Alert archive / Iowa / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 114, NWS Des Moines, IA

October 8, 1997Adair County, Cass County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Oct 8, 1997, 9:50 PM CDT for Adair County, Cass County, Iowa. It was in force for 35 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
Oct 8, 1997, 9:50 PM CDT (02:50 UTC)
Expired
Oct 8, 1997, 10:25 PM CDT
In force
35 min
Issued by
NWS Des Moines, IA
Area
Whole counties

Counties Adair County, IA, Cass County, IA

The radar

The Des Moines radar (KDMX), 93 km from the middle of the area, began a volume at 02:52 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Oct 8, 6:45 PM CDTTornado WatchSPC5 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 2.8 hours before the alert went out and 139 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 1997-10-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 428 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 1997-10-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 286 square meters per square second.1939587897Sfc1 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
428 J/kg
Mixed-layer CIN
-44 J/kg
Mixed-layer LCL
902 m above ground
0-6 km bulk shear
73 kt
0-1 km storm-relative helicity
286 m²/s²
0-3 km storm-relative helicity
298 m²/s²
Significant tornado parameter
0.0
Supercell composite
3.3

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KDSM 090251 RRA
SVRDSM
IAC001-029-090325-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
950 PM CDT WED OCT 8 1997

* SEVERE THUNDERSTORM WARNING FOR
  ADAIR COUNTY - SOUTHWESTERN IOWA
  SOUTHEASTERN CASS COUNTY - SOUTHWESTERN IOWA

* UNTIL 1025 PM CDT
 
* SOME AREAS AFFECTED
    MASSENA
    BRIDGEWATER
    FONTANELLE
    GREENFIELD

* AT 950 PM CDT RADAR INDICATED A SEVERE THUNDERSTORM NEAR MASSENA OR
  80 MILES SOUTHWEST OF DES MOINES MOVING NORTHEAST AT 50 MPH.

* THE STORM WILL BE OPEN COUNTRY OF WESTERN ADAIR BY 1000 PM.

DAMAGING WINDS OF 60 MPH ARE LIKELY WITH THIS STORM.  A TORNADO WATCH IS
ALSO IN EFFECT.  REMEMBER...SEVERE THUNDERSTO|RMS CAN AND OCCASIONALLY DO
PRODUCE TORNADOES WITH LITTLE OR NO ADVANCE WARNING.


KULA

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, Oct 8, 5:10 PM CDT, 4 hours 40 minutes before
IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086-
092>097-090200-

CENTRAL IOWA THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
510 PM CDT WED OCT 8 1997

HAZARD--A SQUALL LINE OF THUNDERSTORMS...SEVERAL OF WHICH COULD BE
SEVERE WITH WIND GUSTS WELL IN EXCESS OF 60 MPH.

AREA OF CONCERN--THE ENTIRE FORECAST AREA.

TIMING DETAILS--SCATTERED SHOWERS WILL MOVE NORTHEAST THROUGH EASTERN
IOWA EARLY THIS EVENING. THE LINE OF THUNDERSTORMS WILL MOVE INTO
WESTERN IOWA BY 600 PM THEN INTO EASTERN IOWA AFTER 800 PM.

METEOROLOGICAL COMMENTS--ONE LINE OF THUNDERSTORMS WAS LOCATED FROM
NORTHEAST KANSAS INTO SOUTHEAST NEBRASKA AND IT WAS MOVING NORTHEAST AT
50 MPH.  ANOTHER LINE OF THUNDERSTORMS WAS MOVING THROUGH NORTH CENTRAL
AND NORTHEAST NEBRASKA.  THERE HAVE BEEN SEVERAL REPORTS OF WIND GUSTS
BETWEEN 60 AND 75 MPH WITH THIS LINE.  THE STRONG WINDS HAVE ALSO PICKED
UP A LOT OF DUST WHICH IS EVIDENT IN VISIBLE SATELLITE IMAGERY...SO
BLOWING DUST WILL ARRIVE WITH THESE STORMS AND REDUCE VISIBILITIES.
SEVERE WEATHER WATCHES HAVE BEEN ISSUED FOR PORTIONS OF NEBRASKA...
KANSAS AND MISSOURI FOR THIS EVENING.  THE COLD FRONT HAS BEEN SLOW TO
MOVE TODAY...BUT IT IS EXPECTED TO ACCELERATE EASTWARD THIS EVENING.
THIS LINE OF STORMS WILL CONTINUE TO TAP INTO THE 60 TO 80 MPH JUST
ABOVE THE SURFACE AS THEY MARCH EAST INTO IOWA TONIGHT.  STRONG WINDS
CONTINUE TO BE THE MAIN THREAT FROM THESE STORMS...HOWEVER THERE
CONTINUES TO BE JUST ENOUGH SHEAR TO ALLOW A WEAK TORNADO TO DEVELOP.

PRECAUTIONS--SPOTTER ACTIVATION IS LIKELY TONIGHT.  CONTINUE TO MONITOR
CENTRAL IOWA THUNDERSTORM OUTLOOKS FOR THE LATEST INFORMATION.  TAKE
TIME NOW TO SECURE OUTDOOR OBJECTS THAT MAY BE SUSCEPTIBLE TO THE WIND.

STARK

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.