Alert archive / Nebraska / Tornado Warnings in 1999

Tornado Warning 26, NWS North Platte, NE

June 24, 1999Cherry County, Nebraska

NWS North Platte, NE issued this tornado warning at Jun 24, 1999, 7:44 AM MDT for Cherry County, Nebraska. It was in force for 46 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jun 24, 1999, 7:44 AM MDT (13:44 UTC)
Expired: Jun 24, 1999, 8:30 AM MDT
In force: 46 min
Issued by: NWS North Platte, NE
Area: Whole counties

County Cherry County, NE

The radar

The North Platte radar (KLNX), 79 km from the middle of the area, began a volume at 13:48 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, 1.7 hours before the alert went out and 163 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1670 J/kg
Mixed-layer CIN: -109 J/kg
Mixed-layer LCL: 1032 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 45 m²/s²
0-3 km storm-relative helicity: 90 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

959 
WFUS1 KLBF 241342 RRA
TORLBF
NEC031-241430-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE NORTH PLATTE NE
844 AM CDT (744 AM MDT) THU JUN 24 1999

THE NATIONAL WEATHER SERVICE IN NORTH PLATTE HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTHWESTERN CHERRY COUNTY IN NORTH CENTRAL NEBRASKA

* UNTIL 930 AM CDT

* AT 842 AM CDT... NORTH PLATTE DOPPLER RADAR INDICATED A
  POSSIBLE TORNADO 33 MILES NORTHWEST OF MULLEN... MOVING EAST AT 15
  MPH.

THE TORNADO IS EXPECTED TO REMAIN IN RURAL AREAS ALONG AND EAST OF
HIGHWAY 61...AND SOUTHWEST OF MERRITT RESERVOIR.

GO TO THE BASEMENT OR A SMALL INTERIOR ROOM ON THE LOWEST FLOOR

JWS

What forecasters said that day

The local office's own words before this tornado warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS North Platte, NE wrote its last area forecast discussion before this tornado warning went out at Jun 24, 1:55 AM MDT, 5 hours 49 minutes earlier.

Area forecast discussion, Jun 24, 1:55 AM MDT, 5 hours 49 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
255 AM CDT THU JUN 24 1999

...FORECAST CHALLENGE...TEMPERATURES AND THE POTENTIAL FOR LEESIDE
CONVECTION.

...SYNOPSIS...
   A WEAK SURFACE FRONT WAS LOCATED IN CENTRAL AND NORTHERN NEBRASKA.
IN THE UPPER LEVELS...SATELLITE IMAGERY AND WIND PROFILERS SHOWED
ZONAL FLOW THROUGH THE NORTHERN PLAINS WITH A SERIES OF SHORT WAVE
TROUGHS...THE NEAREST OF WHICH SEEMED TO BE ENHANCING THE CONVECTION IN
EASTERN COLORADO.
...MODEL PERFORMANCE...
    THE ETA SEEMS TO BE THE BEST MODEL FOR THIS FORECAST CYCLE FOR ITS
RESOLUTION. THE AVN AND ETA ARE BOTH SHOWING GOOD RUN-TO-RUN CONSISTENCY
AMONG THE LATEST THREE MODEL RUNS WITH THE UPPER LEVEL HEIGHTS AND
VORTICITY AND WITH THE HEIGHTS AND TEMPERATURES IN THE LOWER LEVELS.
ALSO...THE PREVIOUS RUN OF THE AVN AND ETA DID WELL WITH THE UPPER
LEVEL FEATURES AT 06Z.

...TODAY AND TONIGHT...
    THE COMBINATION OF LOW-LEVEL CONVERGENCE IN THE LEE TROUGH AND
INCREASING INSTABILITY SHOULD PRODUCE A FEW THUNDERSTORMS IN WESTERN
NEBRASKA IN THE 700MB THETA-E RIDGE IN EASTERN COLORADO AND SOUTHWEST
NEBRASKA. AFTER 00Z THIS EVENING...THE AXIS OF THE THETA-E RIDGE AT
850MB ON A PHP-OGA-LIC LINE PHASES WITH THE ONE AT 700MB. HOWEVER...
THE LOWER AND MIDDLE LEVELS ARE VERY DRY WITH 850MB CONDENSATION
DEFICITS OF 150MB OR HIGHER IN THE CONVERGENCE ZONE AND THE THETA-E
RIDGE. SO...SEE NO REASON TO GO HIGHER THAN THE CURRENT FORECAST OF 20
PERCENT TODAY AND TONIGHT. REGARDING TEMPERATURES...850MB TEMPERATURE
INCREASES OF 2-3C SUPPORT HIGHS TODAY OF 85-90F.
...THIRD PERIOD...
    BY FRIDAY EVENING...Q-VECTOR CONVERGENCE IS STRONGER IN THE
850-700MB AND 700-500MB LAYER IN MUCH OF THE FORECAST AREA. HOWEVER...
VERY DRY LOW AND MID LEVELS CONTINUE. WARM ADVECTION INCREASES THE
850-500MB LAPSE RATES TO 8-9C/KM IN THE WEST WITH THE PERSISTENT
INSTABILITY IN THE THETA-E RIDGE. SO...THUNDERSTORMS ARE AGAIN POSSIBLE
FRIDAY EVENING. THAT IS IN THE EXTENDED PERIOD THOUGH. WITH LOW LEVEL
TEMPERATURE CHANGES OF 5-10C FROM TODAY...TEMPERATURES EXCEEDING 100F
ARE POSSIBLE IN THE PANHANDLE WITH FULL SUN. HOWEVER...CONSIDERING THE
LIKELIHOOD OF MID CLOUDS WITH ELEVATED CONVECTION...WILL DEFER TO THE
CURRENT FORECAST.
...EXTENDED PERIOD...
    WILL ADD FRIDAY NIGHT IN THE FOURTH PERIOD FOR CONTINUITY.
OTHERWISE...NO CHANGE.

.LBF...NONE

SPRINGER

In the hours before

Special weather statement, Jun 24, 4:20 AM MDT, 3 hours 24 minutes before

NEZ004>010-022>029-035>038-056>059-069>071-241630-

SEVERE WEATHER OUTLOOK FOR WESTERN AND NORTH CENTRAL NEBRASKA
NATIONAL WEATHER SERVICE NORTH PLATTE NE
520 AM CDT THU JUN 24 1999

...STORM SPOTTER ACTIVATION MAY BE REQUIRED IN WESTERN AND NORTH
CENTRAL NEBRASKA THIS EVENING AND TONIGHT...

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS NORTH AND WEST OF A
LINE FROM VALENTINE TO IMPERIAL. WITH VERY WARM HUMID
CONDITIONS THIS AFTERNOON AND EVENING STORMS DEVELOPING ALONG A
STATIONARY FRONT COULD BECOME SEVERE. THE GREATEST SEVERE WEATHER
THREAT IS DAMAGING WIND AND LARGE HAIL.

ON FRIDAY...DRYER CONDITIONS WILL KEEP STRONG THUNDERSTORMS FROM
DEVELOPING.

SPRINGER

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 23, 8:29 PM MDT	Severe Thunderstorm Warning	LBF	Thomas	66 min
Jun 24, 3:05 AM MDT	Severe Thunderstorm Warning	LBF	Arthur, Garden	65 min
Jun 24, 5:06 AM MDT	Severe Thunderstorm Warning	LBF	Arthur, McPherson	64 min
Jun 24, 6:28 AM MDT	Severe Thunderstorm Warning	LBF	Brown, Rock	32 min
Jun 24, 7:30 AM MDT	Severe Thunderstorm Warning	LBF	Cherry	65 min
Jun 24, 8:10 AM MDT	Severe Thunderstorm Warning	LBF	Grant, Hooker	65 min
Jun 24, 8:32 AM MDT	Severe Thunderstorm Warning	LBF	Cherry	33 min
Jun 24, 9:15 AM MDT	Severe Thunderstorm Warning	LBF	Hooker	65 min

Nearby

Tornado Warnings in Nebraska, 1999 Every tornado warning in 1999 Tornadoes 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.