Alert archive / Iowa / Severe Thunderstorm Warnings in 1997
Severe Thunderstorm Warning 24, NWS Des Moines, IA
NWS Des Moines, IA issued this severe thunderstorm warning at May 16, 1997, 7:23 PM CDT for Clarke County, Iowa. It was in force for 47 min. 2 reports 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 16, 1997, 7:23 PM CDT (00:23 UTC)
- Expired
- May 16, 1997, 8:10 PM CDT
- In force
- 47 min
- Issued by
- NWS Des Moines, IA
- Area
- Whole counties
County Clarke County, IA
The radar
The Des Moines radar (KDMX), 78 km from the middle of the area, began a volume at 00:25 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 |
|---|---|---|---|
| May 16, 7:27 PM CDT | Hail 0.75 | Murray, IA | |
| May 16, 7:33 PM CDT | Hail 1.75 | Osceola, 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 |
|---|---|---|---|
| May 16, 5:00 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
The nearest sounding before it
Omaha, NE (KOAX), launched 00:00Z, 0.4 hours before the alert went out and 219 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
- 102 J/kg
- Mixed-layer CIN
- -79 J/kg
- Mixed-layer LCL
- 3249 m above ground
- 0-6 km bulk shear
- 36 kt
- 0-1 km storm-relative helicity
- 79 m²/s²
- 0-3 km storm-relative helicity
- 124 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
The text
As transmitted, in the capitals the NWS used until 2016.
800
WUUS1 KDSM 170024 RRA
SVRDSM
IAC039-170110-
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
723 PM CDT FRI MAY 16 1997
* SEVERE THUNDERSTORM WARNING FOR
CLARKE COUNTY - SOUTH CENTRAL IOWA
* UNTIL 810 PM CDT
* SOME AREAS AFFECTED
OSCEOLA
MURRAY
WOODBURN
* AT AT 720 PM CDT THE PUBLIC REPORTED A SEVERE THUNDERSTORM NEAR
MURRAY OR 40 MILES SOUTH OF DES MOINES MOVING SOUTHEAST AT 35 MPH.
* THE STORM WILL BE NEAR OSCEOLA AT 740 PM.
THIS IS A DANGEROUS STORM. DO NOT GO OUTDOORS.
STARKWhat 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 16, 2:20 PM CDT, 5 hours 3 minutes before
IAZ004-005-015-023-024-033>035-044>046-057-058-070-071-081>086- 092>097-170115- CENTRAL IOWA THUNDERSTORM OUTLOOK NATIONAL WEATHER SERVICE DES MOINES IA 222 PM CDT FRI MAY 16 1997 HAZARD--WIDELY SCATTERED THUNDERSTORMS. A FEW COULD PRODUCE LARGE HAIL AND WIND GUSTS OVER 55 MPH. AREAS OF CONCERN--WESTERN AND SOUTHERN IOWA...SOUTH AND WEST OF AN ALGONA...TO ADAIR...TO CHARITON LINE. TIMING DETAILS--DURING THE LATE AFTERNOON AND EARLY EVENING HOURS STARTING AFTER 300 PM AND LASTING UNTIL AROUND 800 PM. METEOROLOGICAL COMMENTS--BREEZY SOUTHWEST WINDS WERE WARMING UP TEMPERATURES ACROSS IOWA BUT WERE ALSO INCREASING MOISTURE LEVELS...ESPECIALLY OVER WESTERN PORTIONS OF THE STATE. BY LATE THIS AFTERNOON LOW LEVEL MOISTURE MAY INCREASE ENOUGH TO PRODUCE WEAK INSTABILITY AND ALLOW WIDELY SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP ACROSS WESTERN AND SOUTHWEST IOWA. EVEN THOUGH THE MOISTURE WILL INCREASE SOME...IT WILL STILL BE RELATIVELY DRY IN THE LOW LEVELS OF THE ATMOSPHERE SO GUSTY WINDS WOULD BE THE PRIMARY THREAT. WIDESPREAD SHOWERS AND STORMS ARE NOT EXPECTED HOWEVER...SO MOST SPOTS SHOULD NOT BE AFFECTED. PRECAUTIONS--NO ACTIONS NEED TO BE TAKEN AT THIS TIME. HOWEVER PEOPLE WITH OUTDOOR ACTIVITIES PLANNED LATE THIS AFTERNOON AND EARLY THIS EVENING SHOULD MONITOR THE LATEST SHORT TERM FORECASTS AND OUTLOOKS FOR UPDATED INFORMATION. SMALL
Special weather statement, May 16, 2:22 PM CDT, 5 hours 1 minute before
IAZ004-005-015-023-024-033>035-044>046-057-058-070-071-081>086- 092>097-170115- CENTRAL IOWA THUNDERSTORM OUTLOOK NATIONAL WEATHER SERVICE DES MOINES IA 222 PM CDT FRI MAY 16 1997 HAZARD--WIDELY SCATTERED THUNDERSTORMS. A FEW COULD PRODUCE LARGE HAIL AND WIND GUSTS OVER 55 MPH. AREAS OF CONCERN--WESTERN AND SOUTHERN IOWA...SOUTH AND WEST OF AN ALGONA...TO ADAIR...TO CHARITON LINE. TIMING DETAILS--DURING THE LATE AFTERNOON AND EARLY EVENING HOURS STARTING AFTER 300 PM AND LASTING UNTIL AROUND 800 PM. METEOROLOGICAL COMMENTS--BREEZY SOUTHWEST WINDS WERE WARMING UP TEMPERATURES ACROSS IOWA BUT WERE ALSO INCREASING MOISTURE LEVELS...ESPECIALLY OVER WESTERN PORTIONS OF THE STATE. BY LATE THIS AFTERNOON LOW LEVEL MOISTURE MAY INCREASE ENOUGH TO PRODUCE WEAK INSTABILITY AND ALLOW WIDELY SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP ACROSS WESTERN AND SOUTHWEST IOWA. EVEN THOUGH THE MOISTURE WILL INCREASE SOME...IT WILL STILL BE RELATIVELY DRY IN THE LOW LEVELS OF THE ATMOSPHERE SO GUSTY WINDS WOULD BE THE PRIMARY THREAT. WIDESPREAD SHOWERS AND STORMS ARE NOT EXPECTED HOWEVER...SO MOST SPOTS SHOULD NOT BE AFFECTED. PRECAUTIONS--NO ACTIONS NEED TO BE TAKEN AT THIS TIME. HOWEVER PEOPLE WITH OUTDOOR ACTIVITIES PLANNED LATE THIS AFTERNOON AND EARLY THIS EVENING SHOULD MONITOR THE LATEST SHORT TERM FORECASTS AND OUTLOOKS FOR UPDATED INFORMATION. SMALL
Special weather statement, May 16, 6:35 PM CDT, 48 minutes before
IAZ034>039-044>049-057-058-170100 SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DES MOINES IA 635 PM CDT FRI MAY 16 1997 ...PARTIAL CLEARANCE OF SEVERE THUNDERSTORM WATCH NUMBER 287... THE FOLLOWING COUNTIES HAVE BEEN CLEARED FROM SEVERE THUNDERSTORM WATCH NUMBR 287. CALHOUN - WEBSTER - HAMILTON - HARDIN - GRUNDY - BLACK HAWK CRAWFORD - CARROLL - GREENE - BOONE - STORY - MARSHALL - AUDUBON AND GUTHRIE. THE STRONG TO SEVERE THUNDERSTORMS HAVE MOVED SOUTHEAST OF THE AREA. THOUGH SCATTERED SHOWERS WILL PASS THROUGH THE AREA DURING THE NEXT TWO HOURS...SEVERE STORMS ARE NOT EXPECTED.
Special weather statement, May 16, 6:36 PM CDT, 47 minutes before
IAZ034>039-044>049-057-058-170100 SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DES MOINES IA 635 PM CDT FRI MAY 16 1997 ...PARTIAL CLEARANCE OF SEVERE THUNDERSTORM WATCH NUMBER 287... THE FOLLOWING COUNTIES HAVE BEEN CLEARED FROM SEVERE THUNDERSTORM WATCH NUMBR 287. CALHOUN - WEBSTER - HAMILTON - HARDIN - GRUNDY - BLACK HAWK CRAWFORD - CARROLL - GREENE - BOONE - STORY - MARSHALL - AUDUBON AND GUTHRIE. THE STRONG TO SEVERE THUNDERSTORvMS HAVE MOVED SOUTHEAST OF THE AREA. THOUGH SCATTERED SHOWERS WILL PASS THROUGH THE AREA DURING THE NEXT TWO HOURS...SEVERE STORMS ARE NOT EXPECTED.
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.