Alert archive / Nebraska / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 66, NWS North Platte, NE

May 21, 1998McPherson County, Nebraska

NWS North Platte, NE issued this severe thunderstorm warning at May 21, 1998, 3:09 PM CDT for McPherson County, Nebraska. It was in force for 66 min. 1 report 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, 3:09 PM CDT (20:09 UTC)
Expired: May 21, 1998, 4:15 PM CDT
In force: 66 min
Issued by: NWS North Platte, NE
Area: Whole counties

County McPherson County, NE

The radar

The North Platte radar (KLNX), 59 km from the middle of the area, began a volume at 20:12 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, 3:20 PM CDT	Hail 0.75	Tryon, NE	Thunderstorm winds caused damage to trees.

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, 8.2 hours before the alert went out and 62 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: 379 J/kg
Mixed-layer CIN: -274 J/kg
Mixed-layer LCL: 943 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: -32 m²/s²
0-3 km storm-relative helicity: 128 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.

292 
WUUS1 KLBF 212005 RRA
SVRLBF
NEC117-212115-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE NORTH PLATTE NE
309 PM CDT THU MAY 21 1998

THE NATIONAL WEATHER SERVICE IN NORTH PLATTE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL AND WESTERN MCPHERSON COUNTY IN WEST CENTRAL NEBRASKA

* UNTIL 415 PM CDT

* AT 308 PM CDT... NORTH PLATTE DOPPLER RADAR INDICATED A SEVERE
  THUNDERSTORM 27 MILES SOUTH SOUTHWEST OF MULLEN OR 15 MILES WEST
  NORTHWEST OF TRYON MOVING SOUTH SOUTHEAST AT 20 MPH.

* DAMAGING HAIL AND/OR DESTRUCTIVE WINDS CAN BE EXPECTED NEAR...
  TRYON                        BY 345 PM CDT

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.

WERT

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, 2:46 PM CDT, 23 minutes earlier.

Area forecast discussion, May 21, 2:46 PM CDT, 23 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, 10:57 AM CDT, 4 hours 12 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE  NORTH PLATTE NE
1057 AM CDT THU MAY 21 1998

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

0730 AM    16 NW HAYES CENTER        NE   1.00 INCH HAIL
05/21/98   HAYES

M. MUTCHLER

Local storm report, May 21, 10:57 AM CDT, 4 hours 12 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE  NORTH PLATTE NE
1057 AM CDT THU MAY 21 1998

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

0730 AM    16 NW HAYES CENTER        NE   1.00 INCH HAIL
05/21/98   HAYES

M. MUTCHLER

Local storm report, May 21, 11:10 AM CDT, 3 hours 59 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE  NORTH PLATTE NE
1110 AM CDT THU MAY 21 1998

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

1000 PM    10 NE CHAPPELL            NE   0.75 INCH HAIL
05/20/99   DEUEL

0540 AM    2 E VENANGO               NE   WIND DAMAGE
05/21/98   PERKINS                        LARGE TREE LIMBS DOWN

BOWMAN

Local storm report, May 21, 11:10 AM CDT, 3 hours 59 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE  NORTH PLATTE NE
1110 AM CDT THU MAY 21 1998

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

1000 PM    10 NE CHAPPELL            NE   0.75 INCH HAIL
05/20/99   DEUEL

0540 AM    2 E VENANGO               NE   WIND DAMAGE
05/21/98   PERKINS                        LARGE TREE LIMBS DOWN

BOWMAN

Special weather statement, May 21, 11:11 AM CDT, 3 hours 58 minutes before

NEZ004>010-022>029-035>038-056>059-069>071-221200-

SEVERE WEATHER OUTLOOK FOR WESTERN AND NORTH CENTRAL NEBRASKA
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1110 AM CDT (1010 AM MDT) THU MAY 21 1998

THIS OUTLOOK PERTAINS TO THE FOLLOWING NEBRASKA COUNTIES...

ARTHUR     BLAINE     BOYD       BROWN      CHASE      CHERRY
CUSTER     DEUEL      FRONTIER   GARDEN     GARFIELD   GRANT
HAYES      HOLT       HOOKER     KEITH      KEYA PAHA  LINCOLN
LOGAN      LOUP       MCPHERSON  PERKINS    ROCK       SHERIDAN
THOMAS     WHEELER

...STORM SPOTTER ACTIVATION WILL LIKELY BE NEEDED THIS AFTERNOON AND
TONIGHT ACROSS MOST OF WESTERN AND NORTH CENTRAL NEBRASKA...

THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS LATE THIS AFTERNOON
AND TONIGHT SOUTH AND WEST OF A LINE FROM RUSHVILLE TO BROKEN BOW. A
SLIGHT RISK OF SEVERE THUNDERSTORMS EXISTS ACROSS THE REMAINDER OF THE
OUTLOOK AREA.

A STATIONARY FRONT WILL REMAIN ALONG THE KANSAS AND NEBRASKA BORDER
THROUGH TONIGHT. ALONG AND NORTH OF THIS FRONT...MOISTURE WILL BE
PLENTIFUL IN THE LOW LEVELS AND WITH ADEQUATE AFTERNOON HEATING
EXPECTED...CONDITIONS WILL BECOME FAVORABLE FOR THE DEVELOPMENT OF
THUNDERSTORMS BY LATE AFTERNOON WEST OF A LINE FROM RUSHVILLE TO HAYES
CENTER. AS AN UPPER LEVEL DISTURBANCE MOVES OVER THE AREA THIS
EVENING...ANY THUNDERSTORMS THAT DEVELOP WILL HAVE THE POTENTIAL TO
BECOME SEVERE RAPIDLY...ESPECIALLY IN THE MODERATE RISK AREA.

THE MAIN SEVERE WEATHER THREAT WILL BE LARGE HAIL AND DAMAGING
WINDS...HOWEVER WIND PROFILES THROUGH THE ATMOSPHERE WILL BECOME
CONDUCIVE FOR DEVELOPING THUNDERSTORMS CAPABLE OF PRODUCING TORNADOES BY
LATE AFTERNOON AND EVENING IN THE MODERATE RISK AREA. PERSONS PLANNING
ANY OUTDOOR ACTIVITIES THIS AFTERNOON ADN TONIGHT SHOULD MONITOR NOAA
WEATHER RADIO AND LOCAL MEDIA OUTLETS FOR FURTHER INFORMATION
THROUGHOUT THE DAY.

STOPPKOTTE

Local storm report, May 21, 11:16 AM CDT, 3 hours 53 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE  NORTH PLATTE NE
1116 AM CDT THU MAY 21 1998

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

1000 PM    12 S OSHKOSH              NE   0.75 INCH HAIL
05/20/99   GARDEN                         HAIL DRIFTED AGAINST
                                          BUILDINGS

SPRINGER

The office that day

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

Issued	Product	Office	Counties	Lasted
May 20, 9:11 PM CDT	Tornado Warning	LBF	Deuel, Garden	64 min
May 20, 10:14 PM CDT	Severe Thunderstorm Warning	LBF	Garden	61 min
May 20, 10:28 PM CDT	Severe Thunderstorm Warning	LBF	Cherry	62 min
May 20, 10:52 PM CDT	Severe Thunderstorm Warning	LBF	Deuel	63 min
May 21, 5:26 AM CDT	Severe Thunderstorm Warning	LBF	Chase	64 min
May 21, 5:33 AM CDT	Severe Thunderstorm Warning	LBF	Perkins	62 min
May 21, 6:36 AM CDT	Severe Thunderstorm Warning	LBF	Perkins	64 min
May 21, 7:15 AM CDT	Severe Thunderstorm Warning	LBF	Hayes	50 min
May 21, 7:29 AM CDT	Severe Thunderstorm Warning	LBF	Keith	46 min
May 21, 7:36 AM CDT	Severe Thunderstorm Warning	LBF	Lincoln	64 min
May 21, 7:40 AM CDT	Severe Thunderstorm Warning	LBF	Perkins	50 min
May 21, 7:44 AM CDT	Severe Thunderstorm Warning	LBF	Frontier	66 min
May 21, 8:27 AM CDT	Severe Thunderstorm Warning	LBF	Frontier	63 min
May 21, 8:38 AM CDT	Severe Thunderstorm Warning	LBF	Lincoln	62 min
May 21, 9:28 AM CDT	Severe Thunderstorm Warning	LBF	Frontier	32 min
May 21, 2:19 PM CDT	Severe Thunderstorm Warning	LBF	Arthur	66 min
May 21, 2:33 PM CDT	Severe Thunderstorm Warning	LBF	Grant, Hooker	62 min
May 21, 3:57 PM CDT	Severe Thunderstorm Warning	LBF	Hooker, McPherson, Thomas	63 min
May 21, 4:03 PM CDT	Severe Thunderstorm Warning	LBF	Keith, Lincoln	62 min
May 21, 6:38 PM CDT	Severe Thunderstorm Warning	LBF	Frontier	62 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.