Alert archive / Iowa / Tornado Warnings in 2000

Tornado Warning 34, NWS Sioux Falls, SD

July 25, 2000Lyon County, Sioux County, Iowa

NWS Sioux Falls, SD issued this tornado warning at Jul 25, 2000, 10:17 PM CDT for Lyon County, Sioux County, Iowa. It was in force for 43 min. 1 report 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: Jul 25, 2000, 10:17 PM CDT (03:17 UTC)
Expired: Jul 25, 2000, 11:00 PM CDT
In force: 43 min
Issued by: NWS Sioux Falls, SD
Area: Whole counties

Counties Lyon County, IA, Sioux County, IA

The radar

The Sioux Falls radar (KFSD), 59 km from the middle of the area, began a volume at 03:21 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
Jul 25, 10:30 PM CDT	Hail 1.75	Rock Vly, IA	Large hail caused crop damage and damage to vehicles and windows, but the amount of damage was not determined.

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
Jul 25, 8:30 PM CDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 3.3 hours before the alert went out and 213 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: 2265 J/kg
Mixed-layer CIN: -76 J/kg
Mixed-layer LCL: 1234 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 22 m²/s²
0-3 km storm-relative helicity: 29 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 2.2

Open this sounding in Storm Lab

The text

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

000 
WFUS53 KFSD 260320
TORFSD

IAC119-167-260400-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1017 PM CDT TUE JUL 25 2000

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTHWEST LYON COUNTY IN NORTHWEST IOWA
  SIOUX COUNTY IN NORTHWEST IOWA

* UNTIL 1100 PM CDT

* AT 1017 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  TORNADO 4 MILES SOUTHWEST OF ALVORD...OR ABOUT 12 MILES EAST OF
  CANTON...MOVING SOUTHEAST AT 15 MPH.

* THE TORNADO WILL BE NEAR...
  DOON AROUND 1030 PM CDT
  ROCK VALLEY AROUND 1035 PM CDT
  HULL AROUND 1055 PM CDT

THIS WARNING REPLACES THE SEVERE THUNDERSTORM WARNING PREVIOUSLY
ISSUED FOR THE WARNED AREA.

THIS IS AN EXTREMELY DANGEROUS AND POTENTIALLY LIFE THREATENING
SITUATION. IF YOU ARE IN THE PATH OF THIS TORNADO...TAKE COVER
IMMEDIATELY. GO TO THE BASEMENT. IF A BASEMENT IS NOT AVAILABLE...GO
TO XA SMALL INTERIOR ROOM ON THE LOWEST FLOOR.

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 25, 8:39 PM CDT	Tornado Warning	FSD	Osceola	51 min
Jul 25, 9:41 PM CDT	Severe Thunderstorm Warning	FSD	Dickinson, Lyon, Osceola	49 min
Jul 25, 10:03 PM CDT	Severe Thunderstorm Warning	FSD	O'Brien, Sioux	42 min
Jul 25, 10:10 PM CDT	Tornado Warning	FSD	Dickinson	35 min
Jul 25, 10:28 PM CDT	Tornado Warning	FSD	Clay	47 min
Jul 25, 10:35 PM CDT	Severe Thunderstorm Warning	FSD	Osceola	25 min
Jul 25, 10:51 PM CDT	Severe Thunderstorm Warning	FSD	O'Brien	24 min
Jul 25, 10:59 PM CDT	Severe Thunderstorm Warning	FSD	Sioux	31 min
Jul 25, 11:18 PM CDT	Severe Thunderstorm Warning	FSD	O'Brien	27 min
Jul 25, 11:19 PM CDT	Severe Thunderstorm Warning	FSD	Buena Vista, Clay	26 min
Jul 25, 11:32 PM CDT	Severe Thunderstorm Warning	FSD	Cherokee	28 min
Jul 25, 11:47 PM CDT	Severe Thunderstorm Warning	FSD	Buena Vista	43 min
Jul 25, 11:59 PM CDT	Severe Thunderstorm Warning	FSD	Cherokee	31 min
Jul 26, 12:28 AM CDT	Severe Thunderstorm Warning	FSD	Buena Vista	32 min
Jul 26, 1:53 AM CDT	Severe Thunderstorm Warning	FSD	Clay	22 min

Nearby

Tornado Warnings in Iowa, 2000 Every tornado warning in 2000 Tornadoes in 2000

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.