Alert archive / Iowa / Severe Thunderstorm Warnings in 1997
Severe Thunderstorm Warning 43, NWS Des Moines, IA
NWS Des Moines, IA issued this severe thunderstorm warning at Jun 20, 1997, 5:48 AM CDT for Franklin County, Hardin County, Iowa. It was in force for 32 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, 5:48 AM CDT (10:48 UTC)
- Expired
- Jun 20, 1997, 6:20 AM CDT
- In force
- 32 min
- Issued by
- NWS Des Moines, IA
- Area
- Whole counties
Counties Franklin County, IA, Hardin County, IA
The radar
The Des Moines radar (KDMX), 100 km from the middle of the area, began a volume at 10:47 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, 6:07 AM CDT | Thunderstorm Wind 70 | Eldora, 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 00:00Z, 10.8 hours before the alert went out and 250 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
- 1838 J/kg
- Mixed-layer CIN
- -63 J/kg
- Mixed-layer LCL
- 1254 m above ground
- 0-6 km bulk shear
- 26 kt
- 0-1 km storm-relative helicity
- 85 m²/s²
- 0-3 km storm-relative helicity
- 248 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 4.1
The text
As transmitted, in the capitals the NWS used until 2016.
000
TTAA00 KDSM 201046 RRA
SVRDSM
IAC069-083-201120-
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
548 AM CDT FRI JUN 20 1997
* SEVERE THUNDERSTORM WARNING FOR
FRANKLIN COUNTY - NORTH CENTRAL IOWA
NORTHERN HARDIN COUNTY - CENTRAL IOWA
* UNTIL 620 AM CDT
* SOME AREAS AFFECTED
IOWA FALLS
ALDEN
HAMPTON
BRADFORD
* AT 645 PM CDT RADAR INDICATED A SEVERE THUNDERSTORM ALONG I35 65
MILES NORTfH OF DES MOINES MOVING EAST AT 40 MPH.
* THE STORM WILL BE THROUGH HAMPTON AND IOWA FALLS BY 605 AM.
THIS IS A DANGEROUS STORM. DO NOT GO OUTDOORS.
JOHNSONWhat 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, Jun 20, 12:15 AM CDT, 5 hours 33 minutes before
IAZ004>007-015>017-023>028-033>039-044>050-057>062-201200- CENTRAL IOWA THUNDERSTORM OUTLOOK NATIONAL WEATHER SERVICE DES MOINES IA 1215 AM CDT FRI JUN 20 1997 ...SEVERE THUNDERSTORM WATCH ISSUED FOR THE NORTHWEST QUARTER OF IOWA UNTIL 200 AM... HAZARD--SCATTERED SEVERE THUNDERSTORMS CAPABLE OF PRODUCING WIND GUSTS UP TO 80 MPH...HAIL TO 1 INCH IN DIAMETER AND LOCALIZED RAINFALL AMOUNTS OF UP TO 3 INCHES. AREA OF CONCERN--NORTHWEST OF A WATERLOO-CHARITON LINE...WITH THE HIGHEST THREAT NORTH OF INTERSTATE 80 AND WEST OF INTERSTATE 35. TIMING DETAILS--SCATTERED THUNDERSTORMS WILL CONTINUE TO MOVE SOUTHEAST INTO CENTRAL IOWA AND EXPAND IN AREAL COVERAGE THROUGH 500 AM. METEOROLOGICAL COMMENTS--SUPERCELL THUNDERSTORMS THAT MOVED INTO FAR NORTHWEST IOWA FROM NORTHEAST NEBRASKA DECREASED IN INTENSITY AS THEY MOVED INTO A SOMEWHAT MORE STABLE ENVIRONMENT EARLY THIS MORNING. HOWEVER...STORMS SHOULD INTENSIFY AS THEY MOVE FURTHER EAST INTO IOWA...SOUTH OF A WARM FRONTAL BOUNDARY THAT REMAINED DRAPED ACROSS NORTHERN IOWA. DEW POINTS IN THIS AREA WERE IN THE UPPER 60S TO LOWER 70S AND NUMEROUS OUTFLOW BOUNDARIES WERE IN PLACE TO ACT AS A LIFTING MECHANISM FOR ANY DEVELOPING/INTENSIFYING STORMS. LIFTED INDICES IN CENTRAL IOWA REMAINED AROUND -8. A SOUTHERLY LOW LEVEL JET AT 30 KTS WILL PROVIDE INFLOW TO THE STORMS. PRECAUTIONS--SPOTTERS SHOULD REMAIN ALERT TO RAPIDLY DEVELOPING OR INTENSIFYING STORMS ESPECIALLY NORTHWEST OF DES MOINES. THESE STORMS HAVE A HISTORY OF PRODUCING DAMAGING STRAIGHT LINE WINDS. AROUND THREE INCHES OF RAIN IS NEEDED TO CAUSE FLASH FLOODING IN MANY AREAS...SO THE HEAVY RAIN OVERNIGHT COULD CAUSE SOME RUNOFF PROBLEMS. STARK
Special weather statement, Jun 20, 12:18 AM CDT, 5 hours 30 minutes before
IAZ004>007-015>017-023>028-033>039-044>050-057>062-201200- CENTRAL IOWA THUNDERSTORM OUTLOOK NATIONAL WEATHER SERVICE DES MOINES IA 1215 AM CDT FRI JUN 20 1997 ...SEVERE THUNDERSTORM WATCH ISSUED FOR THE NORTHWEST QUARTER OF IOWA UNTIL 200 AM... HAZARD--SCATTERED SEVERE THUNDERSTORMS CAPABLE OF PRODUCING WIND GUSTS UP TO 80 MPH...HAIL TO 1 INCH IN DIAMETER AND LOCALIZED RAINFALL AMOUNTS OF UP TO 3 INCHES. AREA OF CONCERN--NORTHWEST OF A WATERLOO-CHARITON LINE...WITH THE HIGHEST THREAT NORTH OF INTERSTATE 80 AND WEST OF INTERSTATE 35. TIMING DETAILS--SCATTERED THUNDERSTORMS WILL CONTINUE TO MOVE SOUTHEAST INTO CENTRAL IOWA AND EXPAND IN AREAL COVERAGE THROUGH 500 AM. METEOROLOGICAL COMMENTS--SUPERCELL THUNDERSTORMS THAT MOVED INTO FAR NORTHWEST IOWA FROM NORTHEAST NEBRASKA DECREASED IN INTENSITY AS THEY MOVED INTO A SOMEWHAT MORE STABLE ENVIRONMENT EARLY THIS MORNING. HOWEVER...STORMS SHOULD INTENSIFY AS THEY MOVE FURTHER EAST INTO IOWA...SOUTH OF A WARM FRONTAL BOUNDARY THAT REMAINED DRAPED ACROSS NORTHERN IOWA. DEW POINTS IN THIS AREA WERE IN THE UPPER 60S TO LOWER 70S AND NUMEROUS OUTFLOW BOUNDARIES WERE IN PLACE TO ACT AS A LIFTING MECHANISM FOR ANY DEVELOPING/INTENSIFYING STORMS. LIFTED INDICES IN CENTRAL IOWA REMAINED AROUND -8. A SOUTHERLY LOW LEVEL JET AT 30 KTS WILL PROVIDE INFLOW TO THE STORMS. PRECAUTIONS--SPOTTERS SHOULD REMAIN ALERT TO RAPIDLY DEVELOPING OR INTENSIFYING STORMS ESPECIALLY NORTHWEST OF DES MOINES. THESE STORMS HAVE A HISTORY OF PRODUCING DAMAGING STRAIGHT LINE WINDS. AROUND THREE INCHES OF RAIN IS NEEDED TO CAUSE FLASH FLOODING IN MANY AREAS...SO THE HEAVY RAIN OVERNIGHT COULD CAUSE SOME RUNOFF PROBLEMS. STARK
Local storm report, Jun 20, 2:05 AM CDT, 3 hours 43 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, 3 hours 41 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, 3 hours 20 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
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, 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, 7:25 AM CDT | Severe Thunderstorm Warning | DMX | Butler | 35 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.