Alert archive / Iowa / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 306, NWS Sioux Falls, SD

August 16, 2002Lyon County, Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at Aug 16, 2002, 3:10 PM CDT for Lyon County, Iowa. It was in force for 35 min. 1 report 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: Aug 16, 2002, 3:10 PM CDT (20:10 UTC)
Expired: Aug 16, 2002, 3:45 PM CDT
In force: 35 min
Issued by: NWS Sioux Falls, SD
Area: Counties, with a storm outline in the text

County Lyon County, IA

The radar

The Sioux Falls radar (KFSD), 43 km from the middle of the area, began a volume at 20:12 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
Aug 16, 3:19 PM CDT	Hail 1.75	Lester, IA	Large hail damaged vehicles. The amount of damage was not known.

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
Aug 16, 11:55 AM CDT	Severe Thunderstorm Watch	SPC	4 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 8.2 hours before the alert went out and 235 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: 2380 m above ground
0-6 km bulk shear: 41 kt
0-1 km storm-relative helicity: -16 m²/s²
0-3 km storm-relative helicity: 189 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.

273 
WUUS53 KFSD 162010
SVRFSD
IAC119-162045-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
310 PM CDT FRI AUG 16 2002

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  LYON COUNTY IN NORTHWEST IOWA

* UNTIL 345 PM CDT

* AT 310 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 3 MILES SOUTH OF LARCHWOOD...OR ABOUT 11 MILES
  NORTHEAST OF CANTON...MOVING EAST AT 55 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  ROCK RAPIDS AROUND 320 PM CDT
  LITTLE ROCK AROUND 335 PM CDT

THIS STORM WILL PRODUCE LARGE HAIL. GO INSIDE A STURDY BUILDING AND
STAY AWAY FROM WINDOWS.

LAT...LON 4349 9650 4331 9645 4335 9587 4350 9588

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 16, 1:08 PM CDT	Severe Thunderstorm Warning	FSD	Woodbury	37 min
Aug 16, 1:19 PM CDT	Severe Thunderstorm Warning	FSD	Plymouth	41 min
Aug 16, 1:44 PM CDT	Severe Thunderstorm Warning	FSD	Ida, Woodbury	31 min
Aug 16, 2:01 PM CDT	Severe Thunderstorm Warning	FSD	Plymouth, Sioux	29 min
Aug 16, 2:20 PM CDT	Severe Thunderstorm Warning	FSD	Ida, Woodbury	25 min
Aug 16, 2:30 PM CDT	Severe Thunderstorm Warning	FSD	Sioux	30 min
Aug 16, 3:23 PM CDT	Severe Thunderstorm Warning	FSD	Clay, O'Brien	52 min
Aug 16, 3:32 PM CDT	Severe Thunderstorm Warning	FSD	Cherokee	18 min
Aug 16, 3:56 PM CDT	Severe Thunderstorm Warning	FSD	Buena Vista	34 min
Aug 16, 4:16 PM CDT	Severe Thunderstorm Warning	FSD	Clay	29 min
Aug 16, 4:32 PM CDT	Severe Thunderstorm Warning	FSD	Osceola	28 min
Aug 16, 4:53 PM CDT	Severe Thunderstorm Warning	FSD	Dickinson	37 min
Aug 16, 6:04 PM CDT	Severe Thunderstorm Warning	FSD	Clay	26 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2002 Every severe thunderstorm warning in 2002

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; radar from the NEXRAD Level II archive.