Alert archive / Nebraska / Severe Thunderstorm Watches in 2001

Severe Thunderstorm Watch 598

July 20, 200130 counties in Nebraska

The Storm Prediction Center issued this severe thunderstorm watch at Jul 20, 2001, 4:15 PM MDT for 30 counties in Nebraska. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Jul 20, 2001, 4:15 PM MDT (22:15 UTC)
Expired
Jul 20, 2001, 9:00 PM MDT
In force
5 hr
Issued by
the Storm Prediction Center
All 30 counties

Arthur County, NE, Blaine County, NE, Box Butte County, NE, Buffalo County, NE, Chase County, NE, Cherry County, NE, Custer County, NE, Dawes County, NE, Dawson County, NE, Deuel 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, Lincoln County, NE, Logan County, NE, McPherson County, NE, Perkins County, NE, Phelps County, NE, Red Willow County, NE, Sheridan County, NE, Thomas County, NE

The radar

The North Platte radar (KLNX), 44 km from the middle of the area, began a volume at 22:16 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 nearest sounding before it

N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 10.3 hours before the alert went out and 78 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 2001-07-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 449 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 2001-07-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -29 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
449 J/kg
Mixed-layer CIN
-280 J/kg
Mixed-layer LCL
1318 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
-29 m²/s²
0-3 km storm-relative helicity
75 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

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
Jul 19, 6:30 PM MDTSevere Thunderstorm WatchSPCAdams, Buffalo, Custer, Dawson, Franklin, Frontier and 15 more6 hr

Nearby

Severe Thunderstorm Watches in Nebraska, 2001Every severe thunderstorm watch in 2001

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.