Alert archive / Wyoming / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 112, NWS Cheyenne, WY

July 11, 1998Laramie County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at Jul 11, 1998, 2:49 PM MDT for Laramie County, Wyoming. It was in force for 46 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jul 11, 1998, 2:49 PM MDT (20:49 UTC)
Expired
Jul 11, 1998, 3:35 PM MDT
In force
46 min
Issued by
NWS Cheyenne, WY
Area
Whole counties

County Laramie County, WY

The radar

The Cheyenne radar (KCYS), 20 km from the middle of the area, began a volume at 20:53 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.

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 8.8 hours before the alert went out and 202 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 1998-07-11Temperature 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 km15 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 1998-07-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 16 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1936 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
16 m²/s²
0-3 km storm-relative helicity
61 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 KCYS 112048 RRA
SVRCYS
WYC021-112135-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
249 PM MDT SAT JUL 11 1998

THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EASTERN LARAMIE COUNTY IN SOUTHEASTERN WYOMING

* UNTIL 335 PM MDT

* AT 245 PM MDT ...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 25 MILES EAST OF CHEYENNE...OR 5 MILES NORTH OF
  BURNS... MOVING EAST AT 20 MPH.

THE SEVERE THUNDERSTORM WILL REMAIN IN OPEN COUNTRY

DAMAGING WINDS IN EXCESS OF 60 MPH AND LARGE HAIL ARE LIKELY. GO
INSIDE A STURDY BUILDING AND STAY AWAY FROM WINDOWS!

LRE

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.

In the hours before

Special weather statement, Jul 11, 10:15 AM MDT, 4 hours 34 minutes before
WYZ061>070-NEZ001>003-019>021-054-055-120000-

SEVERE WEATHER OUTLOOK
NATIONAL WEATHER SERVICE CHEYENNE WY
1015 AM MDT SAT JUL 11 1998

THE SEVERE WEATHER POTENTIAL IN SOUTHEAST WYOMING AND THE NEBRASKA
PANHANDLE IS LOW TODAY.

SPOTTER ACTIVATION MAY BE REQUIRED IN THE NEBRASKA PANHANDLE.

DISCUSSION...THE ATMOSPHERE OVER SOUTHEAST WYOMING WILL DRY OUT SOME
THIS AFTERNOON WITH BETTER LOW LEVEL MOISTURE PERSISTING OVER THE
NEBRASKA PANHANDLE AS A TROUGH OF LOW PRESSURE DEVELOPS OVER THE HIGH
PLAINS EAST OF THE FRONT RANGE TODAY.

DAY TIME HEATING WILL CAUSE MODERATE INSTABILITY OVER EXTREME SOUTHEAST
WYOMING AND THE NEBRASKA PANHANDLE THIS AFTERNOON.  DIRECTIONAL WIND
SHEAR WILL BE BETTER THAN YESTERDAY AND MAY CAUSE ISOLATED SUPER
CELL THUNDERSTORMS LATER IN THE DAY...ESPECIALLY OVER THE NEBRASKA
PANHANDLE.  A 10 TO 20 PERCENT COVERAGE OF AFTERNOON THUNDERSTORMS IS
EXPECTED OVER THE AREA.

WCJIN-WYSE-WYNE
PAL
Special weather statement, Jul 11, 10:15 AM MDT, 4 hours 34 minutes before
WYZ061>070-NEZ001>003-019>021-054-055-120000-

SEVERE WEATHER OUTLOOK
NATIONAL WEATHER SERVICE CHEYENNE WY
1015 AM MDT SAT JUL 11 1998

THE SEVERE WEATHER POTENTIAL IN SOUTHEAST WYOMING AND THE NEBRASKA
PANHANDLE IS LOW TODAY.

SPOTTER ACTIVATION MAY BE REQUIRED IN THE NEBRASKA PANHANDLE.

DISCUSSION...THE ATMOSPHERE OVER SOUTHEAST WYOMING WILL DRY OUT SOME
THIS AFTERNOON WITH BETTER LOW LEVEL MOISTURE PERSISTING OVER THE
NEBRASKA PANHANDLE AS A TROUGH OF LOW PRESSURE DEVELOPS OVER THE HIGH
PLAINS EAST OF THE FRONT RANGE TODAY.

DAY TIME HEATING WILL CAUSE MODERATE INSTABILITY OVER EXTREME SOUTHEAST
WYOMING AND THE NEBRASKA PANHANDLE THIS AFTERNOON.  DIRECTIONAL WIND
SHEAR WILL BE BETTER THAN YESTERDAY AND MAY CAUSE ISOLATED SUPER
CELL THUNDERSTORMS LATER IN THE DAY...ESPECIALLY OVER THE NEBRASKA
PANHANDLE.  A 10 TO 20 PERCENT COVERAGE OF AFTERNOON THUNDERSTORMS IS
EXPECTED OVER THE AREA.

WCJIN-WYSE-WYNE
PAL

Nearby

Severe Thunderstorm Warnings in Wyoming, 1998Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.