Alert archive / Nebraska / Tornado Watches in 1999

Tornado Watch 484

June 27, 1999Phillips County, Sedgwick County, Colorado; 41 counties in Nebraska

The Storm Prediction Center issued this tornado watch at Jun 27, 1999, 7:15 PM MDT for Phillips County, Sedgwick County, Colorado; 41 counties in Nebraska. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
Jun 27, 1999, 7:15 PM MDT (01:15 UTC)
Expired
Jun 27, 1999, 11:00 PM MDT
In force
4 hr
Issued by
the Storm Prediction Center
All 43 counties

Phillips County, CO, Sedgwick County, CO, Adams County, NE, Arthur County, NE, Boone County, NE, Buffalo County, NE, Chase County, NE, Clay County, NE, Custer County, NE, Dawson County, NE, Deuel County, NE, Dundy County, NE, Fillmore County, NE, Franklin County, NE, Frontier County, NE, Furnas County, NE, Garden County, NE, Gosper County, NE, Greeley County, NE, Hall County, NE, Hamilton County, NE, Harlan County, NE, Hayes County, NE, Hitchcock County, NE, Howard County, NE, Kearney County, NE, Keith County, NE, Lincoln County, NE, Logan County, NE, McPherson County, NE, Merrick County, NE, Nance County, NE, Nuckolls County, NE, Perkins County, NE, Phelps County, NE, Platte County, NE, Polk County, NE, Red Willow County, NE, Sherman County, NE, Thayer County, NE, Valley County, NE, Webster County, NE, York County, NE

The radar

The North Platte radar (KLNX), 100 km from the middle of the area, began a volume at 01:17 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

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

IssuedProductOfficeCountiesLasted
Jun 27, 7:37 PM MDTTornado WarningLBFGarden, Keith63 min
Jun 27, 7:55 PM MDTTornado WarningLBFDeuel35 min
Jun 27, 8:24 PM MDTTornado WarningLBFKeith, Perkins61 min
Jun 27, 9:01 PM MDTTornado WarningLBFLincoln64 min
Jun 27, 10:24 PM MDTSevere Thunderstorm WarningLBFDeuel66 min
Jun 27, 10:44 PM MDTTornado WarningLBFDeuel66 min

The nearest sounding before it

N. Platte/Lee Bi, NE (KLBF), launched 00:00Z, 1.3 hours before the alert went out and 8 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 00:00Z on 1999-06-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 750 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 00:00Z on 1999-06-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 274 square meters per square second.1939587897Sfc1 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
750 J/kg
Mixed-layer CIN
-238 J/kg
Mixed-layer LCL
1318 m above ground
0-6 km bulk shear
54 kt
0-1 km storm-relative helicity
274 m²/s²
0-3 km storm-relative helicity
406 m²/s²
Significant tornado parameter
0.0
Supercell composite
10.2

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
Jun 27, 10:45 PM MDTSevere Thunderstorm WatchSPCKit Carson, Logan, Phillips, Sedgwick, Yuma6 hr

Nearby

Tornado Watches in Nebraska, 1999Tornado Watches in Colorado, 1999Every tornado watch in 1999

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.