Alert archive / Iowa / Tornado Warnings in 2001

Tornado Warning 5, NWS Quad Cities, IA

April 11, 2001Benton County, Iowa

NWS Quad Cities, IA issued this tornado warning at Apr 11, 2001, 4:42 PM CDT for Benton County, Iowa. It was in force for 18 min. No storm report in the archive falls 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.

The facts

Issued
Apr 11, 2001, 4:42 PM CDT (21:42 UTC)
Expired
Apr 11, 2001, 5:00 PM CDT
In force
18 min
Issued by
NWS Quad Cities, IA
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Benton County, IA

The watch it was issued in

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

IssuedProductOfficeLasted
Apr 11, 12:00 PM CDTTornado WatchSPC5 hr
Apr 11, 4:00 PM CDTTornado WatchSPC6 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 9.7 hours before the alert went out and 154 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-pSkew-T log-p diagram, Davenport, at 12:00Z on 2001-04-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 196 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 12:00Z on 2001-04-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 336 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
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
196 J/kg
Mixed-layer CIN
-182 J/kg
Mixed-layer LCL
822 m above ground
0-6 km bulk shear
63 kt
0-1 km storm-relative helicity
336 m²/s²
0-3 km storm-relative helicity
387 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.8

Open this sounding in Storm Lab

The text

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

000 
WFUS53 KDVN 112142
TORMLI
IAC011-112200-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
442 PM CDT WED APR 11 2001

THE NATIONAL WEATHER SERVICE IN QUAD CITIES HAS ISSUED A

* TORNADO WARNING FOR...
  WESTERN BENTON COUNTY IN EAST CENTRAL IOWA

* UNTIL 500 PM CDT

* AT 439 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM WITH A DEVELOPING TORNADO 15 MILES SOUTHWEST OF
  GARRISON...OR 8 MILES NORTHWEST OF BELLE PLAINE...MOVING NORTH AT
  55 MPH.

* THE TORNADO IS EXPECTED TO BE NEAR...
  7 MILES WEST OF GARRISON BY 455 PM CDT.
  8 MILES WEST OF MOUNT AUBURN BY 500 PM CDT.

THE SAFEST PLACE TO BE DURING A TORNADO IS IN A BASEMENT. SEEK
SHELTER ON THE LOWEST FLOOR OF THE BUILDING IN AN INTERIOR HALLWAY OR
ROOM SUCH AS A CLOSET. USE BLANKETS OR PILLOWS TO COVER YOUR BODY AND
ALWAYS STAY AWAY FROM WINDOWS.

LAT...LON 4196 9231 4197 9223 4229 9208 4228 9230

MCCLURE

The office that day

Everything else NWS Quad Cities, IA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 11, 4:17 PM CDTTornado WarningDVNKeokuk28 min
Apr 11, 4:38 PM CDTTornado WarningDVNWashington22 min
Apr 11, 4:51 PM CDTTornado WarningDVNIowa, Johnson24 min
Apr 11, 5:10 PM CDTTornado WarningDVNJohnson, Linn35 min
Apr 11, 5:15 PM CDTTornado WarningDVNBuchanan30 min
Apr 11, 5:43 PM CDTTornado WarningDVNLinn32 min

Nearby

Tornado Warnings in Iowa, 2001Every tornado warning in 2001Tornadoes 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; the sounding from the Mesonet's radiosonde archive.