Alert archive / Iowa / Severe Thunderstorm Warnings in 1997
Severe Thunderstorm Warning 97, NWS Omaha, NE
NWS Omaha, NE issued this severe thunderstorm warning at Jul 13, 1997, 5:55 PM CDT for Mills County, Iowa. It was in force for 45 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
- Jul 13, 1997, 5:55 PM CDT (22:55 UTC)
- Expired
- Jul 13, 1997, 6:40 PM CDT
- In force
- 45 min
- Issued by
- NWS Omaha, NE
- Area
- Whole counties
County Mills County, IA
The radar
The Omaha radar (KOAX), 70 km from the middle of the area, began a volume at 22:54 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 |
|---|---|---|---|
| Jul 13, 6:20 PM CDT | Hail 1.75 | Malvern, 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
Omaha, NE (KOAX), launched 12:00Z, 10.9 hours before the alert went out and 70 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
- 2893 J/kg
- Mixed-layer CIN
- -148 J/kg
- Mixed-layer LCL
- 1200 m above ground
- 0-6 km bulk shear
- 26 kt
- 0-1 km storm-relative helicity
- 184 m²/s²
- 0-3 km storm-relative helicity
- 152 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.
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, Jul 13, 5:55 PM CDT, 0 minutes before
NEZ015-018-032-033-IAZ043-140300- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE OMAHA/VALLEY NE 555 PM CDT SUN JUL 13 1997 THE PORTION OF SEVERE THUNDERSTORM WATCH IN NORTHEAST NEBRASKA HAS BEEN CANCELLED. THE WATCH IS NO LONGER IN EFFECT FOR CUMING...STANTON ...THURSTON...OR WAYNE COUNTIES IN NEBRASKA...OR MONONA COUNTY IOWA. OTHER THUNDERSTORMS ARE DEVELOPING RAPIDLY IN SOUTHWEST IOWA AND COULD EXTEND INTO THE SOUTHEAST CORNER OF NEBRASKA. SEVERE WEATHER WILL BE POSSIBLE WITH THESE STORMS. POLLACK
The office that day
Everything else NWS Omaha, NE issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 13, 4:25 AM CDT | Severe Thunderstorm Warning | OAX | Cedar, Knox | 50 min |
| Jul 12, 8:19 PM CDT | Severe Thunderstorm Warning | OAX | Monona | 46 min |
| Jul 13, 6:47 PM CDT | Tornado Warning | OAX | Mills, Montgomery | 33 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.