Alert archive / Wyoming / Special Weather Statements in 2018

Special Weather Statement, NWS Cheyenne, WY

August 6, 2018Laramie County, Wyoming

NWS Cheyenne, WY issued this special weather statement at Aug 6, 2018, 12:21 AM MDT for Laramie County, Wyoming. It was in force for 24 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 6, 2018, 12:21 AM MDT (06:21 UTC)
Expired
Aug 6, 2018, 12:45 AM MDT
In force
24 min
Issued by
NWS Cheyenne, WY

County Laramie County, WY

The radar

The Cheyenne radar (KCYS), 45 km from the middle of the area, began a volume at 06:24 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 (KDEN), launched 00:00Z, 6.4 hours before the alert went out and 184 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 2018-08-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 529 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 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 2018-08-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 29 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
529 J/kg
Mixed-layer CIN
-112 J/kg
Mixed-layer LCL
2350 m above ground
0-6 km bulk shear
63 kt
0-1 km storm-relative helicity
29 m²/s²
0-3 km storm-relative helicity
117 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.9

Open this sounding in Storm Lab

The text

As transmitted.

005 
WWUS85 KCYS 060621
SPSCYS

Special Weather Statement
National Weather Service Cheyenne WY
1221 AM MDT MON AUG 6 2018
 
WYZ118-119-060645-
Central Laramie County WY-East Laramie County WY-
1221 AM MDT MON AUG 6 2018

...SIGNIFICANT WEATHER ADVISORY FOR EAST CENTRAL LARAMIE COUNTY UNTIL
1245 AM MDT...

At 1221 AM MDT, Doppler radar was tracking a strong thunderstorm 8
miles south of Gun Barrel, or 25 miles northeast of Cheyenne, moving
east at 35 mph.

Nickel size hail and wind gusts up to 50 mph will be possible with
this storm.

Locations impacted include...
Albin.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 4124 10447 4140 10447 4147 10406 4121 10406
TIME...MOT...LOC 0621Z 267DEG 29KT 4132 10437 

$$

Hammer

The office that day

Everything else NWS Cheyenne, WY issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 5, 6:01 PM MDTSpecial Weather StatementCYSNiobrara29 min
Aug 5, 6:35 PM MDTSpecial Weather StatementCYSNiobrara40 min
Aug 5, 8:32 PM MDTSpecial Weather StatementCYSLaramie43 min
Aug 6, 1:51 PM MDTSpecial Weather StatementCYSLaramie39 min
Aug 6, 1:58 PM MDTSevere Thunderstorm WarningCYSLaramie47 min
Aug 6, 2:17 PM MDTSevere Thunderstorm WarningCYSLaramie43 min
Aug 6, 2:49 PM MDTSpecial Weather StatementCYSLaramie41 min
Aug 6, 3:42 PM MDTSpecial Weather StatementCYSLaramie48 min
Aug 6, 3:59 PM MDTSpecial Weather StatementCYSConverse46 min
Aug 6, 4:42 PM MDTSevere Thunderstorm WarningCYSConverse, Niobrara, Platte33 min
Aug 6, 5:11 PM MDTSevere Thunderstorm WarningCYSGoshen, Platte16 min
Aug 5, 6:05 PM MDTSpecial Weather StatementCYSBanner25 min
Aug 5, 6:15 PM MDTSpecial Weather StatementCYSKimball45 min
Aug 5, 7:09 PM MDTSevere Thunderstorm WarningCYSCheyenne, Kimball36 min
Aug 5, 7:33 PM MDTSpecial Weather StatementCYSDawes42 min
Aug 5, 9:54 PM MDTSpecial Weather StatementCYSDawes51 min
Aug 6, 12:41 AM MDTSpecial Weather StatementCYSKimball34 min
Aug 6, 3:26 PM MDTSevere Thunderstorm WarningCYSBox Butte, Sioux49 min
Aug 6, 3:40 PM MDTSpecial Weather StatementCYSBox Butte50 min
Aug 6, 3:56 PM MDTSevere Thunderstorm WarningCYSBox Butte, Morrill49 min
Aug 6, 4:33 PM MDTSevere Thunderstorm WarningCYSMorrill42 min
Aug 6, 5:08 PM MDTSevere Thunderstorm WarningCYSMorrill26 min

Nearby

Special Weather Statements in Wyoming, 2018Every special weather statement in 2018

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.