Alert archive / Iowa / Severe Thunderstorm Warnings in 1989

Severe Thunderstorm Warning 39, NWS Quad Cities, IA

August 4, 1989Delaware County, Iowa

NWS Quad Cities, IA issued this severe thunderstorm warning at Aug 4, 1989, 11:26 PM CDT for Delaware County, Iowa. It was in force for 34 min.

The area

The counties it named.

The facts

Issued
Aug 4, 1989, 11:26 PM CDT (04:26 UTC)
Expired
Aug 5, 1989, 12:00 AM CDT
In force
34 min
Issued by
NWS Quad Cities, IA
Area
Whole counties

County Delaware County, IA

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

Peoria Regional, IL (KPIA), launched 00:00Z, 4.4 hours before the alert went out and 248 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, Peoria Regional, IL at 00:00Z on 1989-08-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3854 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Peoria Regional, IL at 00:00Z on 1989-08-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 19 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
3854 J/kg
Mixed-layer CIN
-48 J/kg
Mixed-layer LCL
1122 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
19 m²/s²
0-3 km storm-relative helicity
72 m²/s²
Significant tornado parameter
0.6
Supercell composite
3.5

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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.

In the hours before

Special weather statement, Aug 4, 8:43 PM CDT, 2 hours 43 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DUBUQUE IA
843 PM CDT FRI AUG 4 1989

...SEVERE THUNDERSTORM WATCH UNTIL 1100 PM CDT...

AT 840 PM CDT WEATHER RADAR SHOWED THAT THE FIRST ROUND OF SEVERE
THUNDERSTORMS HAD MOVED SOUTHEAST AND OUT OF THE TRI-STATE AREA.

HOWEVER...ANOTHER AREA OF STRONG THUNDERSTORMS WAS MOVING TOWARD THE
NORTHWEST PART OF THE TRI-STATE AREA AND WILL MOVE INTO NORTHERN GRANT
AND NORTHERN CLAYTON COUNTIES BY 845 PM CDT.

THESE STRONG THUNDERSTORMS ARE PRODUCING LARGE HAIL...DAMAGING WIND
DANGEROUS LIGHTNING...AND VERY HEAVY RAIN.

PERSONS IN NORTHERN GRANT AND CLAYTON COUNTIES SHOULD REMAIN ALERT
FOR CHANGING WEATHER CONDITIONS AND SEEK INDOOR SHELTER IF SEVERE
WEATHER APPROACHES.
COUCH
Local storm report, Aug 4, 9:21 PM CDT, 2 hours 5 minutes before
LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DUBUQUE IA
921 PM CDT FRI AUG 4 1989

...PRELIMINARY REPORT FOR THE EVENING OF AUG 4,1989

TIME OF EVENT     EVENT
614 PM            DELAWARE COUNTY...DES OFFICE...GOLFBALL SIZE
                  HAIL...WIND 50 TO 60 MPH...AND FUNNEL CLOUDS
                  SOUTHEAST OF DELHI.
629 PM CDT        DELAWARE COUNTY...DES OFFICE...GOLFBALL SIZE
                  HAIL IN EARLSVILLE.
655 PM CDT        FUNNEL CLOUD WEST OF WORTHINGTON.

600 PM CDT THRU   NUMEROUS REPORTS OF PEA TO GOLFBALL SIZE HAIL
700 PM CDT        ACROSS DELAWARE COUNTY.

COUCH
Special weather statement, Aug 4, 11:09 PM CDT, 17 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DUBUQUE IA
1105 PM CDT FRI AUG 4 1989

...SEVERE THUNDERSTORM WATCH UNTIL 500 AM CDT...
...SEVERE THUNDERSTORM WARNING FOR LAFAYETTE COUNTY IN SOUTHWEST
WISCONSIN CANCELLED...

THE SEVERE THUNDERSTORM WARNING IS CANCELLED FOR LAFAYETTE COUNTY
IN SOUTHWEST WISCONSIN.  THE SEVERE WEATHER MOVED SOUTHEAST OUT
OF THE COUNTY.

A THUNDERSTORM MOVED INTO THE NORTHWEST PART OF DELAWARE COUNTY 45
MILES WEST OF DUBUQUE NORTH OF THE CITY OF DUNDEE.

THE THUNDERSTORM WAS PRODUCING SOME HEAVY RAIN...FREQUENT LIGHTNING
AND SOME SMALL HAIL.

A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR ALL THE TRI-STATE AREA
WITH THE EXCEPTION OF GRANT AND LAFAYETTE C
OUNTIES IN SOUTHWEST
WISCONSIN.

SEVERE WEATHER IS POSSIBLE IN OR CLOSE TO THE WATCH AREA...AND IF
SEVERE WEATHER IS SIGHTED...TAKE COVER IMMEDIATELY.

KOWALSKI

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 4, 7:03 PM CDTSevere Thunderstorm WarningDVNDubuque57 min
Aug 4, 7:33 PM CDTSevere Thunderstorm WarningDVNJackson27 min
Aug 4, 9:10 PM CDTSevere Thunderstorm WarningDVNClayton65 min
Aug 5, 11:07 AM CDTSevere Thunderstorm WarningDVNCedar, Louisa, Muscatine68 min
Aug 5, 11:09 AM CDTSevere Thunderstorm WarningDVNJones66 min
Aug 5, 11:43 AM CDTSevere Thunderstorm WarningDVNJackson32 min
Aug 5, 11:44 AM CDTSevere Thunderstorm WarningDVNClinton, Scott46 min
Aug 5, 11:44 AM CDTSevere Thunderstorm WarningDVNMuscatine46 min

Nearby

Severe Thunderstorm Warnings in Iowa, 1989Every severe thunderstorm warning in 1989

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.