Alert archive / Nebraska / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 101, NWS Omaha, NE

May 20, 1998Cass County, Otoe County, Nebraska; Mills County, Iowa

NWS Omaha, NE issued this severe thunderstorm warning at May 20, 1998, 3:20 AM CDT for Cass County, Otoe County, Nebraska; Mills County, Iowa. It was in force for 50 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
May 20, 1998, 3:20 AM CDT (08:20 UTC)
Expired
May 20, 1998, 4:10 AM CDT
In force
50 min
Issued by
NWS Omaha, NE
Area
Whole counties

Counties Mills County, IA, Cass County, NE, Otoe County, NE

What was reported inside it

TimeReportWhereRemark
May 20, 4:05 AM CDTHail 1Nebraska City, NE

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.

IssuedProductOfficeLasted
May 20, 1:45 AM CDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 8.3 hours before the alert went out and 61 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 00:00Z on 1998-05-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2454 joules per kilogram.LCLLFCEL10008507005003002001001 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 00:00Z on 1998-05-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 21 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
2454 J/kg
Mixed-layer CIN
-8 J/kg
Mixed-layer LCL
1962 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
21 m²/s²
0-3 km storm-relative helicity
64 m²/s²
Significant tornado parameter
0.0
Supercell composite
3.4

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

The office that day

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

IssuedProductOfficeCountiesLasted
May 19, 11:38 PM CDTSevere Thunderstorm WarningOAXAntelope62 min
May 20, 12:14 AM CDTSevere Thunderstorm WarningOAXBoone61 min
May 20, 12:38 AM CDTSevere Thunderstorm WarningOAXMadison, Platte62 min
May 20, 1:30 AM CDTSevere Thunderstorm WarningOAXButler, Colfax60 min
May 20, 1:38 AM CDTSevere Thunderstorm WarningOAXPlatte32 min
May 20, 1:47 AM CDTSevere Thunderstorm WarningOAXSeward63 min
May 20, 1:55 AM CDTSevere Thunderstorm WarningOAXDodge, Saunders60 min
May 20, 2:00 AM CDTSevere Thunderstorm WarningOAXLancaster, Saline60 min
May 20, 2:30 AM CDTSevere Thunderstorm WarningOAXCass, Gage, Otoe60 min
May 20, 2:30 AM CDTSevere Thunderstorm WarningOAXDouglas, Sarpy60 min
May 20, 2:30 AM CDTSevere Thunderstorm WarningOAXWashington60 min
May 20, 4:08 AM CDTSevere Thunderstorm WarningOAXNemaha32 min
May 20, 3:11 AM CDTSevere Thunderstorm WarningOAXHarrison49 min
May 20, 3:20 AM CDTSevere Thunderstorm WarningOAXPottawattamie50 min
May 20, 3:41 AM CDTSevere Thunderstorm WarningOAXShelby64 min

Nearby

Severe Thunderstorm Warnings in Nebraska, 1998Severe Thunderstorm Warnings in Iowa, 1998Every severe thunderstorm warning in 1998

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.