Alert archive / Iowa / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 108, NWS Des Moines, IA

August 24, 1997Decatur County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Aug 24, 1997, 10:38 PM CDT for Decatur County, Iowa. It was in force for 32 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 24, 1997, 10:38 PM CDT (03:38 UTC)
Expired
Aug 24, 1997, 11:10 PM CDT
In force
32 min
Issued by
NWS Des Moines, IA
Area
Whole counties

County Decatur County, IA

The radar

The Des Moines radar (KDMX), 111 km from the middle of the area, began a volume at 03:40 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.

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 3.6 hours before the alert went out and 226 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 1997-08-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 4736 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, Omaha, NE at 00:00Z on 1997-08-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 46 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
4736 J/kg
Mixed-layer CIN
-3 J/kg
Mixed-layer LCL
1163 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
46 m²/s²
0-3 km storm-relative helicity
87 m²/s²
Significant tornado parameter
0.0
Supercell composite
3.6

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KDSM 250337 RRA
SVRDSM
IAC053-250410-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
1038 PM CDT SUN AUG 24 1997

* SEVERE THUNDERSTORM WARNING FOR
  SOUTHERN DECATUR COUNTY - SOUTH CENTRAL IOWA

* UNTIL 1110 PM CDT
 
* SOME AREAS AFFECTED
    LAMONI
    DAVIS CITY
    PLEASANTON

* AT 1035 PM CDT RADAR INDICATED A SEVERE THUNDERSTORM 10 MILES NORTH
  OF LAMNOI OR 60 MILES SOUTH OF DES MOINES MOVING SOU0TH AT 20 MPH.

* THE STORM WILL BE IN LAMNOI BY 1050 PM CDT.

THIS IS A DANGEROUS STORM.  DO NOT GO OUTDOORS.




FORSTER/SMITH

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

Local storm report, Aug 24, 5:10 PM CDT, 5 hours 28 minutes before
PRELIMINARY LOCAL STORM REPORT...FROM SATURDAY EVENING
NATIONAL WEATHER SERVICE DES MOINES IA
510 PM CDT SUN AUG 24 1997

TIME(CDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

1040 PM    DIKE                      IA   60 MPH WINDS WITH
08/23/97   GRUNDY                         SEVERAL TREE LIMBS DOWN

1054 PM    HUDSON                    IA   .75 INCH HAIL
08/23/97   BLACK HAWK

1120 PM    2 N TRAER                 IA   .75 INCH HAIL
08/23/97   TAMA

SMITH
Local storm report, Aug 24, 5:12 PM CDT, 5 hours 26 minutes before
PRELIMINARY LOCAL STORM REPORT...FROM SATURDAY EVENING
NATIONAL WEATHER SERVICE DES MOINES IA
510 PM CDT SUN AUG 24 1997

TIME(CDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

1040 PM    DIKE                      IA   60 MPH WINDS WITH
08/23/97   GRUNDY                         SEVERAL TREE LIMBS DOWN

1054 PM    HUDSON                    IA   .75 INCH HAIL
08/23/97   BLACK HAWK

1120 PM    2 N TRAER                 IA   .75 INCH HAIL
08/23/97   TAMA

SMITH
Special weather statement, Aug 24, 7:00 PM CDT, 3 hours 38 minutes before
IAZ061-062-074-075-085-086-096-097-250100-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
700 PM CDT SUN AUG 24 1997

...SEVERE THUNDERSTORM WATCH CANCELLED...

THE SEVERE THUNDERSTORM WATCH THAT WAS IN EFFECT FOR PARTS OF
CENTRAL AND SOUTHEAST IOWA HAS BEEN CANCELLED. THE WATCH IS NO LONGER
IN EFFECT FOR THE COUNTIES OF NEWTON...POWESHIEK...MARION...MAHASKA...
MONROE...WAPELLO...APPANOOSE AND DAVIS.

REPEATING...THE SEVERE THUNDERSTORM WATCH (715) HAS BEEN CANCELLED
FOR A PORTION OF CENTRAL AND SOUTHEAST IOWA.

SMITH
Special weather statement, Aug 24, 7:05 PM CDT, 3 hours 33 minutes before
IAZ061-062-074-075-085-086-096-097-250100-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
700 PM CDT SUN AUG 24 1997

...SEVERE THUNDERSTORM WATCH CANCELLED...

THE SEVERE THUNDERSTORM WATCH THAT WAS IN EFFECT FOR PARTS OF
CENTRAL AND SOUTHEAST IOWA HAS BEEN CANCELLED. THE WATCH IS NO LONGER
IN EFFECT FOR THE COUNTIES OF NEWTON...POWESHIEK...MARION...MAHASKA...
MONROE...WAPELLO...APPANOOSE AND DAVIS.

REPEATING...THE SEVERE THUNDERSTORM WATCH (#715) HAS BEEN CANCELLED
FOR A PORTION OF CENTRAL AND SOUTHEAST IOWA.

SMITH

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 24, 10:05 PM CDTSevere Thunderstorm WarningDMXDecatur35 min
Aug 24, 10:46 PM CDTSevere Thunderstorm WarningDMXRinggold34 min
Aug 24, 11:22 PM CDTSevere Thunderstorm WarningDMXRinggold18 min
Aug 24, 11:47 PM CDTSevere Thunderstorm WarningDMXRinggold18 min

Nearby

Severe Thunderstorm Warnings in Iowa, 1997Every severe thunderstorm warning 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.