Alert archive / Iowa / Tornado Warnings in 1997

Tornado Warning 28, NWS Quad Cities, IA

June 21, 1997Delaware County, Linn County, Iowa

NWS Quad Cities, IA issued this tornado warning at Jun 21, 1997, 1:20 AM CDT for Delaware County, Linn County, Iowa. It was in force for 60 min. 8 reports 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
Jun 21, 1997, 1:20 AM CDT (06:20 UTC)
Expired
Jun 21, 1997, 2:20 AM CDT
In force
60 min
Issued by
NWS Quad Cities, IA
Area
Whole counties

Counties Delaware County, IA, Linn County, IA

The radar

The Quad Cities radar (KDVN), 105 km from the middle of the area, began a volume at 06:07 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

TimeReportWhereRemark
Jun 21, 1:28 AM CDTThunderstorm Wind 60Center Pt, IATrees downed.
Jun 21, 1:37 AM CDTThunderstorm Wind 60Central City, IANumerous trees and branches down.
Jun 21, 1:40 AM CDTHail 1.75Coggon, IA
Jun 21, 1:42 AM CDTThunderstorm Wind 57Troy Mills, IA65 mph wind gust reported.
Jun 21, 1:42 AM CDTHail 1.75Prairieburg, IA
Jun 21, 1:42 AM CDTThunderstorm Wind 57Prairieburg, IAWinds downed a local landmark 80 foot tall Cedar tree. The tree damaged the roof of a vacant, soon to be demolished, house.
Jun 21, 1:57 AM CDTThunderstorm Wind 52Hopkinton, IA60 mph wind gust reported by Fire Department.
Jun 21, 1:57 AM CDTHail 1.25Ryan, 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.

IssuedProductOfficeLasted
Jun 20, 11:45 PM CDTSevere Thunderstorm WatchSPC4 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 6.3 hours before the alert went out and 109 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 00:00Z on 1997-06-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 4926 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 00:00Z on 1997-06-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 67 square meters per square second.193958Sfc1 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
4926 J/kg
Mixed-layer CIN
-12 J/kg
Mixed-layer LCL
969 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
67 m²/s²
0-3 km storm-relative helicity
216 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.

431 
WFUS1 KMLI 210622 RRA
TORMLI
IAC055-113-210720-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
120 AM CDT SAT JUN 21 1997

* TORNADO WARNING FOR
  DELAWARE COUNTY IN NORTHEASTERN IOWA
  LINN COUNTY IN EAST CENTRAL IOWA

* UNTIL 220 AM CDT
 
* SOME LOCATIONS AFFECTED
  TROY MILLS                         AROUND 120 AM CDT
  PARIS                              AROUND 135 AM CDT
  COGGON                             AROUND 140 AM CDT
  CENTRAL CITY                       AROUND 140 AM CDT
  RYAN                               AROUND 145 AM CDT

* AT 119 AM CDT...A POSSIBLE TORNADO WAS INDICATED BY QUAD CITIES
  IA DOPPLER RADAR 22 MILES NORTH OF CEDAR RAPIDS OR 3 MILES
  NORTHWEST OF TROY MILLS MOVING EAST AT 25 MPH.
 
IF YOU LIVE IN THE PATH OF THIS STORM...SEEK SHELTER IMMEDIATELY
THIS SEVERE STORM HAS HAD A HISTORY OF PRODUCING TORNADOES AND
WINDS UP TO 80 MPH.  

IF YOU ARE IN THE PATH OF A TORNADO...THE SAFEST PLACE TO BE IS
IN A BASEMENT. GET UNDER A WORKBENCH OR PIECE OF STURDY
FURNITURE. IF NO BASEMENT IS AVAILABLE...FIND SHELTER IN AN
INTERIOR ROOM SUCH AS A CLOSET ON THE LOWEST FLOOR. USE
BLANKETS...PILLOWS...OR CUSHIONS TO COVER YOUR BODY. AVOID
WINDOWS.

TEH/PAB

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 20, 11:32 PM CDTSevere Thunderstorm WarningDVNDubuque63 min
Jun 21, 12:51 AM CDTTornado WarningDVNBuchanan64 min
Jun 21, 1:04 AM CDTSevere Thunderstorm WarningDVNBenton61 min
Jun 21, 1:46 AM CDTTornado WarningDVNJones64 min
Jun 21, 1:52 AM CDTTornado WarningDVNDubuque63 min
Jun 21, 2:05 AM CDTSevere Thunderstorm WarningDVNIowa, Johnson65 min
Jun 21, 2:20 AM CDTSevere Thunderstorm WarningDVNJackson60 min
Jun 21, 3:58 AM CDTSevere Thunderstorm WarningDVNKeokuk62 min
Jun 21, 4:01 AM CDTSevere Thunderstorm WarningDVNWashington59 min
Jun 21, 4:10 AM CDTSevere Thunderstorm WarningDVNJefferson65 min
Jun 21, 4:19 AM CDTSevere Thunderstorm WarningDVNHenry, Louisa61 min
Jun 21, 4:46 AM CDTSevere Thunderstorm WarningDVNMuscatine64 min
Jun 21, 4:53 AM CDTTornado WarningDVNJones47 min
Jun 21, 4:55 AM CDTSevere Thunderstorm WarningDVNCedar45 min
Jun 21, 4:56 AM CDTSevere Thunderstorm WarningDVNDes Moines49 min
Jun 21, 5:07 AM CDTSevere Thunderstorm WarningDVNClinton, Scott58 min
Jun 21, 5:22 AM CDTSevere Thunderstorm WarningDVNJackson48 min

Nearby

Tornado Warnings in Iowa, 1997Every tornado warning in 1997Tornadoes in 1997

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.