Alert archive / Iowa / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 38, NWS Quad Cities, IA

August 29, 1990Lee County, Iowa

NWS Quad Cities, IA issued this severe thunderstorm warning at Aug 29, 1990, 1:49 AM CDT for Lee County, Iowa. It was in force for 41 min.

The area

The counties it named.

The facts

Issued
Aug 29, 1990, 1:49 AM CDT (06:49 UTC)
Expired
Aug 29, 1990, 2:30 AM CDT
In force
41 min
Issued by
NWS Quad Cities, IA
Area
Whole counties

County Lee 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

Topeka, KS (KTOP), launched 00:00Z, 6.8 hours before the alert went out and 399 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, Topeka, KS at 00:00Z on 1990-08-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3134 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, Topeka, KS at 00:00Z on 1990-08-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 138 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
3134 J/kg
Mixed-layer CIN
-79 J/kg
Mixed-layer LCL
2146 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
138 m²/s²
0-3 km storm-relative helicity
301 m²/s²
Significant tornado parameter
0.0
Supercell composite
7.9

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KMLI 290649
SVRMLI
IAC111-290730-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING 
NATIONAL WEATHER SERVICE MOLINE IL
149 AM CDT WED AUG 29 1990

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM 
WARNING EFFECTIVE UNTIL 230 AM CDT FOR PEOPLE IN THE FOLLOWING 
COUNTY

   IN THE SOUTHEAST PART OF IOWA
      LEE

AT 140 AM CDT RADAR SHOWS A SEVERE THUNDERSTORM 30 MILES WEST OF
BURLINGTON IA...MOVING SOUTHEAST AT 25 MPH.

40 TO 40 MPH WINDS AND 3/4 INCH HAIL WAS REPORTED WITH THIS
STORM NEAR BIRMINGHAM IN NORTHERN VAN BUREN COUNTY OF IOWA AT
120 AM CDT.

SOME CITIES/TOWNS IN THE PATH OF THIS STORM INCLUDE... MT HAMILL
FRANKLIN AND FORT MADISON

FOR YOUR PROTECTION GO TO A SAFE PLACE IMMEDIATELY.  STAY INDOORS
AND AVOID WINDOWS.  IF OUTDOORS...DO NOT STAND UNDER A TREE OR IN
OPEN AREAS SUCH AS A FIELD.

A SEVERE THUNDERSTORM CAN PRODUCE DAMAGING WIND OF 60 MPH OR MORE...
LARGE HAIL...FREQUENT DANGEROUS LIGHTNINGb AND HEAVY RAIN.

IF TIME PERMITS...ASK THE NEAREST LAW ENFORCEMENT AGENCY TO RELAY
YOUR REPORT OF SEVERE WEATHER TO THE NATIONAL WEATHER SERVICE.

KRAEMER

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 28, 11:30 PM CDT, 2 hours 19 minutes before
ILZ004-IAZ015-290530-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOLINE IL
1130 PM CDT TUE AUG 28 1990

AT 1120 PM CDT...RADAR WAS INDICATING A LINE OF STRONG THUNDERSTORMS
EXTENDING FROM JUST SOUTHEAST OF IOWA CITY THROUGH MUSCATINE AND INTO
ROCK ISLAND AND MOLINE.  THESE THUNDERSTORMS WERE MOVING EAST-SOUTHEAST
AT 30 MPH AND CONTAIN HEAVY RAIN AND FREQUENT LIGHTNING.  THESE STORMS
MAY ALSO CONTAIN SMALL HAIL AND GUSTY WINDS.  THESE STORMS WILL BE
MOVING THROUGH MUSCATINE COUNTY OF IOWA AND ROCK ISLAND AND NORTHERN
MERCER COUNTIES OF ILLINOIS OVER THE NEXT 45 MINUTES TO AN HOUR.

COOPER
Special weather statement, Aug 28, 11:38 PM CDT, 2 hours 11 minutes before
ILZ004-IAZ015-290530-

SPECIAL WEATHER STATEMENT...CORRECTION TO LAST LINE
NATIONAL WEATHER SERVICE MOLINE IL
1130 PM CDT TUE AUG 28 1990

AT 1120 PM CDT...RADAR WAS INDICATING A LINE OF STRONG THUNDERSTORMS
EXTENDING FROM JUST SOUTHEAST OF IOWA CITY THROUGH MUSCATINE AND INTO
ROCK ISLAND AND MOLINE.  THESE THUNDERSTORMS WERE MOVING EAST-SOUTHEAST
AT 30 MPH AND CONTAIN HEAVY RAIN AND FREQUENT LIGHTNING.  THESE STORMS
MAY ALSO CONTAIN SMALL HAIL AND GUSTY WINDS.  THESE STORMS WILL BE
MOVING THROUGH MUSCATINE COUNTY OF IOWA AND ROCK ISLAND AND NORTHERN
MERCER AND WESTERN HENRY COUNTIES OF ILLINOIS OVER THE NEXT HOUR.

COOPER

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 29, 12:26 AM CDTSevere Thunderstorm WarningDVNDes Moines, Henry, Louisa34 min
Aug 29, 2:31 AM CDTSevere Thunderstorm WarningDVNLee44 min

Nearby

Severe Thunderstorm Warnings in Iowa, 1990Every severe thunderstorm warning in 1990

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.