Alert archive / Iowa / Severe Thunderstorm Warnings in 1994

Severe Thunderstorm Warning 13, NWS Des Moines, IA

April 14, 1994Story County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Apr 14, 1994, 10:55 PM CDT for Story County, Iowa. It was in force for 35 min.

The area

The counties it named.

The facts

Issued
Apr 14, 1994, 10:55 PM CDT (03:55 UTC)
Expired
Apr 14, 1994, 11:30 PM CDT
In force
35 min
Issued by
NWS Des Moines, IA
Area
Whole counties

County Story County, IA

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 3.9 hours before the alert went out and 254 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 1994-04-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 715 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 1994-04-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 60 square meters per square second.19395878Sfc1 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
715 J/kg
Mixed-layer CIN
-24 J/kg
Mixed-layer LCL
1765 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
60 m²/s²
0-3 km storm-relative helicity
129 m²/s²
Significant tornado parameter
0.1
Supercell composite
1.5

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KDSM 150401 COR
SVRDSM
IAC169-150430-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING...CORRECTED FOR CODING
NATIONAL WEATHER SERVICE DES MOINES IA
1059 PM CDT THU APR 14 1994
 
THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 1130 PM CDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN CENTRAL IOWA
 
   ...STORY COUNTY
 
AT 1058 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM IN A LINE MOVING INTO SOUTHERN STORY COUNTY. THIS
STORM WAS 25 MILES NORTH OF DES MOINES. THE STORM WAS MOVING NORTHEAST
AT 35 TO 40 MILES AN HOUR. IT WILL AFFECT THE TOWNS OF AMES...STORY
CITY AND NEVADA BETWEEN 11 PM AND 1120 PM.
 
 
WHEN THUNDERSTORMS 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.

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 14, 8:29 PM CDTSevere Thunderstorm WarningDMXTaylor31 min
Apr 14, 8:34 PM CDTSevere Thunderstorm WarningDMXCass41 min
Apr 14, 9:04 PM CDTSevere Thunderstorm WarningDMXAdair, Cass41 min
Apr 14, 9:39 PM CDTSevere Thunderstorm WarningDMXJasper, Marshall36 min
Apr 14, 9:40 PM CDTSevere Thunderstorm WarningDMXGrundy35 min
Apr 14, 9:44 PM CDTSevere Thunderstorm WarningDMXMadison, Union31 min
Apr 14, 9:47 PM CDTSevere Thunderstorm WarningDMXDallas, Guthrie43 min
Apr 14, 9:55 PM CDTSevere Thunderstorm WarningDMXPolk35 min
Apr 14, 10:08 PM CDTSevere Thunderstorm WarningDMXBlack Hawk52 min
Apr 14, 10:08 PM CDTTornado WarningDMXAdair37 min
Apr 14, 10:24 PM CDTSevere Thunderstorm WarningDMXBuchanan51 min
Apr 14, 10:26 PM CDTSevere Thunderstorm WarningDMXDallas, Polk34 min
Apr 14, 10:27 PM CDTSevere Thunderstorm WarningDMXTama48 min
Apr 14, 11:03 PM CDTTornado WarningDMXStory27 min
Apr 14, 11:04 PM CDTSevere Thunderstorm WarningDMXBlack Hawk26 min
Apr 14, 11:23 PM CDTSevere Thunderstorm WarningDMXMarshall19 min
Apr 14, 11:39 PM CDTSevere Thunderstorm WarningDMXGrundy25 min
Apr 14, 11:47 PM CDTSevere Thunderstorm WarningDMXVan Buren28 min
Apr 15, 12:09 AM CDTSevere Thunderstorm WarningDMXLinn36 min
Apr 15, 12:10 AM CDTSevere Thunderstorm WarningDMXBlack Hawk21 min
Apr 15, 12:15 AM CDTSevere Thunderstorm WarningDMXBuchanan29 min

Nearby

Severe Thunderstorm Warnings in Iowa, 1994Every severe thunderstorm warning in 1994

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.