Alert archive / Nebraska / Tornado Warnings in 2002

Tornado Warning 20, NWS Omaha, NE

August 16, 2002Cedar County, Knox County, Nebraska

NWS Omaha, NE issued this tornado warning at Aug 16, 2002, 7:57 PM CDT for Cedar County, Knox County, Nebraska. It was in force for 33 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
Aug 16, 2002, 7:57 PM CDT (00:57 UTC)
Expired
Aug 16, 2002, 8:30 PM CDT
In force
33 min
Issued by
NWS Omaha, NE
Area
Counties, with a storm outline in the text

Counties Cedar County, NE, Knox County, NE

The radar

The Sioux Falls radar (KFSD), 128 km from the middle of the area, began a volume at 00:56 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

TimeReportWhereRemark
Aug 16, 8:06 PM CDTHail 0.88Crofton, NEReported near Gavins Point Dam.
Aug 16, 8:10 PM CDTHail 1.75St Helena, NEHail up to golfball size was reported near St Helena for a 15 minute period.

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 00:00Z, 1.0 hours before the alert went out and 175 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 2002-08-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3070 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Omaha, NE at 00:00Z on 2002-08-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 229 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
3070 J/kg
Mixed-layer CIN
-50 J/kg
Mixed-layer LCL
1356 m above ground
0-6 km bulk shear
55 kt
0-1 km storm-relative helicity
229 m²/s²
0-3 km storm-relative helicity
597 m²/s²
Significant tornado parameter
3.9
Supercell composite
18.4

Open this sounding in Storm Lab

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 16, 7:25 PM CDTTornado WarningOAXKnox35 min
Aug 16, 8:31 PM CDTSevere Thunderstorm WarningOAXCedar29 min
Aug 17, 12:02 AM CDTSevere Thunderstorm WarningOAXAntelope28 min
Aug 17, 12:17 AM CDTSevere Thunderstorm WarningOAXPierce, Wayne43 min
Aug 17, 12:30 AM CDTSevere Thunderstorm WarningOAXAntelope, Boone, Madison60 min
Aug 17, 12:39 AM CDTSevere Thunderstorm WarningOAXCedar36 min
Aug 17, 1:04 AM CDTSevere Thunderstorm WarningOAXThurston, Wayne41 min
Aug 17, 1:16 AM CDTSevere Thunderstorm WarningOAXCuming, Stanton44 min
Aug 17, 1:42 AM CDTSevere Thunderstorm WarningOAXColfax, Dodge48 min
Aug 17, 1:53 AM CDTSevere Thunderstorm WarningOAXBurt22 min
Aug 17, 2:55 AM CDTSevere Thunderstorm WarningOAXCass, Lancaster, Otoe, Sarpy35 min
Aug 17, 3:03 AM CDTSevere Thunderstorm WarningOAXGage, Jefferson, Saline42 min
Aug 17, 3:13 AM CDTSevere Thunderstorm WarningOAXJohnson, Pawnee32 min
Aug 17, 3:27 AM CDTSevere Thunderstorm WarningOAXNemaha, Richardson33 min
Aug 17, 3:51 AM CDTSevere Thunderstorm WarningOAXGage, Jefferson, Johnson, Pawnee24 min

Nearby

Tornado Warnings in Nebraska, 2002Every tornado warning in 2002Tornadoes in 2002

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.