Alert archive / Iowa / Severe Thunderstorm Warnings in 1997
Severe Thunderstorm Warning 46, NWS Des Moines, IA
NWS Des Moines, IA issued this severe thunderstorm warning at Jun 20, 1997, 7:25 AM CDT for Butler County, Iowa. It was in force for 35 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
- Jun 20, 1997, 7:25 AM CDT (12:25 UTC)
- Expired
- Jun 20, 1997, 8:00 AM CDT
- In force
- 35 min
- Issued by
- NWS Des Moines, IA
- Area
- Whole counties
County Butler County, IA
The radar
The Des Moines radar (KDMX), 135 km from the middle of the area, began a volume at 12:27 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
| Time | Report | Where | Remark |
|---|---|---|---|
| Jun 20, 7:25 AM CDT | Hail 1 | Aplington, 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 watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Jun 20, 4:15 AM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
The nearest sounding before it
Davenport, (KDVN), launched 12:00Z, 0.4 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.
- Mixed-layer CAPE
- 2894 J/kg
- Mixed-layer CIN
- -77 J/kg
- Mixed-layer LCL
- 766 m above ground
- 0-6 km bulk shear
- 23 kt
- 0-1 km storm-relative helicity
- 218 m²/s²
- 0-3 km storm-relative helicity
- 188 m²/s²
- Significant tornado parameter
- 1.6
- Supercell composite
- 12.0
The text
As transmitted, in the capitals the NWS used until 2016.
000
TTAA00 KDSM 201224 RRA
SVRDSM
IAC023-201300-
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
725 AM CDT FRI JUN 20 1997
* SEVERE THUNDERSTORM WARNING FOR
SOUTHERN BUTLER COUNTY - NORTHEASTERN IOWA
* UNTIL 800 AM CDT
* SOME AREAS AFFECTED
APLINGTON
PARKERSBURG
NEW HARTFORD
* AT 723 AM CDT STORM SPOTTERS REPORTED A SEVERE THUNDERSTORM 5 MILES
WEST OF APLINGTON OR 30 MILES WEST OF WATERLOO MOVING EAST AT 40 MPH.
* THE STORM WILL BE NEAR PARKERSBURG BY 735 AM CDT.
1 INCH HAIL SOUTHWEST BUTHER COUNTY AT 725 AM VIA NWS SPOTTER.
THIS IS A DANGEROUS STORM. DO NOT GO OUTDOORS.
FELDT
&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, Jun 20, 2:05 AM CDT, 5 hours 20 minutes before
PRELIMINARY LOCAL STORM REPORT NATIONAL WEATHER SERVICE DES MOINES IA 205 AM CDT FRI JUN 20 1997 TIME(CDT) .....CITY LOCATION..... ST ...EVENT/REMARKS... DATE(CDT) ....COUNTY LOCATION.... 0123 AM CUMBERLAND IA 1.00 INCH HAIL 06/20/97 CASS JOHNSON
Local storm report, Jun 20, 2:07 AM CDT, 5 hours 18 minutes before
PRELIMINARY LOCAL STORM REPORT NATIONAL WEATHER SERVICE DES MOINES IA 205 AM CDT FRI JUN 20 1997 TIME(CDT) .....CITY LOCATION..... ST ...EVENT/REMARKS... DATE(CDT) ....COUNTY LOCATION.... 0123 HAM CUMBERLAND IA 1.00 INCH HAIL 06/20/97 CASS JOHNSON
Special weather statement, Jun 20, 2:28 AM CDT, 4 hours 57 minutes before
IAZ004>006-015-016-023>025-033>036-044-201000- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DES MOINES IA 228 AM CDT FRI JUN 20 1997 THE SEVERE THUNDERSTORM WATCH 482 HAS BEEN ALLOWED TO EXPIRE. THERE ARE SHOWERS AND THUNDERSTORMS MOVING INTO NORTHWEST IOWA AT THIS TIME BUT NO SEVERE WEATHER IS EXPECTED IN THIS AREA. REMEMBER SEVERE THUNDERSTORM WATCH 485 REMAINS IN EFFECT FOR SOUTHWEST AND CENTRAL IOWA UNTIL 6AM. BARLOW
Special weather statement, Jun 20, 6:45 AM CDT, 40 minutes before
IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086- 092>097-201800- CENTRAL IOWA THUNDERSTORM OUTLOOK NATIONAL WEATHER SERVICE DES MOINES IA 645 AM CDT FRI JUN 20 1997 HAZARD -- ISOLATED SEVERE THUNDERSTORMS NORTHERN IOWA THIS MORNING CAPABLE OF LARGE HAIL AND DAMAGING WINDS. A RISK OF SEVERE STORMS ACROSS MOST OF THE AREA NORTH OF A LAMONI TO OTTUMWA LINE THIS AFTERNOON. TIMING AND AREA OF CONCERN -- THROUGH 1000 AM FOR NORTHERN IOWA THIS MORNING. AFTER 3 PM FOR THE AFTERNOON THUNDERSTORMS. METEOROLOGICAL COMMENTS -- A COLD FRONT WAS FORCED SOUTH THIS MORNING DUE TO STRONG CONVECTION EXTENDING FROM NEAR DECORAH TO FORT DODGE TO NEAR OMAHA. IN ADDITION...OTHER THUNDERSTORM OUTFLOW BOUNDARIES WERE PRESENT ACROSS SOUTHWEST IOWA. VERY UNSTABLE AIR WAS PRESENT OVER IOWA THIS MORNING WITH LIFTED INDICES OF MINUS 6 TO MINUS 8. THUNDERSTORMS WILL CONTINUE TO LOCALLY EXCEED SEVERE LIMITS THROUGH 9 AM. THE PRIMARY THREAT WILL BE DAMAGING WINDS AND HAIL UP TO 1 INCH IN DIAMETER. AFTER THIS MORNINGS THUNDERSTORMS DISSIPATE...THE OUTFLOW BOUNDARIES AND THE FRONTAL BOUNDARY WILL ACT TO FOCUS THUNDERSTORM DEVELOPMENT LATE THIS AFTERNOON. TEMPERATURES SHOULD CLIMB INTO THE UPPER 80S AND LOWER 90S THIS AFTERNOON ONCE THE CLOUDS FROM THIS MORNINGS ACTION DIMINISHES. THIS COMBINED WITH HIGH DEWPOINTS WILL ALLOW THE AIRMASS TO BECOME VERY UNSTABLE. A STRONGER WIND FIELD IS FORECAST OVER IOWA THIS AFTERNOON SUGGESTING ORGANIZED MULTICELL AND EVEN ISOLATED SUPERCELL THUNDERSTORMS. PRECAUTIONS -- EMERGENCY MANAGERS SHOULD BE READY TO DEPLOY SPOTTERS THIS MORNING OVER NORTHERN IOWA AND ACROSS MOST OF IOWA THIS AFTERNOON. REMEMBER TO PASS ALONG ALL REPORTS OF SEVERE WEATHER TO COUNTY DISPATCHERS AND THE NATIONAL WEATHER SERVICE. JOHNSON
Special weather statement, Jun 20, 7:01 AM CDT, 24 minutes before
IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086- 092>097-201800- CENTRAL IOWA THUNDERSTORM OUTLOOK NATIONAL WEATHER SERVICE DES MOINES IA 645 AM CDT FRI JUN 20 1997 HAZARD -- ISOLATED SEVERE THUNDERSTORMS NORTHERN IOWA THIS MORNING CAPABLE OF LARGE HAIL AND DAMAGING WINDS. A RISK OF SEVERE STORMS ACROSS MOST OF THE AREA NORTH OF A LAMONI TO OTTUMWA LINE THIS AFTERNOON. TIMING AND AREA OF CONCERN -- THROUGH 1000 AM FOR NORTHERN IOWA THIS MORNING. AFTER 3 PM FOR THE AFTERNOON THUNDERSTORMS. METEOROLOGICAL COMMENTS -- A COLD FRONT WAS FORCED SOUTH THIS MORNING DUE TO STRONG CONVECTION EXTENDING FROM NEAR DECORAH TO FORT DODGE TO NEAR OMAHA. IN ADDITION...OTHER THUNDERSTORM OUTFLOW BOUNDARIES WERE PRESENT ACROSS SOUTHWEST IOWA. VERY UNSTABLE AIR WAS PRESENT OVER IOWA THIS MORNING WITH LIFTED INDICES OF MINUS 6 TO MINUS 8. THUNDERSTORMS WILL CONTINUE TO LOCALLY EXCEED SEVERE LIMITS THROUGH 9 AM. THE PRIMARY THREAT WILL BE DAMAGING WINDS AND HAIL UP TO 1 INCH IN DIAMETER. AFTER THIS MORNINGS THUNDERSTORMS DISSIPATE...THE OUTFLOW BOUNDARIES AND THE FRONTAL BOUNDARY WILL ACT TO FOCUS THUNDERSTORM DEVELOPMENT LATE THIS AFTERNOON. TEMPERATURES SHOULD CLIMB INTO THE UPPER 80S AND LOWER 90S THIS AFTERNOON ONCE THE CLOUDS FROM THIS MORNINGS ACTION DIMINISHES. THIS COMBINED WITH HIGH DEWPOINTS WILL ALLOW THE AIRMASS TO BECOME VERY UNSTABLE. A STRONGER WIND FIELD IS FORECAST OVER IOWA THIS AFTERNOON SUGGESTING ORGANIZED MULTICELL AND EVEN ISOLATED SUPERCELL THUNDERSTORMS. PRECAUTIONS -- EMERGENCY MANAGERS SHOULD BE READY TO DEPLOY SPOTTERS THIS MORNING OVER NORTHERN IOWA AND ACROSS MOST OF IOWA THIS AFTERNOON. REMEMBER TO PASS ALONG ALL REPORTS OF SEVERE WEATHER TO COUNTY DISPATCHERS AND THE NATIONAL WEATHER SERVICE. JOHNSON
The office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 20, 12:48 AM CDT | Severe Thunderstorm Warning | DMX | Cass | 32 min |
| Jun 20, 1:20 AM CDT | Severe Thunderstorm Warning | DMX | Adair, Cass | 50 min |
| Jun 20, 5:02 AM CDT | Severe Thunderstorm Warning | DMX | Webster | 33 min |
| Jun 20, 5:17 AM CDT | Severe Thunderstorm Warning | DMX | Hamilton, Wright | 33 min |
| Jun 20, 5:48 AM CDT | Severe Thunderstorm Warning | DMX | Franklin, Hardin | 32 min |
| Jun 20, 6:09 AM CDT | Severe Thunderstorm Warning | DMX | Butler, Grundy | 36 min |
| Jun 20, 6:45 AM CDT | Severe Thunderstorm Warning | DMX | Black Hawk | 45 min |
| Jun 20, 4:39 PM CDT | Severe Thunderstorm Warning | DMX | Warren | 31 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.