Alert archive / Wyoming / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 13, NWS Cheyenne, WY

May 11, 2018Carbon County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at May 11, 2018, 5:59 PM MDT for Carbon County, Wyoming. It was in force for 46 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: May 11, 2018, 5:59 PM MDT (23:59 UTC)
Expired: May 11, 2018, 6:45 PM MDT
In force: 46 min
Issued by: NWS Cheyenne, WY
Area: Storm-based polygon
Hail: 1.75 in
Wind: 60.0 mph

County Carbon County, WY

The radar

The Riverton/Lander radar (KRIW), 188 km from the middle of the area, began a volume at 00:04 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 11, 6:15 PM MDT	HAIL 1.75	5 E Sinclair, WY	HAIL CAUSED DAMAGE TO HIS CAR. LARGE DENTS

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
May 11, 2:02 PM MDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Riverton, WY (KRIW), launched 12:00Z, 12.0 hours before the alert went out and 185 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: 5 J/kg
Mixed-layer CIN: -161 J/kg
Mixed-layer LCL: 1377 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 7 m²/s²
0-3 km storm-relative helicity: -9 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

518 
WUUS55 KCYS 112359
SVRCYS
WYC007-120045-
/O.NEW.KCYS.SV.W.0013.180511T2359Z-180512T0045Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Cheyenne WY
559 PM MDT FRI MAY 11 2018

The National Weather Service in Cheyenne has issued a

* Severe Thunderstorm Warning for...
  Central Carbon County in south central Wyoming...

* Until 645 PM MDT

* At 557 PM MDT, a severe thunderstorm was located near Sinclair, or
  11 miles east of Rawlins, moving east at 25 mph.

  HAZARD...Golf ball size hail and 60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...People and animals outdoors will be injured. Expect hail 
           damage to vehicles especially on Interstate 80. Roofs, 
           siding, and windows will also see damage. Expect wind 
           damage to roofs, siding, and trees.

* Locations impacted include...
  Sinclair.

This includes Interstate 80 in Wyoming between mile markers 219 and
243.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

This is a dangerous storm. Prepare immediately for large destructive
hail capable of producing significant damage. People outside should
move to shelter inside a strong building,  and stay away from
windows.

&&

LAT...LON 4168 10715 4197 10712 4199 10667 4167 10668
TIME...MOT...LOC 2357Z 271DEG 21KT 4178 10701 

HAIL...1.75IN
WIND...60MPH
 
$$

Cox

2 follow-up statements

888 
WWUS55 KCYS 120016
SVSCYS

Severe Weather Statement
National Weather Service Cheyenne WY
616 PM MDT FRI MAY 11 2018

WYC007-120045-
/O.CON.KCYS.SV.W.0013.000000T0000Z-180512T0045Z/
Carbon WY-
616 PM MDT FRI MAY 11 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 645 PM MDT
FOR CENTRAL CARBON COUNTY...

At 614 PM MDT, a severe thunderstorm was located 12 miles east of 
Sinclair near mile marker 230 on Interstate 80, or 18 miles east of 
Rawlins. This storm was moving east at 25 mph.

HAZARD...Golf ball size hail and 60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...People and animals outdoors will be injured. Expect hail 
         damage to vehicles on Interstate 80. Expect wind damage to 
         roofs, siding, and trees.

This severe thunderstorm will remain over mainly rural areas of
central Carbon County.

This includes Interstate 80 in Wyoming between mile markers 224 and
243.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

This is a dangerous storm. Prepare immediately for large destructive
hail capable of producing significant damage. People outside should
move to a shelter, inside a strong building and away from windows.

&&

LAT...LON 4168 10707 4197 10704 4199 10667 4167 10668
TIME...MOT...LOC 0014Z 271DEG 21KT 4178 10687 

HAIL...1.75IN
WIND...60MPH
 
$$

Cox

518 
WWUS55 KCYS 120026
SVSCYS

Severe Weather Statement
National Weather Service Cheyenne WY
626 PM MDT FRI MAY 11 2018

WYC007-120045-
/O.CON.KCYS.SV.W.0013.000000T0000Z-180512T0045Z/
Carbon WY-
626 PM MDT FRI MAY 11 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 645 PM MDT
FOR NORTHEASTERN CARBON COUNTY...

At 625 PM MDT, a severe thunderstorm was located 13 miles east of 
Sinclair, or 19 miles east of Rawlins, moving east at 20 mph. This 
storm is now just north of Interstate 80. 

HAZARD...Golf ball size hail and 60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...People and animals outdoors will be injured. Expect hail 
         damage to roofs, siding, windows, and vehicles. Expect wind 
         damage to roofs, siding, and trees.

This severe thunderstorm will remain over mainly rural areas of
northeastern Carbon County.

This includes Interstate 80 in Wyoming between mile markers 226 and
241.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

This is a dangerous storm. Prepare immediately for large destructive
hail capable of producing significant damage. People outside should
move to a shelter, inside a strong building and away from windows.

&&

LAT...LON 4173 10701 4197 10704 4199 10669 4170 10671
TIME...MOT...LOC 0025Z 268DEG 18KT 4179 10685 

HAIL...1.75IN
WIND...60MPH
 
$$

Cox

The office that day

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

Issued	Product	Office	Counties	Lasted
May 11, 1:57 PM MDT	Special Weather Statement	CYS	Albany	48 min
May 11, 2:11 PM MDT	Severe Thunderstorm Warning	CYS	Albany, Platte	37 min
May 11, 2:38 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Platte	36 min
May 11, 3:32 PM MDT	Special Weather Statement	CYS	Laramie	43 min
May 11, 3:36 PM MDT	Severe Thunderstorm Warning	CYS	Laramie, Platte	24 min
May 11, 3:44 PM MDT	Special Weather Statement	CYS	Laramie	46 min
May 11, 4:20 PM MDT	Special Weather Statement	CYS	Laramie	40 min
May 11, 4:22 PM MDT	Special Weather Statement	CYS	Laramie	38 min
May 11, 4:31 PM MDT	Special Weather Statement	CYS	Carbon	59 min
May 11, 4:33 PM MDT	Severe Thunderstorm Warning	CYS	Laramie, Platte	24 min
May 11, 4:34 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Laramie	26 min
May 11, 4:49 PM MDT	Severe Thunderstorm Warning	CYS	Carbon	41 min
May 11, 5:27 PM MDT	Severe Thunderstorm Warning	CYS	Carbon	33 min
May 11, 5:28 PM MDT	Dense Fog Advisory	CYS	Albany, Laramie, Platte	13 hr

Nearby

Severe Thunderstorm Warnings in Wyoming, 2018 Every severe thunderstorm warning 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.