Alert archive / Iowa / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 158, NWS Des Moines, IA

July 18, 1990Audubon County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Jul 18, 1990, 4:29 PM CDT for Audubon County, Iowa. It was in force for 31 min.

The area

The counties it named.

The facts

Issued
Jul 18, 1990, 4:29 PM CDT (21:29 UTC)
Expired
Jul 18, 1990, 5:00 PM CDT
In force
31 min
Issued by
NWS Des Moines, IA
Area
Whole counties

County Audubon 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

Omaha, NE (KOAX), launched 12:00Z, 9.5 hours before the alert went out and 128 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, Omaha, NE at 12:00Z on 1990-07-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Omaha, NE at 12:00Z on 1990-07-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 111 square meters per square second.1939Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3632 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
111 m²/s²
0-3 km storm-relative helicity
138 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.

000 
TTAA00 KDSM 182131
SVRDSM
IAC009-182200-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
429 PM CDT WED JUL 18 1990
 
THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  500 PM CDT
FOR PEOPLE IN THE FOLLOWING COUNTY...
 
IN WEST CENTRAL IOWA
          ...AUDUBON
 
AT 428 PM...WEATHER RADAR INDICATED A SEVERE THUNDERSTORM OVER
SOUTHERN AUDUBON COUNTY NEAR BRAYTON...OR SOME 60 MILES NORTHEAST OF
COUNCIL BLUFFS.
 
THE STORM WAS DRIFTING NORTH AT 10 MILES AN HOUR...AND WILL BE
AFFECTING THE CITIES OF EXIRA...BRAYTON...HAMLIN...AND AUDUBON.
 
IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER FROM THE WEATHER IN A
S*TRONG BUILDING.  DAMAGING WIND...LARGE HAIL...VERY HEAVY RAIN...
AND DEADLY LIGHTNING ARE ALL POSSIBLE IN SEVERE THUNDERSTORMS.
STAY INSIDE AWAY FROM WINDOWS UNTIL THE STORM HAS PASSED.
 
FERRY/TRUETT

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, Jul 18, 10:49 AM CDT, 5 hours 40 minutes before
IAZALL-181630-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
1045 AM CDT WED JUL 18 1990

AT 1035 AM...SCATTERED SHOWERS AND ISOLATED STRONG THUNDERSTORMS WERE
NOW ACROSS THE NORTHEAST HALF OF IOWA...NORTHEAST OF A SIOUX CITY/DES
MOINES/OTTUMWA LINE.

THE STRONGEST STORMS WERE IN THE CENTRAL AND EAST CENTRAL COUNTIES NEAR
BOONE...STORY CITY...NEW SHARON AND WILLIAMSBURG.  AT THIS TIME...LITTLE
MORE THAN BRIEF hHEAVY RAINS AND WINDS OF 30 TO 40 MILES AN HOUR ARE
EXPECTED.

ALSO...ISOLATED THUNDERSTORMS WERE DEVELOPING ACROSS THE NORTHERN
SECTIONS OF THE DES MOINES AREA.

THE SHOWERS AND STORMS WERE MOVING SOUTHEAST AT 35 MILES AN HOUR.

KS
Special weather statement, Jul 18, 11:44 AM CDT, 4 hours 45 minutes before
IAZALL-181730-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
1140 AM CDT WED JUL 18 1990

AT 1135 AM...SCATTERED SHOWERS AND ISOLATED STRONG THUNDERSTORMS WERE
OVER THE EASTERN HALF OF IOWA...ALONG AND EAST OF A MASON CITY...
DES MOINES...LAMONI LINE.

THE STRONGEST STORMS WERE IN THE CENTRAL AND EAST CENTRAL COUNTIES
BETWEEN NEWTON AND TAMA/TOLEDO...OR FROM 40 TO 60 MILES EAST OF
DES MOINES.  THESE STORMS MAY PRODUCE BRIEF HEAVY RAINS...WINDS OF
30 TO 40 MILES AN HOUR...AND POSSIBLY SOME SMALL HAIL.

IN ADDITION...SCATTERED THUNDERSTORMS CONTINUED OVER THE EXTREME
NORTHWEST COUNTIES...BETWEEN SPENCER AND SIOUX FALLS.  ONE OF
THESE STORMS PRODUCED 5 MINUTES OF MARBLE SIZED HAIL ABOUT 25 MILES
WEST OF SPENCER NEAR SANBORN BETWEEN 1110 AND 1120 AM THIS MORNING.
ALSO...MARBLE SIZED HAIL COMPLETELY COVERED THE GROUND JUST WEST OF
SANBORN.

ALL OF THE SHOWERS AND STORMS WERE MOVING SOUTHEAST AT 30 MILES AN HOUR.

KS/TRUETT
Special weather statement, Jul 18, 12:19 PM CDT, 4 hours 10 minutes before
IAZALL-181830-

SPECIAL WEATHER STATEMENT AND WEATHER UPDATE FOR IOWA
NATIONAL WEATHER SERVICE DES MOINES IA
1215 PM CDT WED JUL 18 1990

AT 1210 PM...SCATTERED SHOWERS AND ISOLATED STRONG THUNDERSTORMS WERE
OVER THE EASTERN HALF OF IOWA...ALONG OR EAST OF A MASON CITY/DES MOINES
/LAMONI LINE.

THE STRONGEST STORMS WERE IN THE SOUTH CENTRAL...SOUTHEAST AND EAST
CENTRAL COUNTIES...BETWEEN RED ROCK LAKE AND RATHBUN LAKE...JUST EAST OF
OTTUMWA AND NEAR CEDAR RAPIDS.  THE STORMS WERE PRODUCING HEAVY RAINS
AND WINDS OF 30 TO 40 MILES AN HOUR.

IN ADDITION...SCATTERED THUNDERSTORMS CONTINUED OVER THE EXTREME
NORTHWEST COUNTIES...BETWEEN SPENCER AND SIOUX FALLS.  ALONG WITH THE
HEAVY RAINS...HAIL IS LIKELY WITH THESE STORMS.

THE SHOWERS AND STORMS WERE MOVING SOUTHEAST AT 30 MILES AN HOUR.
KS
Special weather statement, Jul 18, 12:44 PM CDT, 3 hours 45 minutes before
IAZALL-181830-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
1245 PM CDT WED JUL 18 1990

AT 1235 PM...SCATTERED SHOWERS AND ISOLATED STRONG THUNDERSTORMS
CONTINUED OVER THE EASTERN SECTIONS OF IOWA...ALONG AND EAST OF A
DECORAH...WATERLOO...DES MOINES...LAMONI LINE.

THE GREATEST CONCENTRATION OF STORMS WAS OVER THE SOUTH CENTRAL AND
SOUTHEAST COUNTIES BETWEEN OSCEOLA AND FAIRFIELD...OR FROM 50 MILES
WEST OF OTTUMWA TO ABOUT 25 MILES EAST OF OTTUMWA.  THESE STORMS WILL
PRODUCE BRIEF HEAVY RAINS...AND MAY POSSIBLY PRODUCE WINDS OF 30 TO 40
MILES AN HOUR.

SCATTERED THUNDERSTORMS ALSO REMAINED OVER THE NORTHWEST COUNTIES...
BETWEEN SPENCER AND SIOUX FALLS.  HEAVY RAINS...AND SOME HAIL...IS
ALSO LIKELY WITH THESE STORMS.

ALL OF THE SHOWERS AND STORMS WERE MOVING SOUTHEAST AT 30 MILES AN HOUR.

KS/TRUETT
Special weather statement, Jul 18, 1:14 PM CDT, 3 hours 15 minutes before
IAZALL-181900-

SPECIAL WEATHER STATEMENT AND WEATHER UPDATE FOR IOWA
NATIONAL WEATHER SERVICE DES MOINES IA
115 PM CDT WED JUL 18 1990

AT 110 PM...SCATTERED SHOWERS AND THUNDERSTORMS WERE OVER THE
SOUTHEAST THIRD OF IOWA...AS WELL AS OVER THE EXTREME NORTHWEST
COUNTIES.

IN SOUTHEAST IOWA...THE SHOWERS AND STORMS WERE GENERALLY ALONG AND
SOUTH OF A DUBUQUE...CEDAR RAPIDS...LAMONI LINE.  THE STRONG STORMS
WERE OVER THE SOUTH CENTRAL AND SOUTHEAST COUNTIES...IN A NARROW BAND
FROM OSCEOLA...THROUGH OTTUMWA...TO NEAR THE QUAD CITIES.

OVER NORTHWEST IOWA...THE THUNDERSTORMS LINGERED BETWEEN SPENCER AND
SIOUX FALLS.   HEAVY RAINS ARE LIKELY WITH THESE STORMS...AS WELL AS
SOME HAIL.

THE SHO9WERS AND STORMS WERE MOVING EAST-SOUTHEAST AT 30 MILES AN HOUR.
<
KS/TRUETT
Special weather statement, Jul 18, 1:39 PM CDT, 2 hours 50 minutes before
IAZALL-181930-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
140 PM CDT WED JUL 18 1990

AT 135 PM...SCATTERED SHOWERS AND THUNDERSTORMS WERE OVER THE
SOUTHEAST THIRD OF IOWA...AS WELL AS OVER THE EXTREME NORTHWEST IOWA.

IN SOUTHEAST IOWA...THE SHOWERS AND STORMS WERE GENERALLY ALONG AND
SOUTH OF A DUBUQUE...CEDAR RAPIDS...LAMONI LINE.  THE STRONG STORMS
WERE OVER THE EXTREME SOUTH CENTRAL AND SOUTHEAST COUNTIES...IN A
NARROW BAND FROM JUST NORTH OF LAMONI...TO JUST SOUTH OF OTTUMWA...
TO NEAR THE QUAD CITIES.

THE SHOWERS AND STORMS WERE MOVING SOUTHEAST AT 30 MILES AN HOUR.

OVER NORTHWEST IOWA...THE THUNDERSTORMS WERE ROUGHLY ALONG AND WEST OF
A SKPENCER...SIOUX CITY LINE.  THE STRONGEST STORM WAS 15 MILES SOUTH
OF SPENCER.
<
THE STORMS OVER NORTHWEST IOWA WERE MOVING EAST AT 30 MILES AN HOUR.

KS/TRUETT

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.