Alert archive / Colorado / Tornado Warnings in 1998

Tornado Warning 2, NWS Denver/Boulder, CO

May 21, 1998Phillips County, Sedgwick County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at May 21, 1998, 5:41 PM MDT for Phillips County, Sedgwick County, Colorado. It was in force for 39 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
May 21, 1998, 5:41 PM MDT (23:41 UTC)
Expired
May 21, 1998, 6:20 PM MDT
In force
39 min
Issued by
NWS Denver/Boulder, CO
Area
Whole counties

Counties Phillips County, CO, Sedgwick County, CO

The radar

The Goodland radar (KGLD), 162 km from the middle of the area, began a volume at 23:40 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, 5:45 PM MDTHail 1.75Holyoke, CO
May 21, 5:57 PM MDTHail 1Holyoke, CO
May 21, 6:02 PM MDTHail 1.75Julesburg, CO
May 21, 6:07 PM MDTHail 2.5Julesburg, CO
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 12:00Z, 11.7 hours before the alert went out and 121 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 12:00Z on 1998-05-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Denver, CO at 12:00Z on 1998-05-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 56 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2454 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
56 m²/s²
0-3 km storm-relative helicity
158 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

The office that day

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

IssuedProductOfficeCountiesLasted
May 20, 6:22 PM MDTSevere Thunderstorm WarningBOUWashington38 min
May 20, 6:36 PM MDTSevere Thunderstorm WarningBOUWashington24 min
May 20, 7:01 PM MDTSevere Thunderstorm WarningBOUWashington39 min
May 21, 1:50 PM MDTSevere Thunderstorm WarningBOULogan55 min
May 21, 2:19 PM MDTSevere Thunderstorm WarningBOUWeld36 min
May 21, 3:18 PM MDTSevere Thunderstorm WarningBOUWeld42 min
May 21, 3:57 PM MDTSevere Thunderstorm WarningBOUWeld48 min
May 21, 4:22 PM MDTTornado WarningBOUWeld28 min
May 21, 4:51 PM MDTSevere Thunderstorm WarningBOULogan, Weld39 min
May 21, 5:35 PM MDTSevere Thunderstorm WarningBOULogan35 min
May 21, 5:47 PM MDTTornado WarningBOUPhillips, Sedgwick33 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.