Alert archive / Nebraska / Tornado Warnings in 1999

Tornado Warning 59, NWS North Platte, NE

September 1, 1999Sheridan County, Nebraska

NWS North Platte, NE issued this tornado warning at Sep 1, 1999, 6:46 PM MDT for Sheridan County, Nebraska. It was in force for 59 min. 2 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: Sep 1, 1999, 6:46 PM MDT (00:46 UTC)
Expired: Sep 1, 1999, 7:45 PM MDT
In force: 59 min
Issued by: NWS North Platte, NE
Area: Whole counties

County Sheridan County, NE

The radar

The North Platte radar (KLNX), 163 km from the middle of the area, began a volume at 00:48 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.

What was reported inside it

Time	Report	Where	Remark
Sep 1, 7:00 PM MDT	Thunderstorm Wind 75	Ellsworth, NE	Several power poles were blown down.
Sep 1, 7:05 PM MDT	Hail 0.88	Ellsworth, 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

Rapid City, SD (KUNR), launched 00:00Z, 0.8 hours before the alert went out and 178 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1530 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 15 m²/s²
0-3 km storm-relative helicity: 4 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KLBF 020045 RRA
TORLBF
NEC161-020145-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE NORTH PLATTE NE
746 PM CDT (646 PM MDT) WED SEP 1 1999

THE NATIONAL WEATHER SERVICE IN NORTH PLATTE HAS ISSUED A

* TORNADO WARNING FOR...
  CENTRAL AND SOUTHERN SHERIDAN COUNTY IN THE NEBRASKA PANHANDLE

* UNTIL 745 PM MDT (845 PM CDT)

* AT 643 PM MDT... NORTH PLATTE DOPPLER RADAR INDICATED A POSSIBLE
TORNADO 10 MILES NORTH OF ELLSWORTH NEAR WALTERS LAKE.  THIS
TORNADO WAS PART OF A LINE OF SEVERE THUNDERSTORMS FROM SPRING
LAKE TO ELLSWORTH.  RADAR INDICATED BASEBALL SIZE HAIL ALONG
HIGHWAY 250 SIX MILES NORTH OF LAKESIDE. THE LINE WAS MOVING EAST AT
20 MPH.

THE TORNADO IS EXPECTED TO REMAIN IN RURAL AREAS.

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

BUTTLER

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 Sep 1, 11:43 AM MDT, 7 hours 3 minutes earlier.

Area forecast discussion, Sep 1, 11:43 AM MDT, 7 hours 3 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1240 PM CDT WED 1999

...FORECAST CHALLENGE CONTINUES TO BE POPS AND TEMPS...

SCT MID-LVL INSTABILITY AND -SHRA OVER MUCH OF CWA FROM IML TO VTN AT
15Z. LOW CIRC CENTERED OVER LBF AT 15Z IN ASSOC WITH SFC TROF. SFC FRONT
FM NR IML TO ANW. ETA SEEMS TO BE FAIRLY ON TRACK WITH PREVIOUS RUNS.

NGM PRECIPITATION FIELDS LOOK OVERDONE (AS THEY DID YESTERDAY AS
WELL...AND PROVED TO BE SO.) ALL MODELS (INCLUDING RUC AND MESOETA)
HOLD PRECIPITATION BACK TO THE NORTHWEST OF LBF UNTIL TONIGHT. ETA
VORTICITY REMAINS FAIRLY CHANNELIZED UNTIL THIS AFTERNOON...BUT SENDS
VORT MAX AFTER VORT MAX THROUGH THE FLOW THRU PD. DELINIATION BETWEEN
AREAS THAT GET WEATHER AND THOSE THAT DONT MAY BE SHARP DUE TO
AMPLIFICATION...AND TIGHT GRADIENT ALOFT. WE ARE NEAR THE INFLECTION
POINT...SO EASTERN ZONES WILL HAVE GREATEST AMOUNT OF UNCERTAINTY.
SWODY1 INDICATES AREA WILL BE IN THE RRQ OF JET. MORNING SOUNDING
PRECIPITABLE WATER LOOKS ABOUT AVERAGE FOR LBF AT .96 INCHES. CAP
STRENGTH STRONG OVER LBF...BUT IS TO ERODE WITH FROPA. CONVECTION TO
BEGIN ALONG FOOTHILLS AND SPREAD FROM WEST TO EAST SEEMS GENERAL
CONSENSUS. WILL GO WITH HIGHER POPS (IF PCPN ISNT ALREADY GOING BY ZONE
ISSUANCE TIME) FOR WESTERN ZONES. LOWEST POPS FOR ONL GROUPING THIS
EVE/TNT.

2ND/3RD PERIOD...ROUND TWO OF CONVECTIVE WEATHER THURSDAY AFTERNOON.
NEARLY STATIONARY FRONT SHIFTS SOMEWHAT NORTHEAST.  ALMOST ENTIRE CWA
IN DAY 2 SLIGHT RISK AS UPPER LEVEL TROF SHIFTS EAST. AM NOT GOING TO
STRAY FAR FROM FWC GUIDANCE WHERE ABLE TO USE. MRF GUIDANCE LOOKS TOO
COOL. WILL GO WITH 30 OR 40 POPS MOST AREAS AGAIN FOR THURSDAY. FRIDAY
IS SORT OF A BIG QUESTION MARK WITH THE MRF RUNNING COLD. THINK ILL
LEAVE POPS OUT FOR NOW EXCEPT FOR MAYBE MENTION IN NORTHWEST
COUNTIES...WORDED LATE AFTERNOON.

IN THE EXTENDED...MODELS CANT DECIDE IF THE TROF OVER THE WEST WILL
CUT OFF AFTER SATURDAY OR NOT.  MRF CUTS OFF THE LOW AND LIFTS IT
NORTHEAST.  ECMWF BRIEFLY CLOSES THE LOW FRIDAY BUT THEN OPENS IT UP
AGAIN BY SATURDAY MORNING...GIVING IT A NEGATIVE TILT WHILE LIFTING IT
NORTHEAST. PROBABLY THE SAFEST THING TO DO IS GO WITH CHANCES EACH DAY.
EVEN IF THE MRF WERE TO VERIFY...I HAVE A HARD TIME BELIEVING THE 64
DEGREES FOR A HIGH SATURDAY AT LBF SINCE THE MRF ALSO HAS SFC RIDGING
TAKING PLACE AT THAT TIME. FEEL HIGHS IN THE UPPER 70S TO MID 80S WILL
LIKELY COVER IT...WITH LOWS IN THE 50S AND 60S.

.LBF...NONE.

SLM

In the hours before

Local storm report, Sep 1, 6:05 PM MDT, 41 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE  NORTH PLATTE NE
705 PM CDT WED SEP 1 1999

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

0700 PM    5 W ANTIOCH               NE   0.75 INCH HAIL
09/01/99   SHERIDAN

DP

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 1, 6:35 PM MDT	Severe Thunderstorm Warning	LBF	Garden	60 min
Sep 1, 7:08 PM MDT	Tornado Warning	LBF	Cherry	62 min
Sep 1, 7:33 PM MDT	Severe Thunderstorm Warning	LBF	Grant	62 min
Sep 1, 7:44 PM MDT	Severe Thunderstorm Warning	LBF	Cherry	61 min
Sep 1, 8:09 PM MDT	Severe Thunderstorm Warning	LBF	Arthur	66 min
Sep 1, 8:55 PM MDT	Severe Thunderstorm Warning	LBF	McPherson	45 min
Sep 2, 5:06 PM MDT	Flash Flood Warning	LBF	Chase, Hayes, Lincoln, Perkins	114 min
Sep 2, 5:50 PM MDT	Severe Thunderstorm Warning	LBF	Hayes	50 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.