Alert archive / Iowa / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 9, NWS Des Moines, IA

May 2, 1997Appanoose County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at May 2, 1997, 8:11 PM CDT for Appanoose County, Iowa. It was in force for 49 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
May 2, 1997, 8:11 PM CDT (01:11 UTC)
Expired
May 2, 1997, 9:00 PM CDT
In force
49 min
Issued by
NWS Des Moines, IA
Area
Whole counties

County Appanoose County, IA

The radar

The Des Moines radar (KDMX), 131 km from the middle of the area, began a volume at 01:12 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.

What was reported inside it

TimeReportWhereRemark
May 2, 8:30 PM CDTHail 0.75Centerville, IA

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 1.2 hours before the alert went out and 221 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, Davenport, at 00:00Z on 1997-05-03Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 00:00Z on 1997-05-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 56 square meters per square second.1939587897117Sfc1 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
483 m above ground
0-6 km bulk shear
69 kt
0-1 km storm-relative helicity
56 m²/s²
0-3 km storm-relative helicity
65 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.

230 
WUUS1 KDSM 030111 RRA
SVRDSM
IAC007-030200-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
811 PM CDT FRI MAY 2 1997

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

* UNTIL 900 PM CDT
 
* SOME AREAS AFFECTED
    CINCINNATI
    NUMA
    EXLINE
    MOULTON

* AT 809 PM CDT RADAR INDICATED A SEVERE THUNDERSTORM 10 MILES SOUTHWEST
OF   CINCINNATI OR 50 SOUTHWEST OF OTTUMWA MOVING EAST AT 20 MPH.

* THE STORM WILL BE SOUTH OF CINCINNATI BY 825 PM CDT.

THIS IS A DANGEROUS STORM.  DO NOT GO OUTDOORS.




FORSTER/KUBINA

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, May 2, 3:35 PM CDT, 4 hours 36 minutes before
IAZ057-070>071-081>086-092>097-030300-

CENTRAL IOWA THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
335 PM CDT FRI MAY 2 1997

HAZARD--ISOLATED THUNDERSTORMS PRODUCING SMALL HAIL AND BRIEF HEAVY
RAINS...ALONG WITH THE POSSIBILITY OF COLD AIR FUNNELS.

AREA OF CONCERN--THE SOUTHERN QUARTER OF IOWA...ALONG AND SOUTH OF A
AUDUBON TO OTTUMWA LINE.

TIMING DETAILS--THUNDERSTORMS ARE POSSIBLE IN THE OUTLOOK AREA BETWEEN
4 AND 8 PM.

METEOROLOGICAL COMMENTS...AN AREA OF LOW PRESSURE ALOFT IS FORECAST TO
SLOWLY PUSH ACROSS THE STATE THIS EVENING AND TONIGHT. ASSOCIATED WITH
THIS UPPER LEVEL STORM SYSTEM ARE SOME FAIRLY COLD TEMPERATURES FROM
10,000 TO 20,000 FEET IN THE ATMOSPHERE. THE COMBINATION OF THE COLD
TEMPERATURES ALOFT AND SOME LOW LEVEL WARMING THAT OCCURRED OVER PARTS
OF SOUTHWEST AND EXTREME SOUTHERN IOWA THIS AFTERNOON WILL ENHANCE THE
THREAT FOR ISOLATED THUNDERSTORMS...ALONG WITH THE POSSIBILITY OF ONE
OR TWO OF THESE STORMS PRODUCING A COLD AIR FUNNEL. IN ADDITION...WITH
THE TEMPERATURES COOLING OFF IN THE UPPER ATMOSPHERE LATE THIS
AFTERNOON...FREEZING LEVELS AND WET BULB ZERO HEIGHTS WILL BE LOWERING
WHICH WILL INCREASE THE LIKELIHOOD OF HAIL WITH THE THUNDERSTORMS.

PRECAUTIONS...PEOPLE PLANNING OUTDOOR ACTIVITIES FOR LATE THIS
AFTERNOON INTO THIS EVENING SHOULD BE PREPARED FOR SCATTERED SHOWERS
AND ISOLATED THUNDERSTORMS TO DISRUPT THEIR EVENTS FOR A BRIEF PERIOD.
ALTHOUGH THE THREAT IS THERE FOR A FEW COLD AIR FUNNELS WITH THE
SHOWERS AND THUNDERSTORMS...STUDIES OF COLD AIR FUNNELS SHOW THAT THEY
RARELY TOUCH THE GROUND. THEY ARE USUALLY QUITE SMALL AND ARE NOT AS
VIOLENT AS THOSE ASSOCIATED WITH SEVERE THUNDERSTORMS. COLD AIR
FUNNELS NORMALLY PROTRUDE A FEW HUNDRED FEET DOWNWARD FROM THE PARENT
CLOUD...ROTATE OR SPIN LIKE A TOP...AND LAST FOR A FEW MINUTES BEFORE
DISSIPATING.

AT THIS TIME IT APPEARS THAT SPOTTER ACTIVATION WILL NOT BE REQUIRED
LATE THIS AFTERNOON OR EVENING.

SMITH
Special weather statement, May 2, 3:38 PM CDT, 4 hours 33 minutes before
IAZ057-070>071-081>086-092>097-030300-

CENTRAL IOWA THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
335 PM CDT FRI MAY 2 1997

HAZARD--ISOLATED THUNDERSTORMS PRODUCING SMALL HAIL AND BRIEF HEAVY
RAINS...ALONG WITH THE POSSIBILITY OF COLD AIR FUNNELS.

AREA OF CONCERN--THE SOUTHERN QUARTER OF IOWA...ALONG AND SOUTH OF A
AUDUBON TO OTTUMWA LINE.

TIMING DETAILS--THUNDERSTORMS ARE POSSIBLE IN THE OUTLOOK AREA BETWEEN
4 AND 8 PM.

METEOROLOGICAL COMMENTS...AN AREA OF LOW PRESSURE ALOFT IS FORECAST TO
SLOWLY PUSH ACROSS THE STATE THIS EVENING AND TONIGHT. ASSOCIATED WITH
THIS UPPER LEVEL STORM SYSTEM ARE SOME FAIRLY COLD TEMPERATURES FROM
10,000 TO 20,000 FEET IN THE ATMOSPHERE. THE COMBINATION OF THE COLD
TEMPERATURES ALOFT AND SOME LOW LEVEL WARMING THAT OCCURRED OVER PARTS
OF SOUTHWEST AND EXTREME SOUTHERN IOWA THIS AFTERNOON WILL ENHANCE THE
THREAT FOR ISOLATED THUNDERSTORMS...ALONG WITH THE POSSIBILITY OF ONE
OR TWO OF THESE STORMS PRODUCING A COLD AIR FUNNEL. IN ADDITION...WITH
THE TEMPERATURES COOLING OFF IN THE UPPER ATMOSPHERE LATE THIS
AFTERNOON...FREEZING LEVELS AND WET BULB ZERO HEIGHTS WILL BE LOWERING
WHICH WILL INCREASE THE LIKELIHOOD OF HAIL WITH THE THUNDERSTORMS.

PRECAUTIONS...PEOPLE PLANNING OUTDOOR ACTIVITIES FOR LATE THIS
AFTERNOON INTO THIS EVENING SHOULD BE PREPARED FOR SCATTERED SHOWERS
AND ISOLATED THUNDERSTORMS TO DISRUPT THEIR EVENTS FOR A BRIEF PERIOD.
ALTHOUGH THE THREAT IS THERE FOR A FEW COLD AIR FUNNELS WITH THE
SHOWERS AND THUNDERSTORMS...STUDIES OF COLD AIR FUNNELS SHOW THAT THEY
RARELY TOUCH THE GROUND. THEY ARE USUALLY QUITE SMALL AND ARE NOT AS
VIOLENT AS THOSE ASSOCIATED WITH SEVERE THUNDERSTORMS. COLD AIR
FUNNELS NORMALLY PROTRUDE A FEW HUNDRED FEET DOWNWARD FROM THE PARENT
CLOUD...ROTATE OR SPIN LIKE A TOP...AND LAST FOR A FEW MINUTES BEFORE
DISSIPATING.

AT THIS TIME IT APPEARS THAT SPOTTER ACTIVATION WILL NOT BE REQUIRED
LATE THIS AFTERNOON OR EVENING.

SMITH
Special weather statement, May 2, 7:58 PM CDT, 13 minutes before
IAZ095-030120-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
758 PM CDT FRI MAY 2 1997

THE SEVERE THUNDERSTORM WARNING FOR WAYNE COUNTY HAS EXPIRED.

FORSTER/KUBINA
Special weather statement, May 2, 7:59 PM CDT, 12 minutes before
IAZ095-030120-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
758 PM CDT FRI MAY 2 1997

THE SEVERE THUNDERSTORM WARNING FOR WAYNE COUNTY HAS EXPIRED.

FORSTER/KUBINA

The office that day

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

IssuedProductOfficeCountiesLasted
May 2, 7:00 PM CDTSevere Thunderstorm WarningDMXDecatur30 min
May 2, 7:22 PM CDTSevere Thunderstorm WarningDMXWayne33 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.