SV.W.0028.000000T0000Z-080506T2200Z/
SIOUX IA-OBRIEN IA-CHEROKEE IA-PLYMOUTH IA-
429 PM CDT TUE MAY 6 2008

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 500 PM CDT
FOR NORTHEASTERN PLYMOUTH...NORTHERN CHEROKEE...OBRIEN AND
SOUTHEASTERN SIOUX COUNTIES...

AT 429 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING NICKEL
SIZE HAIL...AND DESTRUCTIVE WINDS IN EXCESS OF 70 MPH.  THESE STORMS
WERE LOCATED ALONG A LINE EXTENDING FROM 5 MILES NORTH OF ARCHER TO
PAULLINA TO 5 MILES SOUTHWEST OF MARCUS...OR ALONG A LINE EXTENDING
FROM 20 MILES NORTHEAST OF ORANGE CITY TO 21 MILES EAST OF ORANGE
CITY TO 16 MILES EAST OF LE MARS...MOVING EAST AT 43 MPH.

SEVERE THUNDERSTORMS WILL BE NEAR...
   SUTHERLAND...CALUMET AROUND 435 PM CDT...
   MERIDEN...LARRABEE AROUND 440 PM CDT...
   HARTLEY...CHEROKEE AROUND 445 PM CDT...

AT 425 PM CDT...NICKEL SIZED HAIL WAS REPORTED AT MARCUS.

AT 418 PM CDT...60 MPH WINDS WITH BRANCHED DOWN WERE REPORTED 7 
MILES SOUTH OF SHELDON.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 700 PM CDT
TUESDAY EVENING FOR NORTHWEST IOWA AND SOUTHWEST MINNESOTA AND
NORTHEAST NEBRASKA AND SOUTHEASTERN SOUTH DAKOTA.

LAT...LON 4273 9541 4275 9609 4295 9589 4316 9600
      4325 9540 4292 9541
TIME...MOT...LOC 2129Z 264DEG 37KT 4319 9568 4297 9558
          4278 9579

$$

08

000 
WWUS53 KFSD 062157
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
457 PM CDT TUE MAY 6 2008

IAC035-141-149-167-062207-
/O.EXP.KFSD.SV.W.0028.000000T0000Z-080506T2200Z/
SIOUX IA-OBRIEN IA-CHEROKEE IA-PLYMOUTH IA-
457 PM CDT TUE MAY 6 2008

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN PLYMOUTH...
NORTHERN CHEROKEE...OBRIEN AND SOUTHEASTERN SIOUX COUNTIES WILL
EXPIRE AT 500 PM CDT...

THE STORM HAS EXITED THE WARNED AREA.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 700 PM CDT
TUESDAY EVENING FOR NORTHWEST IOWA AND SOUTHWEST MINNESOTA AND
NORTHEAST NEBRASKA AND SOUTHEASTERN SOUTH DAKOTA.

LAT...LON 4273 9541 4275 9609 4295 9589 4316 9600
      4325 9540 4292 9541
TIME...MOT...LOC 2157Z 264DEG 37KT 4322 9529 4300 9519
          4281 9540

$$

08

What forecasters said that day

The local office's own words before this severe thunderstorm 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 severe thunderstorm warning went out at May 6, 3:30 PM CDT, 42 minutes earlier.

Area forecast discussion, May 6, 3:30 PM CDT, 42 minutes before

AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NATIONAL WEATHER SERVICE SIOUX FALLS SD
330 PM CDT TUE MAY 6 2008

.DISCUSSION...

HAIL AND HIGH WIND BOW ECHO COMPLEX EXPCD TO MOVE EWD FM FAR SERN SD
THRU NWRN IA THRU EARLY TNGT...WITH SCT SHRA/TSRA ELSEWHERE. SOME
REDEVELOPMENT STILL EXPCD AHEAD OF CDFNT MOVG FM CNTRL SD THRU
EVE...BUT RESPONSIBLE SHORT WAVE SHOULD PUSH MOST EVERYTHING EAST OF
AREA BY MIDN. CDFNT MOVG SEWD OVR CWA DURG NGT WILL BE FLWD BY NWLY
FLOW OF COOLER AIR AND ASSCD SC DECK...BUT AIR MASS BECOMES RATHER
DRY TO THE NORTH. SC DECK SHOULD AFFECT MAINLY NRN TO ERN CWA...BUT
SHOULD NOT BE TOO WDSPRD OR SOLID.

WITH PCPN OUT FOR WED WE SHUD FACE A DRY DAY WITH PTCLDY SKIES AND
TEMPS WHICH ARE SEASONBLY COOL...BREEZY CONDS ADDING TO THE COOL
FEELING ESPLY E...BUT STILL NOT BAD GIVEN SOME REALLY COOL TEMPS
THIS SPRING. WE THEN AWAIT THE NEXT SYS MOVG IN FROM THE W LATE WED
NGT AND THU. ADVANCE OF THIS SYS OVER AREA WILL APPARNTLY BE FAIRLY
SLOW AFTER MORE RPD DVLPMNT OVER THE FAR WRN PART OF FCST AREA. THRU
THU BEST RAIN POTENTL WILL BE OUT W...MOVG ITO THE E THU NGT. ECMFW
AGN THE MOST BULLISH ON THIS SYS BUT GFS AND NAM NOT BAD. AM HOLDING
OUT ON POPS A LTL DUE TO TIMING ISSUES BUT SUSPECT BY ERY MRNG FCST
WE WILL BE ABLE TO GO WITH SOME LIKELIES...AT LEAST. HALF DECENT
UPPER SUPPORT WILL COMBINE WITH EXCELLENT THERMAL LIFT POTENTL. ENUF
MOISTR SHUD BE AVBL FOR DECENT RAIN...THO PCPN CVRG CUD BE LINKED TO
DVLPMNT OF CONVECTN IN THE MORE UNSTBL AIR TO THE S OF AREA.
STILL...I BE CAREFUL ABOUT PLANNING ANY PICNICS FOR THU OVER FCST
AREA ESPLY OUT W.

FRI SHUD BE ANOTHER BREAK DAY BEFORE A SYS ARRIVES FOR SAT. STILL
ANOTHER DRY DAY MOST OF AREA SUN THEN ANOTHER SYS MAY AFFECT THE
AREA MON/TUE...WHICH ECMWF MAKES QUITE STG. UNCERTAINTY WITH
TIMING...STRNGTH...AND TEMPS GROW GREATER WITH EACH SYS. GFS MAKES
THINGS QUITE COOL LATE IN FCST PD...COOLR THAN THE UPPER 50S TO MID
60S I AM GOING WITH. OF COURSE ECMWF WITH ITS STRONG SYS LATE IN PD
WARMS IT UP WELL AHD OF SYS. HPC GUIDNCE LOOKS LIKE GOOD COMPROMISE
FOR NOW.

&&

.AVIATION...
MOSTLY VFR...BUT MVFR CONDITIONS IN SCT STRONGER TSTMS MOVG EWD
MAINLY SERN CWA THRU EARLY TNGT. MORE MVFR CIGS PSBL WITH SC MOVG
SEWD OVR CWA FM 07Z TO 16Z IN NWLY FLOW BEHIND CDFNT.

&&

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

&&

RYRHOLM/WILLIAMS

Hazardous weather outlook, May 6, 11:33 AM CDT, 4 hours 39 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1133 AM CDT TUE MAY 06 2008

SDZ038>040-050-052>071-MNZ071-072-080-081-089-090-097-098-
IAZ001>003-012>014-020>022-031-032-NEZ013-014-071200-
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-
1133 AM CDT TUE MAY 06 2008

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

.DAY ONE...TODAY AND TONIGHT

THUNDERSTORMS...
THUNDERSTORMS WILL CONTINUE TO DEVELOP NORTH OF INTERSTATE 90
THIS AFTERNOON...WITH HAIL UP TO NICKEL SIZE POSSIBLE. IN THE
MEANTIME...A STRONGER COMPLEX OF THUNDERSTORMS IN SOUTH CENTRAL
SOUTH DAKOTA AROUND NOONTIME WILL MOVE EASTWARD TO THE SOUTH OF
INTERSTATE 90 OVER SOUTHEAST SOUTH DAKOTA...FAR NORTHEAST
NEBRASKA...AND INTO NORTHWEST IOWA LATER THIS AFTERNOON THROUGH
EARLY TONIGHT. LARGE HAIL TO THE SIZE OF GOLF BALLS AND WIND
GUSTS AROUND 60 MPH WILL BE POSSIBLE WITH SOME OF THESE STORMS.
THE STRONGEST STORMS SHOULD BE NEAR THE MISSOURI RIVER VALLEY.

FLOODING...
MINOR FLOODING WILL CONTINUE ON THE LITTLE SIOUX RIVER FROM NORTH
OF SPENCER TO NEAR LINN GROVE IN NORTHWEST IOWA. THE RIVER SHOULD
FALL BELOW FLOOD STAGE BY WEDNESDAY...UNLESS SIGNIFICANT RAIN
FALLS TUESDAY OR TUESDAY NIGHT.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL BE LIKELY BY NOON TIME IN SOUTH CENTRAL
SOUTH DAKOTA...BY 3 PM WEST OF INTERSTATE 29...AND BY 5 PM EAST
OF INTERSTATE 29.

&&

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

RSR

In the hours before

Local storm report, May 6, 3:28 PM CDT, 44 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
328 PM CDT TUE MAY 06 2008

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

0318 PM     HAIL             VERMILLION              42.78N 96.93W
05/06/2008  E0.75 INCH       CLAY               SD   TRAINED SPOTTER

            IN ADDITION TO PENNY SIZED HAIL, THERE WERE WIND GUSTS TO
            AROUND 40 MPH AND HEAVY RAIN.

&&

TRM

Local storm report, May 6, 3:35 PM CDT, 37 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
335 PM CDT TUE MAY 06 2008

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

0315 PM     TSTM WND GST     8 S BERESFORD           42.96N 96.79W
05/06/2008  E60 MPH          UNION              SD   PUBLIC

            60 MPH WIND GUSTS BROKE TREE BRANCHES DOWN AND BLEW STUFF
            AROUND ON THE WEST SIDE OF THE HOUSE.

&&

TRM

Local storm report, May 6, 3:42 PM CDT, 30 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
342 PM CDT TUE MAY 06 2008

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

0337 PM     HAIL             HAWARDEN                43.00N 96.48W
05/06/2008  E1.00 INCH       SIOUX              IA   EMERGENCY MNGR

&&

TRM

Local storm report, May 6, 3:43 PM CDT, 29 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
343 PM CDT TUE MAY 06 2008

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

0337 PM     TSTM WND GST     HAWARDEN                43.00N 96.48W
05/06/2008  E60 MPH          SIOUX              IA   EMERGENCY MNGR

&&

TRM

Local storm report, May 6, 3:50 PM CDT, 22 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
350 PM CDT TUE MAY 06 2008

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

0340 PM     HAIL             4 SSW CRAIG             42.84N 96.35W
05/06/2008  E0.75 INCH       PLYMOUTH           IA   TRAINED SPOTTER

&&

TRM

Local storm report, May 6, 4:09 PM CDT, 3 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
409 PM CDT TUE MAY 06 2008

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

0357 PM     TSTM WND GST     3 NNW LE MARS           42.83N 96.20W
05/06/2008  M64 MPH          PLYMOUTH           IA   TRAINED SPOTTER

&&

TRM

The office that day

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

Issued	Product	Office	Counties	Lasted
May 6, 3:28 PM CDT	Severe Thunderstorm Warning	FSD	Plymouth, Sioux	47 min
May 6, 4:21 PM CDT	Severe Thunderstorm Warning	FSD	Plymouth, Woodbury	39 min
May 6, 4:37 PM CDT	Severe Thunderstorm Warning	FSD	Buena Vista, Clay	53 min
May 6, 4:46 PM CDT	Severe Thunderstorm Warning	FSD	Cherokee, Plymouth, Woodbury	44 min
May 6, 4:54 PM CDT	Severe Thunderstorm Warning	FSD	Sioux	36 min
May 6, 4:56 PM CDT	Severe Thunderstorm Warning	FSD	Buena Vista	34 min
May 6, 5:28 PM CDT	Severe Thunderstorm Warning	FSD	Ida, Woodbury	47 min
May 6, 6:12 PM CDT	Severe Thunderstorm Warning	FSD	Ida, Woodbury	33 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2008 Every severe thunderstorm warning in 2008

Sources

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