Alert archive / Iowa / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 59, NWS Des Moines, IA

April 11, 2001Bremer County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Apr 11, 2001, 5:01 PM CDT for Bremer County, Iowa. It was in force for 39 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, 5:01 PM CDT (22:01 UTC)
Expired: Apr 11, 2001, 5:40 PM CDT
In force: 39 min
Issued by: NWS Des Moines, IA
Area: Whole counties; the outline is the Mesonet’s reconstruction

County Bremer County, IA

The radar

The La Crosse radar (KARX), 148 km from the middle of the area, began a volume at 22:01 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.

The watch it was issued in

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

Issued	Product	Office	Lasted
Apr 11, 4:00 PM CDT	Tornado Watch	SPC	6 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 10.0 hours before the alert went out and 203 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: 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 
WUUS53 KDMX 112202
SVRDSM
IAC017-112240-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
501 PM CDT WED APR 11 2001

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  BREMER COUNTY IN NORTHEAST IOWA

* UNTIL 540 PM CDT

* AT 459 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 7 MILES SOUTH OF WAVERLY...OR ABOUT 11 MILES
  NORTHWEST OF WATERLOO...MOVING NORTHEAST AT 60 MPH.

* THE SEVERE THUNDERSTORM WILL BE...
  NEAR TRIPOLI AND WAVERLY AROUND 510 PM

HAIL UP TO THE SIZE OF NICKELS AND VERY STRONG WINDS ARE LIKELY IN 
THE WARNED AREA.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 1000 PM WEDNESDAY EVENING FOR
EASTERN IOWA.

LAT...LON 4292 9256 4265 9255 4265 9210 4291 9209

COGIL

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 Des Moines, IA wrote its last area forecast discussion before this severe thunderstorm warning went out at Apr 11, 2:50 PM CDT, 2 hours 11 minutes earlier.

Area forecast discussion, Apr 11, 2:50 PM CDT, 2 hours 11 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
250 PM CDT WED APR 11 2001

SVR WX WITH NO SIG TIME.  LAST LN ABT TO MOV THRU DSM ATTM AND WL
LFT NE OF CWA THIS EVE.  STG SLY WINDS BCMG W-NW POST DRY SLOT.  WL
GO WND ADVY TNGT THRU THU, THO CUD SEE WNDS DMSH THU AFTN.  NXT WK
SYS FRI NGT, AFT THAT A SAT NGT INTO SUN WK EVENT.  OPTED WITH MAV
GUID.
DSM 22-13   ALO 63-14

.DSM...WND ADVY ALL ZONES TNGT AND THU
MS APR 01

The office that day

Everything else NWS Des Moines, IA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 11, 4:12 AM CDT	Severe Thunderstorm Warning	DMX	Adams, Cass, Taylor	38 min
Apr 11, 11:32 AM CDT	Tornado Warning	DMX	Ringgold	33 min
Apr 11, 12:00 PM CDT	Tornado Warning	DMX	Ringgold, Union	40 min
Apr 11, 12:19 PM CDT	Tornado Warning	DMX	Clarke	31 min
Apr 11, 12:29 PM CDT	Tornado Warning	DMX	Madison	46 min
Apr 11, 12:39 PM CDT	Tornado Warning	DMX	Dallas, Polk, Warren	51 min
Apr 11, 1:28 PM CDT	Tornado Warning	DMX	Polk	2 min
Apr 11, 1:46 PM CDT	Severe Thunderstorm Warning	DMX	Union	29 min
Apr 11, 1:50 PM CDT	Severe Thunderstorm Warning	DMX	Adair	40 min
Apr 11, 1:55 PM CDT	Severe Thunderstorm Warning	DMX	Crawford	35 min
Apr 11, 1:59 PM CDT	Tornado Warning	DMX	Audubon	31 min
Apr 11, 2:32 PM CDT	Tornado Warning	DMX	Greene, Guthrie	28 min
Apr 11, 2:36 PM CDT	Severe Thunderstorm Warning	DMX	Dallas	29 min
Apr 11, 2:48 PM CDT	Severe Thunderstorm Warning	DMX	Boone, Polk	42 min
Apr 11, 2:58 PM CDT	Tornado Warning	DMX	Boone	32 min
Apr 11, 3:02 PM CDT	Tornado Warning	DMX	Calhoun, Greene, Webster	43 min
Apr 11, 3:02 PM CDT	Tornado Warning	DMX	Lucas, Marion	28 min
Apr 11, 3:18 PM CDT	Tornado Warning	DMX	Hamilton	32 min
Apr 11, 3:43 PM CDT	Tornado Warning	DMX	Jasper, Marshall	32 min
Apr 11, 3:45 PM CDT	Tornado Warning	DMX	Wright	45 min
Apr 11, 3:51 PM CDT	Tornado Warning	DMX	Franklin, Hamilton, Hardin	44 min
Apr 11, 4:02 PM CDT	Severe Thunderstorm Warning	DMX	Poweshiek	28 min
Apr 11, 4:05 PM CDT	Tornado Warning	DMX	Wapello	20 min
Apr 11, 4:23 PM CDT	Severe Thunderstorm Warning	DMX	Cerro Gordo	32 min
Apr 11, 4:27 PM CDT	Severe Thunderstorm Warning	DMX	Franklin	28 min
Apr 11, 4:31 PM CDT	Severe Thunderstorm Warning	DMX	Butler, Grundy	44 min
Apr 11, 4:35 PM CDT	Severe Thunderstorm Warning	DMX	Tama	30 min
Apr 11, 4:43 PM CDT	Severe Thunderstorm Warning	DMX	Black Hawk	37 min
Apr 11, 5:07 PM CDT	Tornado Warning	DMX	Black Hawk	23 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2001 Every severe thunderstorm warning 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; radar from the NEXRAD Level II archive.