Alert archive / Nebraska / Tornado Watches in 1998

Tornado Watch 387

May 21, 1998Logan County, Phillips County, Sedgwick County, Colorado; 7 counties in Kansas; 36 counties in Nebraska

The Storm Prediction Center issued this tornado watch at May 21, 1998, 2:15 PM MDT for Logan County, Phillips County, Sedgwick County, Colorado; 7 counties in Kansas; 36 counties in Nebraska. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
May 21, 1998, 2:15 PM MDT (20:15 UTC)
Expired
May 21, 1998, 8:00 PM MDT
In force
6 hr
Issued by
the Storm Prediction Center
All 46 counties

Logan County, CO, Phillips County, CO, Sedgwick County, CO, Decatur County, KS, Graham County, KS, Norton County, KS, Osborne County, KS, Phillips County, KS, Rooks County, KS, Smith County, KS, Arthur County, NE, Banner County, NE, Box Butte County, NE, Buffalo County, NE, Chase County, NE, Cheyenne County, NE, Custer County, NE, Dawes County, NE, Dawson County, NE, Deuel County, NE, Dundy County, NE, Franklin County, NE, Frontier County, NE, Furnas County, NE, Garden County, NE, Gosper County, NE, Grant County, NE, Harlan County, NE, Hayes County, NE, Hitchcock County, NE, Hooker County, NE, Kearney County, NE, Keith County, NE, Kimball County, NE, Lincoln County, NE, Logan County, NE, McPherson County, NE, Morrill County, NE, Perkins County, NE, Phelps County, NE, Red Willow County, NE, Scotts Bluff County, NE, Sheridan County, NE, Sherman County, NE, Sioux County, NE, Thomas County, NE

The radar

The North Platte radar (KLNX), 116 km from the middle of the area, began a volume at 20:17 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.

Warnings issued inside it

28 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
May 21, 2:57 PM MDTSevere Thunderstorm WarningLBFHooker, McPherson, Thomas63 min
May 21, 3:03 PM MDTSevere Thunderstorm WarningLBFKeith, Lincoln62 min
May 21, 4:51 PM MDTSevere Thunderstorm WarningBOULogan, Weld39 min
May 21, 5:35 PM MDTSevere Thunderstorm WarningBOULogan35 min
May 21, 5:37 PM MDTSevere Thunderstorm WarningGLDRed Willow33 min
May 21, 5:38 PM MDTSevere Thunderstorm WarningLBFFrontier62 min
May 21, 5:41 PM MDTTornado WarningBOUPhillips, Sedgwick39 min
May 21, 5:47 PM MDTTornado WarningBOUPhillips, Sedgwick33 min
May 21, 5:57 PM MDTSevere Thunderstorm WarningGIDGosper, Phelps33 min
May 21, 6:01 PM MDTTornado WarningLBFFrontier34 min
May 21, 6:11 PM MDTSevere Thunderstorm WarningCYSCheyenne49 min
May 21, 6:13 PM MDTTornado WarningBOUPhillips, Sedgwick22 min
May 21, 6:13 PM MDTTornado WarningLBFPerkins32 min
May 21, 6:15 PM MDTSevere Thunderstorm WarningBOULogan45 min
May 21, 6:19 PM MDTSevere Thunderstorm WarningLBFLincoln66 min
May 21, 6:22 PM MDTTornado WarningGIDPhelps38 min
May 21, 6:27 PM MDTSevere Thunderstorm WarningGIDGosper33 min
May 21, 6:31 PM MDTSevere Thunderstorm WarningGLDRed Willow29 min
May 21, 6:32 PM MDTTornado WarningGIDGosper28 min
May 21, 6:35 PM MDTTornado WarningGLDRed Willow35 min
May 21, 6:38 PM MDTTornado WarningLBFFrontier32 min
May 21, 6:40 PM MDTTornado WarningGIDKearney50 min
May 21, 6:44 PM MDTSevere Thunderstorm WarningLBFChase, Perkins66 min
May 21, 6:48 PM MDTTornado WarningLBFChase, Perkins62 min
May 21, 6:59 PM MDTTornado WarningGIDFurnas, Gosper, Phelps31 min
May 21, 7:29 PM MDTTornado WarningLBFHayes66 min
May 21, 7:30 PM MDTTornado WarningGIDKearney, Phelps30 min
May 21, 7:59 PM MDTTornado WarningLBFHayes66 min

The nearest sounding before it

N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 8.3 hours before the alert went out and 104 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, N. Platte/Lee Bi, NE at 12:00Z on 1998-05-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 379 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, N. Platte/Lee Bi, NE at 12:00Z on 1998-05-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -32 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
379 J/kg
Mixed-layer CIN
-274 J/kg
Mixed-layer LCL
943 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
-32 m²/s²
0-3 km storm-relative helicity
128 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

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.

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 21, 8:45 AM MDTSevere Thunderstorm WatchSPCBrown, Doniphan, Marshall, Nemaha, Republic, Washington5 hr
May 20, 10:30 PM MDTSevere Thunderstorm WatchSPCAntelope, Arthur, Blaine, Boone, Brown, Cedar and 18 more6 hr

Nearby

Tornado Watches in Nebraska, 1998Tornado Watches in Kansas, 1998Tornado Watches in Colorado, 1998Every tornado watch 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.