Alert archive / Nebraska / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 73, NWS North Platte, NE

May 21, 1998Chase County, Nebraska

NWS North Platte, NE issued this severe thunderstorm warning at May 21, 1998, 10:13 PM MDT for Chase County, Nebraska. It was in force for 62 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: May 21, 1998, 10:13 PM MDT (04:13 UTC)
Expired: May 21, 1998, 11:15 PM MDT
In force: 62 min
Issued by: NWS North Platte, NE
Area: Whole counties

County Chase County, NE

The radar

The Goodland radar (KGLD), 129 km from the middle of the area, began a volume at 04:13 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
May 21, 10:30 PM MDT	Hail 1.75	Champion, NE	Large hail destroyed up to 2000 acres of wheat.
May 21, 10:55 PM MDT	Hail 0.75	Enders, 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
May 21, 7:30 PM MDT	Tornado Watch	SPC	6 hr

The nearest sounding before it

N. Platte/Lee Bi, NE (KLBF), launched 00:00Z, 4.2 hours before the alert went out and 114 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: 685 J/kg
Mixed-layer CIN: -16 J/kg
Mixed-layer LCL: 548 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: 34 m²/s²
0-3 km storm-relative helicity: 73 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KLBF 220410 RRA
SVRLBF
NEC029-220515-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1113 PM CDT (1013 PM MDT) THU MAY 21 1998

THE NATIONAL WEATHER SERVICE IN NORTH PLATTE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WESTERN CHASE COUNTY IN SOUTHWESTERN NEBRASKA

* UNTIL 1115 PM MDT (1215 AM CDT)

* AT 1011 PM MDT... NORTH PLATTE DOPPLER RADAR INDICATED A SEVERE
  THUNDERSTORM 22 MILES WEST OF IMPERIAL OR 15 MILES WEST OF
  CHAMPION MOVING EAST AT 25 MPH.

* DAMAGING HAIL AND/OR DESTRUCTIVE WINDS CAN BE EXPECTED NEAR...
  CHAMPION                     BY 1040 PM MDT

A TORNADO WATCH IS IN EFFFECT! GO INSIDE A STURDY BUILDING AND
STAY AWAY FROM WINDOWS! SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES WITH LITTLE OR NO ADVANCE WARNING.

SPARKER

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 May 21, 1:46 PM MDT, 8 hours 27 minutes earlier.

Area forecast discussion, May 21, 1:46 PM MDT, 8 hours 27 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
246 PM CDT THU MAY 21 1998

TEMPS ARE THE MAIN CONCERN...WITH TSRA/HVY RAIN ALWAYS A PROBLEM...

SFC MAP AT 18Z STILL SHOWS THE FRONT WELL DOWN INTO CENTRAL KS THEN A
TROF LOCATED ALONG THE WY/NEBR BORDER. LOW CLOUDS HANGING TOUGH IN THE
NC AND PARTS OF THE SW WHERE TEMPS ARE STRUGGLING TO REACH 65. WINDS
ALSO MORE NRLY THAN ERLY ATTM.

MODELS CONTINUE IN FAIR AGREEMENT WITH MAIN UPPER FLOW WITH DIFFERNCES
CONTINUING IN POSITIONING OF VARIOUS SHORT WAVES MOVING ALONG THE MEAN
FLOW. ETA STILL LOOKS BEST BASED ON POSITION OF MID LEVEL SHORT WAVE AT
18Z. AS SHORT WAVE APPROACHES...MID LEVEL WINDS WILL BECOME MORE SRLY
AND INCREASE WHICH WILL SERVE TO ENHANCE ISENTROPIC LIFT IN THE
306-309K LAYER WHICH AT 18Z WAS PROGGING BEST LIFT IN THE TRI-STATE
AREA OF CO/WY/NEB. THIS AREA OF LIFT MOVES EWD IN TIME TWD THE SRN
PANHANDLE. AT THE SAME TIME...UPPER LEVEL DIFFLUENT FLOW ALSO BECOMES
DIVERGENT IN THE PANHANDLE AREA AS SPEED MAX MOVES NWD AND LEFT EXIT
REGION IS ENHANCED BY CYCLONIC FLOW. ALL THIS POINTS TO GOOD TSRA
DEVELOPMENT IN THE SRN NEBR PANHANDLE ESPECIALLY SINCE SOME SUNSHINE
HAS LED TO BETTER DESTABILIZATION THERE...WITH GOES-8/9 DATA SHOWING
LIS OF -6 TO -7 AND CAPES OF 1500-2000 J/KG THERE AT 100 PM CDT.
ANOTHER AREA WHICH WILL NEED ATTENTION EVENTUALLY IS IN SC/SERN NEBR
WHERE GOOD POTENTIAL FOR MCS EXISTS FOR LATER THIS EVENING. WILL ALSO
NEED TO MONITOR FOR HEAVY RAIN WITH TSRA IN THE SWRN PART OF CWA.

FOR SAT...LOW LEVEL TROF AXIS BECOMES NEG TILTED AND SHIFTS INTO THE
MIDDLE OF THE STATE FROM NW TO SE. WITH STRONG SHORT WAVE PROGGED TO
MOVE THRU THE STATE...TSRA POSSIBLE ONCE AGAIN. SUNSHINE WILL AGAIN BE
LIMITED...BUT QUITE COLD 500 MB TEMPS WILL MOVE OVER THE AREA AS WELL
WHICH SHOULD LEAD TO SOME ELEVATED CONVECTION AT LEAST. TEMPS WILL BE
HELD DOWN UNDER COLD CORE LOW...AND WILL LEAN TWD A SMALLER DIURNAL
RANGE.

FEWER CLOUDS EXPECTED INITIALLY SUNDAY...ALTHO ANY SUNSHINE SHOULD LEAD
TO THE DEVELOPMENT OF CU PRETTY READILY WITH COLDEST 500 TEMPS STILL
OVER THE AREA. WILL GO WITH A BLEND OF GUIDANCE...PROBABLY MORE TWD
COOLER GUIDANCE IN THE NC.

PRELIMINARY GUIDANCE FOR COORDINATION ONLY. OFFICIAL FORECASTS ARE
CONTAINED WITHIN PRODUCT OMAZFPNE...

CCF
LBF EB 051/067 049/072 049 543
OGA EB 052/068 050/071 050 543
ONL EE 052/065 050/067 050 365
VTN EE 050/064 046/067 046 465

STOPPKOTTE

In the hours before

Local storm report, May 21, 8:39 PM MDT, 1 hour 34 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE  NORTH PLATTE NE
939 PM CDT THU MAY 21 1998

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

0937 PM    WELLFLEET                 NE   0.75 INCH HAIL
05/21/98   LINCOLN

SPARKER

Local storm report, May 21, 8:39 PM MDT, 1 hour 34 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE  NORTH PLATTE NE
939 PM CDT THU MAY 21 1998

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

0937 PM    WELLFLEET                 NE   0.75 INCH HAIL
05/21/98   LINCOLN

SPARKER

Local storm report, May 21, 8:45 PM MDT, 1 hour 28 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE  NORTH PLATTE NE
945 PM CDT THU MAY 21 1998

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

0905 PM    7 SSW GRANT               NE   1.75 INCH HAIL
05/21/98   PERKINS

ROBERG

Local storm report, May 21, 8:45 PM MDT, 1 hour 28 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE  NORTH PLATTE NE
945 PM CDT THU MAY 21 1998

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

0905 PM    7 SSW GRANT               NE   1.75 INCH HAIL
05/21/98   PERKINS

ROBERG

Local storm report, May 21, 9:41 PM MDT, 32 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE  NORTH PLATTE NE
1041 PM CDT THU MAY 21 1998

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

0945 PM    17 WSW STOCKVILLE         NE   1.75 INCH HAIL
05/21/98   FRONTIER

ROBERG

Local storm report, May 21, 9:41 PM MDT, 32 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE  NORTH PLATTE NE
1041 PM CDT THU MAY 21 1998

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

0945 PM    17 WSW STOCKVILLE         NE   1.75 INCH HAIL
05/21/98   FRONTIER

ROBERG

The office that day

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

Issued	Product	Office	Counties	Lasted
May 21, 6:01 PM MDT	Tornado Warning	LBF	Frontier	34 min
May 21, 6:13 PM MDT	Tornado Warning	LBF	Perkins	32 min
May 21, 6:19 PM MDT	Severe Thunderstorm Warning	LBF	Lincoln	66 min
May 21, 6:38 PM MDT	Tornado Warning	LBF	Frontier	32 min
May 21, 6:44 PM MDT	Severe Thunderstorm Warning	LBF	Chase, Perkins	66 min
May 21, 6:48 PM MDT	Tornado Warning	LBF	Chase, Perkins	62 min
May 21, 7:29 PM MDT	Tornado Warning	LBF	Hayes	66 min
May 21, 7:59 PM MDT	Tornado Warning	LBF	Hayes	66 min
May 21, 8:08 PM MDT	Severe Thunderstorm Warning	LBF	Perkins	47 min
May 21, 8:26 PM MDT	Tornado Warning	LBF	Frontier	64 min
May 21, 8:59 PM MDT	Tornado Warning	LBF	Frontier	66 min
May 21, 10:46 PM MDT	Severe Thunderstorm Warning	LBF	Chase	44 min

Nearby

Severe Thunderstorm Warnings in Nebraska, 1998 Every severe thunderstorm warning in 1998

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.