Alert archive / Wyoming / Tornado Warnings in 2018

Tornado Warning 18, NWS Cheyenne, WY

June 19, 2018Goshen County, Laramie County, Platte County, Wyoming

NWS Cheyenne, WY issued this tornado warning at Jun 19, 2018, 2:42 PM MDT for Goshen County, Laramie County, Platte County, Wyoming. It was in force for 48 min. 2 reports 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
Jun 19, 2018, 2:42 PM MDT (20:42 UTC)
Expired
Jun 19, 2018, 3:30 PM MDT
In force
48 min
Issued by
NWS Cheyenne, WY
Area
Storm-based polygon
Tornado
Radar indicated
Hail
1.0 in

Counties Goshen County, WY, Laramie County, WY, Platte County, WY

The radar

The Cheyenne radar (KCYS), 44 km from the middle of the area, began a volume at 20:41 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
Jun 19, 2:54 PM MDTTORNADO25 N Cheyenne, WYPUBLIC REPORT OF A SMALL TORNADO 1/2 MILE TO THE WEST OF INTERSTATE 25.
Jun 19, 2:54 PM MDTTORNADO25 N Cheyenne, WYPUBLIC REPORT OF A SMALL TORNADO 1/2 MILE TO THE WEST OF INTERSTATE 25 AT MILE MARKER 34.

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

The nearest sounding before it

Denver, CO (KDEN), launched 12:00Z, 8.7 hours before the alert went out and 228 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 2018-06-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 30 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 12:00Z on 2018-06-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 70 square meters per square second.19395878Sfc1 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
30 J/kg
Mixed-layer CIN
-220 J/kg
Mixed-layer LCL
836 m above ground
0-6 km bulk shear
53 kt
0-1 km storm-relative helicity
70 m²/s²
0-3 km storm-relative helicity
73 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

410 
WFUS55 KCYS 192042
TORCYS
WYC015-021-031-192130-
/O.NEW.KCYS.TO.W.0018.180619T2042Z-180619T2130Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Cheyenne WY
242 PM MDT TUE JUN 19 2018

The National Weather Service in Cheyenne has issued a

* Tornado Warning for...
  Southwestern Goshen County in southeastern Wyoming...
  Northwestern Laramie County in southeastern Wyoming...
  Southeastern Platte County in southeastern Wyoming...

* Until 330 PM MDT.
    
* At 242 PM MDT, a severe thunderstorm capable of producing a tornado
  was located 10 miles north of Whitaker, or 28 miles north of
  Cheyenne, moving east at 35 mph.

  HAZARD...Tornado and quarter size hail.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* This tornadic thunderstorm will remain over mainly rural areas of
  southwestern Goshen...northwestern Laramie and southeastern Platte
  Counties.

This includes Interstate 25 in Wyoming between mile markers 33 and
51.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4147 10502 4171 10495 4170 10439 4140 10449
TIME...MOT...LOC 2042Z 277DEG 29KT 4155 10491 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

Cox
3 follow-up statements
778 
WWUS55 KCYS 192059
SVSCYS

Severe Weather Statement
National Weather Service Cheyenne WY
259 PM MDT TUE JUN 19 2018

WYC031-192107-
/O.CAN.KCYS.TO.W.0018.000000T0000Z-180619T2130Z/
Platte WY-
259 PM MDT TUE JUN 19 2018

...THE TORNADO WARNING FOR SOUTHEASTERN PLATTE COUNTY IS CANCELLED...
    
The tornadic thunderstorm which prompted the warning has weakened 
over the warned area. Therefore, the warning has been cancelled.

LAT...LON 4146 10497 4165 10490 4165 10441 4140 10449
TIME...MOT...LOC 2057Z 277DEG 29KT 4154 10480 

$$

WYC015-021-192130-
/O.CON.KCYS.TO.W.0018.000000T0000Z-180619T2130Z/
Goshen WY-Laramie WY-
259 PM MDT TUE JUN 19 2018

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 330 PM MDT FOR
SOUTHWESTERN GOSHEN AND NORTH CENTRAL LARAMIE COUNTIES...
    
At 257 PM MDT, a confirmed tornado was located 9 miles northeast of
Whitaker, or 27 miles north of Cheyenne, moving east at 35 mph.

HAZARD...Damaging tornado and quarter size hail.

SOURCE...Public confirmed tornado near mile marker 40.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This tornadic thunderstorm will remain over mainly rural areas of
southwestern Goshen and north central Laramie Counties.

This includes Interstate 25 in Wyoming between mile markers 33 and
46.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

To repeat, a tornado is on the ground. TAKE COVER NOW! Move to a
basement or an interior room on the lowest floor of a sturdy
building. Avoid windows. If you are outdoors, in a mobile home, or in
a vehicle, move to the closest substantial shelter and protect
yourself from flying debris.

&&

LAT...LON 4146 10497 4165 10490 4165 10441 4140 10449
TIME...MOT...LOC 2057Z 277DEG 29KT 4154 10480 

TORNADO...OBSERVED
HAIL...1.00IN

$$

Cox
812 
WWUS55 KCYS 192111
SVSCYS

Severe Weather Statement
National Weather Service Cheyenne WY
311 PM MDT TUE JUN 19 2018

WYC015-021-192130-
/O.CON.KCYS.TO.W.0018.000000T0000Z-180619T2130Z/
Goshen WY-Laramie WY-
311 PM MDT TUE JUN 19 2018

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 330 PM MDT FOR
SOUTHWESTERN GOSHEN AND NORTH CENTRAL LARAMIE COUNTIES...
    
At 309 PM MDT, a severe thunderstorm capable of producing a tornado
was located 13 miles northeast of Whitaker, or 27 miles north of
Cheyenne, moving east at 35 mph.

HAZARD...Tornado and quarter size hail.

SOURCE...Radar indicated rotation.  

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This tornadic thunderstorm will remain over mainly rural areas of 
southwestern Goshen and north central Laramie Counties. The rotation 
on this storm has weakened, but could spin up quickly.

This includes Interstate 25 in Wyoming between mile markers 33 and 
37. This warning does not include the city of Cheyenne.
  
PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4146 10493 4165 10482 4165 10441 4140 10449
TIME...MOT...LOC 2109Z 277DEG 29KT 4153 10467 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

Cox
484 
WWUS55 KCYS 192124
SVSCYS

Severe Weather Statement
National Weather Service Cheyenne WY
324 PM MDT TUE JUN 19 2018

WYC015-021-192132-
/O.EXP.KCYS.TO.W.0018.000000T0000Z-180619T2130Z/
Goshen WY-Laramie WY-
324 PM MDT TUE JUN 19 2018

...THE TORNADO WARNING FOR SOUTHWESTERN GOSHEN AND NORTH CENTRAL
LARAMIE COUNTIES WILL EXPIRE AT 330 PM MDT...
    
The tornado threat has diminished and the Tornado Warning has been 
allowed to expire. However, large hail and damaging winds remain 
likely and a Severe Thunderstorm Warning remains in effect for the 
area. However small hail, gusty winds and heavy rain are still 
possible with this thunderstorm.

Remember, a Severe Thunderstorm Warning still remains in effect for
northern Larmie county. 

LAT...LON 4146 10493 4165 10482 4165 10441 4140 10449
TIME...MOT...LOC 2122Z 277DEG 29KT 4152 10456 

$$

Cox

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 18, 6:33 PM MDTSpecial Weather StatementCYSGoshen42 min
Jun 18, 6:44 PM MDTSpecial Weather StatementCYSConverse46 min
Jun 18, 6:48 PM MDTSevere Thunderstorm WarningCYSGoshen, Laramie42 min
Jun 18, 7:30 PM MDTSpecial Weather StatementCYSLaramie45 min
Jun 19, 4:20 AM MDTSpecial Weather StatementCYSNiobrara40 min
Jun 19, 5:22 AM MDTSpecial Weather StatementCYS38 min
Jun 19, 7:17 AM MDTSpecial Weather StatementCYS43 min
Jun 19, 7:40 AM MDTSpecial Weather StatementCYSNiobrara35 min
Jun 19, 7:44 AM MDTSpecial Weather StatementCYSConverse46 min
Jun 19, 8:14 AM MDTSpecial Weather StatementCYSNiobrara46 min
Jun 19, 8:27 AM MDTSpecial Weather StatementCYSConverse48 min
Jun 19, 9:17 AM MDTSpecial Weather StatementCYSNiobrara43 min
Jun 19, 11:42 AM MDTSpecial Weather StatementCYS48 min
Jun 19, 12:00 PM MDTSevere Thunderstorm WarningCYSCarbon45 min
Jun 19, 12:52 PM MDTSpecial Weather StatementCYSAlbany53 min
Jun 19, 12:58 PM MDTSpecial Weather StatementCYS47 min
Jun 19, 1:03 PM MDTSpecial Weather StatementCYSLaramie42 min
Jun 19, 1:10 PM MDTSpecial Weather StatementCYSPlatte50 min
Jun 19, 1:24 PM MDTSevere Thunderstorm WarningCYSLaramie, Platte34 min
Jun 19, 1:38 PM MDTTornado WarningCYSAlbany37 min
Jun 19, 2:01 PM MDTTornado WarningCYSAlbany, Laramie, Platte44 min
Jun 19, 2:30 PM MDTTornado Warning Tornado observedCYSPlatte17 min
Jun 19, 3:20 PM MDTSevere Thunderstorm WarningCYSLaramie40 min
Jun 19, 3:29 PM MDTSevere Thunderstorm WarningCYSLaramie61 min
Jun 19, 3:41 PM MDTSevere Thunderstorm WarningCYSLaramie49 min
Jun 19, 4:07 PM MDTSevere Thunderstorm WarningCYSLaramie38 min
Jun 19, 4:38 PM MDTSevere Thunderstorm WarningCYSLaramie52 min

Nearby

Tornado Warnings in Wyoming, 2018Every tornado warning in 2018Tornadoes 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.