Alert archive / Iowa / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 162, NWS Des Moines, IA

August 10, 1990Boone County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Aug 10, 1990, 12:49 AM CDT for Boone County, Iowa. It was in force for 34 min.

The area

The counties it named.

The facts

Issued
Aug 10, 1990, 12:49 AM CDT (05:49 UTC)
Expired
Aug 10, 1990, 1:23 AM CDT
In force
34 min
Issued by
NWS Des Moines, IA
Area
Whole counties

County Boone 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 00:00Z, 5.8 hours before the alert went out and 218 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 00:00Z on 1990-08-10Temperature 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 00:00Z on 1990-08-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 23 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3582 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
23 m²/s²
0-3 km storm-relative helicity
74 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 100550
SVRDSM
IAC015-049-100630-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
1249 AM CDT FRI AUG 10 1990
 
THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  130 AM CDT
FOR PEOPLE IN THE FOLLOWING COUNTIES...
 
IN CENTRAL IOWA
          ...SOUTHWESTERN BOONE...DALLAS
 
AT 1245 AM...WEATHER RADAR INDICATED A SEVERE THUNDERSTORM OVER
SOUTHWEST BOONE COUNTY...JUST SOUTHWEST OF OGDEN...OR ABOUT 40
MILES NORTHWEST OF DES MOINES.
 
THE STORM WAS MOVING SOUTH AT 25 MILES AN HOUR...AND WILL BE AFFECTING
THE CITIES OF BERKLEY...PERRY...DAWSON...WOODWARD...AND MINBURN.
 
 
 
WHEN THUNDERSTORMSs ARE OCCURRING...PEOPLE SHOULD MOVE INSIDE A
STRONG BUILDING.  DO NOT STAND BY WINDOWS.  DON'T USE TELEPHONES
OR ELECTRICAL APPLIANCES UNLESS IN AN EMERGENCY UNTIL THE STORM
HAS PASSED.  MOTORISTS SHOULD NOT DRIVE INTO LOW WATER CROSSINGS.

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 9, 9:15 PM CDT, 3 hours 34 minutes before
IAZ002-003-007-080300-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE WATERLOO IA
910 PM CDT THU AUG 8 1990

AT 905 PM CDT SHOWERS AND THUNDERSTORMS WERE OCCURRING IN A 25 MILE
WIDE BAND FROM 5 MILES NORTH OF HAMPTON TO DECORAH. THE STRONGEST
STORMS WERE IN SOUTHEAST CERRO GORDO COUNTY NEAR THE TOWN OF DOUGHERTY
AND SOUTHERN FLOYD COUNTY BETWEEN MARBLE ROCK AND CHARLES CITY. THESE
STORMS WILL PRODUCE HEAVY RAINS...DEADLY LIGHTNING...AND SOME SMALL
HAIL. THESE STORMS WERE MOVING TO THE SOUTH AT 20 MILES AN HOUR.

THESE STORMS WILL CONTINUE TO MOVE SOUTH INTO FRANKLIN AND BUTLER
COUNTIES AND AFFECT THE CITIES OF HAMPTON...SHEFFIELD...CLARKSVILLE
AND GREENE.

PEOPLE SHOULD BE ALERT FOR TMHREATENING WEATHER AND MOVE TO A PLACE
OF SAFETY IF IN THE PATH OF THESE STORMS.

COLLAR
Special weather statement, Aug 9, 10:06 PM CDT, 2 hours 43 minutes before
IAZ002-003-007-100400-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE WATERLOO IA
1005 PM CDT THU AUG 9 1990

AT 955 PM CDT SHOWERS AND THUNDERSTORMS WERE OCCURRING IN A 25 MILE
WIDE BAND FROM 5 MILES NORTH OF GRUNDY CENTER THROUGH NEW HARTFORD TO
10 MILES NORTHEAST OF WAVERLY. THESE STORMS WILL PRODUCE HEAVY RAINS
...DEADLY LIGHTNING...AND POSSIBLY SOME SMALL HAIL. THE STORMS WERE
MOVING TO THE SOUTH AT 20 TO 25 MILES AN HOUR.

THESE STORMS WILL CONTINUE TO MOVE THROUGH GRUNDY AND BLACK HAWK COUNTY
AND AFFECT THE CITIES OF WATERLOO...CEDAR FALLS..AND THE GRUNDY CENTER
AREA BETWEEN 1000 AND 1100 PM CDT.

PEOPLE SHOULD BE ALERT FOR THREATENING WEATHER AND MOVE TO A PLACE
OF SAFETY IF IN THE PATH OF THESE STORMS.

COLLAR
Special weather statement, Aug 9, 11:42 PM CDT, 1 hour 7 minutes before
IAZALL-100531-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
1135 PM CDT THU AUG 9 1990

STRONG THUNDERSTORMS HAVE MOVED INTO CENTRAL IOWA.  AT 1125 PM...A
NARROW BAND OF THUNDERSTORMS WITH EXTREMELY HEAVY RAINS AND SMALL HAIL
EXTENDED FROM STORY CITY...NORTH OF AMES TO MARSHALLTOWN...NORTHEAST OF
DES MOINES.   WINDS OF 35 TO 45 MILES AN HOUR WERE ALSO OCCURRING WITH
THESE STORMS.

THE STORMS WERE MOVING SOUTH AT 25 MILES AN HOUR.  BY 1230 AM THESE
STORMS WILL STRETCH FROM SAYLORVILLE LAKE NORTH OF DES MOINES THROUGH
NEWTON TO NEAR MONTEZUMA...55 MILES EAST OF DES MOINES.

OTHER SHOWERS AND SCATTERED THUNDERSTORMS WERE OVER EAST CENTRAL IOWA
FROM WEST OF CEDAR RAPIDS NEAR TOLEDO AND BROOKLYN TO CEDAR RAPIDS.
THESE SHOWERS AND THUNDERSTORMS WERE ALSO MOVING SOUTH AT 25 MILES AN
HOUR.
DLF
Special weather statement, Aug 10, 12:18 AM CDT, 31 minutes before
IAZ010-100630-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1215 AM CDT FRI AUG 10 1990

...STRONG THUNDERSTORMS MOVING THROUGH CENTRAL IOWA...

AT 1215 AM...STRONG THUNDERSTORMS WERE MOVING THROUGH CENTRAL IOWA.
THE LEADING EDGE OF THE STORMS EXTENDED FROM JUST SOUTH OF BOONE...
ABOUT 30 MILES NORTHWEST OF DES MOINES...TO NEAR SAYLORVILLE LAKE...
10 MILES NORTH OF DES MOINES...TO NEAR PELLA...30 MILES SOUTHEAST
OF DES MOINES.

THE STORMS WERE MOVING SOUTH AT 25 MILES AN HOUR...AND WILL REACH THE
DES MOINES AREA BETWEEN 1230 AM AND 1 AM.  FREQUENT DANGEROUS
LIGHTNING...AND EXTREMELY HEAVY RAINS OF UP TO AN INCH IN AN HOUR
CAN BE EXPECTED WITH THE STORMS PASSAGE.  SOME JSMALL HAIL...AND WINDS
OF 30 TO 40 MILES AN HOUR...ARE ALSO POSSIBLE.

TRUETT
Special weather statement, Aug 10, 12:37 AM CDT, 12 minutes before
IAZALL-100630-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
1235 AM CDT FRI AUG 10 1990

AT 1235 AM...STRONG THUNDERSTORMS CONTINUED OVER CENTRAL IOWA.  THE
LEADING EDGE OF THE STORMS EXTENDED FROM ABOUT 50 MILES NORTHWEST OF
DES MOINES NEAR BOONE...TO DES MOINES...TO 30 MILES SOUTHEAST OF
DES MOINES NEAR PELLA.

THE STORMS WERE MOVING SOUTH AT 25 MILES AN HOUR...AND WILL PRODUCE
FREQUENT LIGHTNING...AND UP TO AN INCH OF RAIN.  WINDS OF 30 TO
40 MILES AN HOUR...AND SOME SMALL HAIL...IS ALSO POSSIBLE.

OTHER SHOWERS WERE OVER EAST CENTRAL AND SOUTHEAST IOWA...BETWEEN
CEDAR RAPIDS AND OTTUMWA.  THESE SHOWERS WERE ALSO MOVING SOUTH AT
25 MILES AN HOUR.
b
FERRY/TRUETT

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 9, 10:11 PM CDTSevere Thunderstorm WarningDMXHardin34 min
Aug 9, 11:44 PM CDTSevere Thunderstorm WarningDMXStory31 min
Aug 10, 12:49 AM CDTSevere Thunderstorm WarningDMXDallas41 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.