Alert archive / Nebraska / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 196, NWS North Platte, NE

August 21, 1997Perkins County, Nebraska

NWS North Platte, NE issued this severe thunderstorm warning at Aug 21, 1997, 5:56 PM MDT for Perkins County, Nebraska. It was in force for 49 min. 5 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 21, 1997, 5:56 PM MDT (23:56 UTC)
Expired: Aug 21, 1997, 6:45 PM MDT
In force: 49 min
Issued by: NWS North Platte, NE
Area: Whole counties

County Perkins County, NE

What was reported inside it

Time	Report	Where	Remark
Aug 21, 6:08 PM MDT	Tornado F0	Venango, NE	The tornado touched down and remained in open fields north of Venango.
Aug 21, 6:12 PM MDT	Hail 1	Venango, NE
Aug 21, 6:21 PM MDT	Tornado F0	Venango, NE	The tornado traveled over open country south of Venango into northern Chase county or 7 miles north of Lamar. The weak tornado did little if any damage.
Aug 21, 6:30 PM MDT	Hail 1.75	Grant, NE
Aug 21, 6:45 PM MDT	Hail 2.75	Grant, NE

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

N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 11.9 hours before the alert went out and 93 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: 969 J/kg
Mixed-layer CIN: -157 J/kg
Mixed-layer LCL: 1037 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: 251 m²/s²
0-3 km storm-relative helicity: 348 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 2.8

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KLBF 212355 RRA
SVRLBF
NEC135-220045-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE NORTH PLATTE NE
656 PM CDT (556 PM MDT) THU AUG 21 1997

THE NATIONAL WEATHER SERVICE IN NORTH PLATTE NE HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 645 PM MDT (745 PM CDT)
FOR PEOPLE IN THE FOLLOWING LOCATION...

IN SOUTHWESTERN NEBRASKA

   ...PERKINS COUNTY
 
AT 555 PM MDT...A SEVERE THUNDERSTORM WAS INDICATED BY NORTH PLATTE
DOPPLER RADAR 23 MILES SOUTH SOUTHWEST OF OGALLALA OR 3 MILES NORTH
NORTHWEST OF BRANDON MOVING SOUTH SOUTHEAST AT 25 MPH.

DAMAGING HAIL AND/OR DESTRUCTIVE WINDS CAN BE EXPECTED NEAR...
  VENANGO                      BY 602 PM MDT
  BRANDON                      BY 602 PM MDT


 A TORNADO WATCH IS ALSO IN EFFECT.  SEVERE THUNDERSTORMS CAN
PRODUCE TORNADOES.
 
IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER FROM THE STORM IN A
STRONG BUILDING.  DAMAGING WIND...LARGE HAIL...VERY HEAVY RAIN AND
DEADLY LIGHTNING ARE ALL POSSIBLE IN SEVERE THUNDERSTORMS.  STAY
INSIDE AWAY FROM WINDOWS UNTIL THE STORM HAS PASSED.

SLM

What forecasters said that day

The local office's own words before this severe thunderstorm 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 severe thunderstorm warning went out at Aug 21, 2:06 PM MDT, 3 hours 50 minutes earlier.

Area forecast discussion, Aug 21, 2:06 PM MDT, 3 hours 50 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
305 PM CDT THU AUG 21 1997

FORECAST PROBLEM...CHANCES FOR THUNDERSTORMS TONIGHT AND FRIDAY...

CURRENT KLNX 88D RADAR INDICATING THUNDERSTORMS OVER THE ONL ZONE GROUP.
ONE OF THE STORMS HAS BEEN WARNED ON IN GARFIELD COUNTY. 18Z SURFACE
ANALYSIS SHOWING LOW PRESSURE OVER SOUTHWEST NEBRASKA WITH DEWPOINTS IN
THE MID 60S OVER SOUTHERN NEBRASKA AND 60S ELSEWHERE. WATER VAPOR
IMAGERY SHOWING SHORTWAVE MOVING INTO FA. VISIBLE SATELLITE INDICATING
SOME THUNDERSTORMS BEGINNING TO FIRE IN GARDEN COUNTY.

UPPER RIDGE SHOWN BY MODELS TO CONTINUE OVER THE ROCKIES WITH NEBRASKA
IN NORTHWEST FLOW THROUGH THE PERIOD. AT THE SURFACE...A TROUGH WILL IN
WESTERN NEBRASKA WILL PASS THROUGH LATE FRIDAY AFTERNOON AND NIGHT WITH
THUNDERSTORMS ALONG AND AHEAD OF THE TROUGH. THE TROUGH SHOULD BE
THROUGH MOST OF FA BY 12Z SATURDAY. THERE IS A CHANCE FOR SOME MORNING
STORMS NEAR ONL. SHORTWAVES WILL BE HARD TO TIME IN NORTHWEST FLOW.

TONIGHT...LBF SOUNDING AT 17Z SHOWING STRONG CAP OVER THE WEST...AND
EXPLAINS LACK OF DEVELOPMENT OVER THE AREA AT THIS TIME. A TEMPERATURE
OF 93 DEGREES IS NEEDED TO BREAK THE CAP. HOWEVER...WITH ABUNDANT
MOISTURE AND INSTABILITY THUNDERSTORMS WILL BE POSSIBLE. OTHERWISE...
AVERAGE RH OF 50 PERCENT INDICATES A PARTLY CLOUDY SKY. BOUNDARY LAYER
WINDS INDICATE SOUTHEAST 5-10.

FRIDAY...AVERAGE RH OF 40 PERCENT SHOULD ALLOW MOSTLY SUNNY SKIES
EXCEPT  PARTLY CLOUDY IN ANW-ONL GROUP WITH 50 PERCENT RH.
THUNDERSTORMS SHOULD DEVELOP BY LATE AFTERNOON NEAR TROUGH. BOUNDARY
LAYER WINDS INDICATE SOUTH 10-15.

FRIDAY NIGHT...PARTLY CLOUDY WITH SCATTERED THUNDERSTORMS ALONG AND
AHEAD OF TROUGH. BOUNDARY LAYER WINDS INDICATED SOUTH 5-10 SHIFTING TO
THE WEST BEHIND THE TROUGH.

SATURDAY...TROUGH SHOULD BE PAST MOST OF FA...EXCEPT FOR ONL GROUP.
WILL KEEP SOME MORNING POPS IN ONL GROUP. OTHERWISE...MOSTLY SUNNY
ACROSS FA WITH AVERAGE RH FROM 40-50 PERCENT. BOUNDARY LAYER WINDS WEST
5-10.

WILL FOLLOW NGM TEMPERATURE GUIDANCE.

LBF BE 058/087 059/090 060 313
OGA BE 057/087 060/091 059 323
IML BE 057/087 060/091 060 313
VTN BE 057/086 061/091 060 313
ONL BB 057/085 060/089 059 3-3

FS

In the hours before

Local storm report, Aug 21, 1:35 PM MDT, 4 hours 21 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE  NORTH PLATTE NE
235 PM CDT THU AUG 21 1997

TIME(CDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0228 PM    6 ENE BURWELL             NE   1.50 INCH HAIL
08/21/97   GARFIELD

0230 PM    4 E BURWELL               NE   1.75 INCH HAIL
08/21/97   GARFIELD

SLM

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 20, 6:37 PM MDT	Severe Thunderstorm Warning	LBF	Chase	63 min
Aug 21, 4:24 AM MDT	Severe Thunderstorm Warning	LBF	Brown	46 min
Aug 21, 5:24 AM MDT	Severe Thunderstorm Warning	LBF	Blaine	46 min
Aug 21, 6:00 AM MDT	Severe Thunderstorm Warning	LBF	Custer	65 min
Aug 21, 6:17 AM MDT	Severe Thunderstorm Warning	LBF	Cherry	48 min
Aug 21, 1:19 PM MDT	Severe Thunderstorm Warning	LBF	Garfield	31 min
Aug 21, 5:16 PM MDT	Severe Thunderstorm Warning	LBF	Deuel, Keith	49 min
Aug 21, 5:30 PM MDT	Severe Thunderstorm Warning	LBF	Keith	50 min

Nearby

Severe Thunderstorm Warnings in Nebraska, 1997 Every severe thunderstorm warning in 1997

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.