Alert archive / Colorado / Tornado Warnings in 1998

Tornado Warning 4, NWS Denver/Boulder, CO

May 21, 1998Phillips County, Sedgwick County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at May 21, 1998, 6:13 PM MDT for Phillips County, Sedgwick County, Colorado. It was in force for 22 min. 1 report came from inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties, with what was reported inside it.

The facts

Issued
May 21, 1998, 6:13 PM MDT (00:13 UTC)
Expired
May 21, 1998, 6:35 PM MDT
In force
22 min
Issued by
NWS Denver/Boulder, CO
Area
Whole counties; the outline is the Mesonet’s reconstruction

Counties Phillips County, CO, Sedgwick County, CO

The radar

The Goodland radar (KGLD), 161 km from the middle of the area, began a volume at 00:16 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

TimeReportWhereRemark
May 21, 6:15 PM MDTHail 2.75Amherst, CO

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.

IssuedProductOfficeLasted
May 21, 2:15 PM MDTTornado WatchSPC6 hr

The nearest sounding before it

Denver, CO (KDNR), launched 00:00Z, 0.2 hours before the alert went out and 135 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-pSkew-T log-p diagram, Denver, CO at 00:00Z on 1998-05-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 600 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Denver, CO at 00:00Z on 1998-05-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -67 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
600 J/kg
Mixed-layer CIN
-98 J/kg
Mixed-layer LCL
2597 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
-67 m²/s²
0-3 km storm-relative helicity
92 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.

854 
WFUS1 KDEN 220017 RRA
TORDEN
COC095-115-220035-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DENVER CO
613 PM MDT THU MAY 21 1998

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

* TORNADO WARNING FOR...
     NORTHEASTERN PHILLIPS COUNTY IN NORTHEAST COLORADO
     SOUTHEASTERN SEDGWICK COUNTY IN NORTHEAST COLORADO

* UNTIL 635 PM MDT

* AT 608 PM MDT...THE WAS A SEVERE THUNDERSTORM WITH A POSSIBLE 
TORNADO OVER AMHERST...OR  ABOUT 11 MILES NORTHEAST OF 
HOLYOKE...MOVING EAST AT 25 MILES PER  HOUR.

* LOCATIONS IN THE WARNING INCLUDE...AMHERST AND SIXTEEN-MILE CORNER


TENNIS SIZE HAIL HAS BEEN REPORTED WITH THIS STORM. THIS WARNING 
REPLACES THE EARLIER TORNADO WARNING FOR THE ABOVE AREA.

THE SAFEST PLACE TO BE DURING A TORNADO IS IN A BASEMENT. GET UNDER A
WORKBENCH OR OTHER PIECE OF STURDY FURNITURE. IF NO BASEMENT IS
AVAILABLE...SEEK SHELTER ON THE LOWEST FLOOR OF THE BUILDING IN AN
INTERIOR HALLWAY OR ROOM SUCH AS A CLOSET. USE BLANKETS OR PILLOWS TO
COVER YOUR BODY AND ALWAYS STAY AWAY FROM WINDOWS.

ENTREKIN

LAT...LON 4079 10224 4064 10219 4069 10205 4094 10205

The office that day

Everything else NWS Denver/Boulder, CO issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 21, 6:15 PM MDTSevere Thunderstorm WarningBOULogan45 min
May 21, 7:27 PM MDTSevere Thunderstorm WarningBOUMorgan, Weld33 min
May 21, 8:01 PM MDTSevere Thunderstorm WarningBOUMorgan, Weld39 min
May 21, 8:55 PM MDTSevere Thunderstorm WarningBOULogan, Phillips35 min
May 21, 10:36 PM MDTSevere Thunderstorm WarningBOUAdams, Weld34 min
May 22, 11:56 AM MDTSevere Thunderstorm WarningBOUBoulder, Jefferson34 min
May 22, 12:29 PM MDTSevere Thunderstorm WarningBOUBoulder, Jefferson, Weld46 min
May 22, 12:29 PM MDTSevere Thunderstorm WarningBOUAdams46 min
May 22, 1:00 PM MDTSevere Thunderstorm WarningBOUAdams, Weld30 min
May 22, 1:10 PM MDTSevere Thunderstorm WarningBOUBoulder, Larimer, Weld25 min
May 22, 1:30 PM MDTSevere Thunderstorm WarningBOUAdams, Weld45 min
May 22, 1:35 PM MDTSevere Thunderstorm WarningBOULarimer, Weld40 min
May 22, 1:41 PM MDTSevere Thunderstorm WarningBOUWeld34 min
May 22, 2:06 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe, Denver39 min
May 22, 2:15 PM MDTSevere Thunderstorm WarningBOUMorgan, Weld45 min
May 22, 2:21 PM MDTSevere Thunderstorm WarningBOUWeld24 min
May 22, 2:45 PM MDTSevere Thunderstorm WarningBOUMorgan, Weld45 min
May 22, 2:58 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe32 min
May 22, 3:15 PM MDTSevere Thunderstorm WarningBOUMorgan, Weld40 min
May 22, 3:21 PM MDTTornado WarningBOUAdams, Arapahoe24 min
May 22, 3:55 PM MDTSevere Thunderstorm WarningBOUMorgan, Washington35 min
May 22, 4:11 PM MDTSevere Thunderstorm WarningBOUAdams34 min
May 22, 4:30 PM MDTSevere Thunderstorm WarningBOULogan, Morgan, Washington30 min
May 22, 4:40 PM MDTSevere Thunderstorm WarningBOUWashington50 min
May 22, 4:46 PM MDTSevere Thunderstorm WarningBOUAdams, Washington44 min

Nearby

Tornado Warnings in Colorado, 1998Every tornado warning in 1998Tornadoes 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.