Alert archive / Iowa / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 21, NWS Omaha, NE

May 16, 1997Pottawattamie County, Iowa

NWS Omaha, NE issued this severe thunderstorm warning at May 16, 1997, 5:24 PM CDT for Pottawattamie County, Iowa. It was in force for 31 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
May 16, 1997, 5:24 PM CDT (22:24 UTC)
Expired
May 16, 1997, 5:55 PM CDT
In force
31 min
Issued by
NWS Omaha, NE
Area
Whole counties

County Pottawattamie County, IA

The radar

The Omaha radar (KOAX), 69 km from the middle of the area, began a volume at 22:28 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.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
May 16, 5:00 PM CDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 10.4 hours before the alert went out and 69 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, Omaha, NE at 12:00Z on 1997-05-16Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Omaha, NE at 12:00Z on 1997-05-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 121 square meters per square second.193958Sfc1 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
2709 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
121 m²/s²
0-3 km storm-relative helicity
271 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.

147 
WUUS1 KOMA 162224 RRA
SVROMA
IAC155-162255-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
524 PM CDT FRI MAY 16 1997

* SEVERE THUNDERSTORM WARNING FOR
  POTTAWATTAMIE COUNTY - IN SOUTHWESTERN IOWA

* UNTIL 555 PM CDT
 
* SOME LOCATIONS AFFECTED
  HANCOCK                      BY AROUND 530 PM CDT
  OAKLAND                      BY AROUND 530 PM CDT
  CARSON                       BY AROUND 535 PM CDT
  MACEDONIA                    BY AROUND 535 PM CDT

* AT 523 PM CDT...A SEVERE THUNDERSTORM WAS INDICATED BY DOPPLER
  RADAR 20 MILES EAST NORTHEAST OF DOWNTOWN OMAHA OR 9 MILES WEST
  NORTHWEST OF OAKLAND MOVING SOUTHEAST AT 40 MPH.
 
PEOPLE IN THE WARNED AREA SHOULD GET INTO A REINFORCED SHELTER AND
PREPARE FOR DAMAGING WINDS...LARGE HAIL...VERY HEAVY RAIN...AND
DANGEROUS LIGHTNING.

GW

The office that day

Everything else NWS Omaha, NE issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 16, 5:53 PM CDTSevere Thunderstorm WarningOAXMills, Montgomery, Pottawattamie47 min
May 16, 6:27 PM CDTSevere Thunderstorm WarningOAXFremont, Page63 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.