Alert archive / Iowa / Tornado Warnings in 2001

Tornado Warning 72, NWS Omaha, NE

August 17, 2001Monona County, Iowa

NWS Omaha, NE issued this tornado warning at Aug 17, 2001, 7:51 PM CDT for Monona County, Iowa. It was in force for 24 min. 1 report came from inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties, with what was reported inside it.

The facts

Issued: Aug 17, 2001, 7:51 PM CDT (00:51 UTC)
Expired: Aug 17, 2001, 8:15 PM CDT
In force: 24 min
Issued by: NWS Omaha, NE
Area: Whole counties; the outline is the Mesonet’s reconstruction

County Monona County, IA

What was reported inside it

Time	Report	Where	Remark
Aug 17, 7:58 PM CDT	Hail 1.5	Turin, 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
Aug 17, 5:30 PM CDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 0.9 hours before the alert went out and 104 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: 2452 J/kg
Mixed-layer CIN: -1 J/kg
Mixed-layer LCL: 1134 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: 66 m²/s²
0-3 km storm-relative helicity: 166 m²/s²
Significant tornado parameter: 0.7
Supercell composite: 3.9

Open this sounding in Storm Lab

The text

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

510 
WFUS53 KOAX 180052
TOROMA
IAC133-180115-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE OMAHA NE
751 PM CDT FRI AUG 17 2001

THE NATIONAL WEATHER SERVICE IN OMAHA HAS ISSUED A

* TORNADO WARNING FOR...
  MONONA COUNTY IN WEST CENTRAL IOWA

* UNTIL 815 PM CDT

* AT 749 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  TORNADO 2 MILES SOUTHEAST OF CASTANA...OR ABOUT 40 MILES SOUTHEAST
  OF SIOUX CITY...MOVING SOUTHEAST AT 15 MPH.

* THE TORNADO IS EXPECTED TO BE NEAR...
RURAL EASTERN MONONA COUNTY AROUND 800 PM CDT

TAKE COVER NOW IN A BASEMENT OR IN AN INTERIOR ROOM ON THE LOWEST
LEVEL OF A STRONG BUILDING. CARS AND MOBILE HOMES SHOULD BE
ABANDONED. GO TO A SAFE PLACE NOW.

LAT...LON 4220 9603 4193 9588 4217 9551 4233 9572

POLLACK

The office that day

Everything else NWS Omaha, NE issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 17, 7:14 PM CDT	Severe Thunderstorm Warning	OAX	Monona	31 min
Aug 17, 7:47 PM CDT	Severe Thunderstorm Warning	OAX	Monona	28 min
Aug 17, 8:14 PM CDT	Severe Thunderstorm Warning	OAX	Shelby	31 min
Aug 17, 8:14 PM CDT	Tornado Warning	OAX	Harrison, Monona	31 min
Aug 17, 8:23 PM CDT	Tornado Warning	OAX	Shelby	37 min
Aug 17, 8:45 PM CDT	Severe Thunderstorm Warning	OAX	Harrison	45 min
Aug 17, 9:00 PM CDT	Severe Thunderstorm Warning	OAX	Shelby	30 min
Aug 17, 10:07 PM CDT	Severe Thunderstorm Warning	OAX	Pottawattamie	23 min
Aug 17, 10:27 PM CDT	Severe Thunderstorm Warning	OAX	Montgomery	48 min
Aug 17, 11:00 PM CDT	Severe Thunderstorm Warning	OAX	Mills	30 min
Aug 17, 11:14 PM CDT	Severe Thunderstorm Warning	OAX	Page	46 min

Nearby

Tornado Warnings in Iowa, 2001 Every tornado warning in 2001 Tornadoes in 2001

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.