Alert archive / Iowa / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 32, NWS Sioux Falls, SD

May 16, 1999Cherokee County, O'Brien County, Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at May 16, 1999, 5:45 PM CDT for Cherokee County, O'Brien County, Iowa. It was in force for 30 min. 2 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued: May 16, 1999, 5:45 PM CDT (22:45 UTC)
Expired: May 16, 1999, 6:15 PM CDT
In force: 30 min
Issued by: NWS Sioux Falls, SD
Area: Whole counties

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

What was reported inside it

Time	Report	Where	Remark
May 16, 5:50 PM CDT	Hail 0.88	Larrabee, IA
May 16, 6:00 PM CDT	Hail 1	Sutherland, IA

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

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 16, 3:00 PM CDT	Tornado Watch	SPC	6 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 10.8 hours before the alert went out and 270 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 597 m above ground
0-6 km bulk shear: 38 kt
0-1 km storm-relative helicity: 82 m²/s²
0-3 km storm-relative helicity: 142 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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 16, 3:15 PM CDT, 2 hours 30 minutes earlier.

Area forecast discussion, May 16, 3:15 PM CDT, 2 hours 30 minutes before

AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NATIONAL WEATHER SERVICE SIOUX FALLS SD
315 PM CDT SUN MAY 16 1999

PLENTY GOING ON IN THE SHORT TERM. SFC BNDRY HAS STRETCHED TO NR
KMWM TO ARND KSUX BY MID AFTN. 18Z GOES CAPES ARE AROUND 2000 J/KG
WITH LIS STILL ARND -6 IN THE KSUX AREA. THIS FACT COUPLED WITH
FUNNEL CLD REPORTS RECENTLY IN MURRAY CNTY MINNESOTA...WHERE SOME
DAYTIME HTG WAS REALIZED SHOW HOW UNSTABLE THINGS ARE. THESE ARE NOT
COLD AIR FUNNELS. SFC PLOTS SHOW QUITE A CYCLONIC SPIN OVR SERN QUAD
OF CWA. DECIDED TO GO AHD AND KEEP TOR WATCH IN FOR KSUX AREA ERLY
THIS EVENING UNTIL BNDRY PASSES FURTHER SOUTH.

OTHERWISE...AVN AND ETA SOLNS ARE ABOUT SIX HRS FASTER THAN THE
NGM...AND THESE SOLNS WERE FOLLOWED JUDGING FM CRNT MESOSCALE
FEATURES. HOWEVER...UNTIL FINAL UPPER AIR TROF MOVES THRU THE NRN
PLAINS TNGT...CWA RUNS THE RISK OF SHWRS AND TSTMS WITH INCREASING
CHCS HEADING EAST AND SOUTHEAST. REALLY RESEMBLES SOMEWHAT OF AN
OVERRUNING SITUATION TNGT WITH SWRLY FLOW ALOFT...AMPLE MSTR...
DIFFERENCE BEING PLENTY OF COLD AIR ALOFT.

SYSTEM BEGINS TO EJECT FAR ENUF EAST ON MONDAY TO DECR THE CLDS OVR
MUCH OF THE CWA...BUT STILL SOME SCT SHWRS MAY LINGER OVR ERN
SECTIONS IN THE MRNG. BY MON NIGHT AND TUESDAY...PARTLY CLDY SKIES
SHOULD RETURN. CNCRND ABOUT AREAS OF FOG MON NIGHT OVR ERN PTNS WITH
LIGHT WINDS AND RESIDUAL SFC MSTR. WNDS SHOULD REALLY INCR OVR THE
JAMES VALLEY IN THE SOUTH ON TUESDAY AS LOW PRES DVLPS OVR HIGH
PLAINS.

.FSD...NONE.
FUHS

In the hours before

Local storm report, May 16, 5:32 PM CDT, 13 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
532 PM CDT SUN MAY 16 1999

TIME(CDT)  .....CITY LOCATION..... STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0345 PM    3 SW CORRECTIONVILLE      IA    1 INCH HAIL
05/16/99   WOODBURY

0348 PM    DANBURY                   IA    .75 INCH HAIL
05/16/99   WOODBURY

0413 PM    WASHTA                    IA    1 INCH HAIL
05/16/99   CHEROKEE

0430 PM    CHEROKEE                  IA    1 INCH HAIL
05/16/99   CHEROKEE

0445 PM    2 S CALUMET               IA    1.75 INCH HAIL
05/16/99   CHEROKEE

Local storm report, May 16, 5:32 PM CDT, 13 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
532 PM CDT SUN MAY 16 1999

TIME(CDT)  .....CITY LOCATION..... STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0345 PM    3 SW CORRECTIONVILLE      IA    1 INCH HAIL
05/16/99   WOODBURY

0348 PM    DANBURY                   IA    .75 INCH HAIL
05/16/99   WOODBURY

0413 PM    WASHTA                    IA    1 INCH HAIL
05/16/99   CHEROKEE

0430 PM    CHEROKEE                  IA    1 INCH HAIL
05/16/99   CHEROKEE

0445 PM    2 S CALUMET               IA    1.75 INCH HAIL
05/16/99   CHEROKEE

The office that day

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

Issued	Product	Office	Counties	Lasted
May 16, 8:28 AM CDT	Severe Thunderstorm Warning	FSD	Clay, Yankton	32 min
May 16, 8:57 AM CDT	Severe Thunderstorm Warning	FSD	Clay, Union	33 min
May 16, 7:51 AM CDT	Severe Thunderstorm Warning	FSD	Ida, Woodbury	24 min
May 16, 9:20 AM CDT	Severe Thunderstorm Warning	FSD	Buena Vista, Ida	25 min
May 16, 3:24 PM CDT	Severe Thunderstorm Warning	FSD	Ida, Woodbury	36 min
May 16, 3:49 PM CDT	Severe Thunderstorm Warning	FSD	Cherokee	26 min
May 16, 4:00 PM CDT	Severe Thunderstorm Warning	FSD	Ida, Woodbury	30 min
May 16, 4:16 PM CDT	Severe Thunderstorm Warning	FSD	Buena Vista, Cherokee	29 min
May 16, 4:20 PM CDT	Tornado Warning	FSD	Ida	30 min
May 16, 4:55 PM CDT	Severe Thunderstorm Warning	FSD	Dickinson	35 min
May 16, 5:05 PM CDT	Severe Thunderstorm Warning	FSD	Cherokee, Woodbury	30 min
May 16, 5:41 PM CDT	Severe Thunderstorm Warning	FSD	Dickinson, Osceola	34 min

Nearby

Severe Thunderstorm Warnings in Iowa, 1999 Every severe thunderstorm warning in 1999

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.