Alert archive / Wyoming / Tornado Warnings in 2018

Tornado Warning 8, NWS Cheyenne, WY

May 27, 2018Goshen County, Laramie County, Platte County, Wyoming

NWS Cheyenne, WY issued this tornado warning at May 27, 2018, 4:15 PM MDT for Goshen County, Laramie County, Platte County, Wyoming. It was in force for 45 min. 3 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: May 27, 2018, 4:15 PM MDT (22:15 UTC)
Expired: May 27, 2018, 5:00 PM MDT
In force: 45 min
Issued by: NWS Cheyenne, WY
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 1.75 in

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

The radar

The Cheyenne radar (KCYS), 33 km from the middle of the area, began a volume at 22:19 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 27, 4:15 PM MDT	TORNADO	15 N Cheyenne, WY	TORNADO MOVING TOWARDS I-25 BETWEEN MM 25 AND 35.
May 27, 4:21 PM MDT	TORNADO	19 Nnw Cheyenne, WY	A VEHICLE WAS DAMAGED NEAR THE WHITAKER EXIT ALONG INTERSTATE 25 WITH INDICATION OF TORNADIC ROTATION. WITHOUT A DAMAGE INDICATOR, THIS PORTION OF THE TORNADO WAS RATED EF-UNKNOWN.
May 27, 4:30 PM MDT	FUNNEL CLOUD	30 N Cheyenne, WY	NEAR MILE MARKER 40

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 27, 12:05 PM MDT	Severe Thunderstorm Watch	SPC	9 hr

The nearest sounding before it

Denver, CO (KDEN), launched 12:00Z, 10.3 hours before the alert went out and 221 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 4365 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 20 m²/s²
0-3 km storm-relative helicity: 105 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

727 
WFUS55 KCYS 272215
TORCYS
WYC015-021-031-272300-
/O.NEW.KCYS.TO.W.0008.180527T2215Z-180527T2300Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Cheyenne WY
415 PM MDT SUN MAY 27 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 500 PM MDT
    
* At 414 PM MDT, a severe thunderstorm capable of producing a tornado
  was located near Whitaker, or 17 miles northwest of Cheyenne,
  moving northeast at 45 mph.

  HAZARD...Tornado and golf ball 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 dangerous storm will be near...
  Whitaker around 420 PM MDT.

This includes Interstate 25 in Wyoming between mile markers 24 and
44.
 
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.

Heavy rainfall may hide this tornado. Do not wait to see or hear the
tornado. TAKE COVER NOW!

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
Cheyenne.

&&

LAT...LON 4128 10492 4139 10510 4172 10475 4155 10445
TIME...MOT...LOC 2214Z 222DEG 39KT 4138 10493 

TORNADO...RADAR INDICATED
HAIL...1.75IN

$$

Claycomb

2 follow-up statements

647 
WWUS55 KCYS 272239
SVSCYS

Severe Weather Statement
National Weather Service Cheyenne WY
439 PM MDT SUN MAY 27 2018

WYC015-021-031-272300-
/O.CON.KCYS.TO.W.0008.000000T0000Z-180527T2300Z/
Goshen WY-Laramie WY-Platte WY-
439 PM MDT SUN MAY 27 2018

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 500 PM MDT FOR
SOUTHWESTERN GOSHEN...NORTH CENTRAL LARAMIE AND SOUTHEASTERN PLATTE
COUNTIES...
    
At 438 PM MDT, a confirmed large and extremely dangerous tornado was
located near Whitaker, or 22 miles north of Cheyenne, moving
northeast at 35 mph. 

This is a PARTICULARLY DANGEROUS SITUATION. TAKE COVER NOW!

HAZARD...Damaging tornado.

SOURCE...Weather spotters confirmed tornado. A tornado has been 
         reported 2 miles east og highway 25 near mile marker 32 at 
         439 PM.

IMPACT...You are in a life-threatening situation. Flying debris may 
         be deadly to those caught without shelter. Mobile homes 
         will be destroyed. Considerable damage to homes, 
         businesses, and vehicles is likely and complete destruction 
         is possible.

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

This includes Interstate 25 in Wyoming between mile markers 29 and
37.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

To repeat, a large, extremely dangerous and potentially deadly
tornado is on the ground. To protect your life, 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.

Heavy rainfall may hide this tornado. Do not wait to see or hear the
tornado. TAKE COVER NOW!

If a tornado or other severe weather is spotted, report it to the
National Weather Service or your local nearest law enforcement agency
who will send your report. This act may save lives of others in the
path of dangerous weather.

&&

LAT...LON 4135 10480 4145 10495 4172 10475 4155 10445
TIME...MOT...LOC 2238Z 222DEG 31KT 4147 10481 

TORNADO...OBSERVED
TORNADO DAMAGE THREAT...CONSIDERABLE
HAIL...1.75IN

$$

Claycomb

476 
WWUS55 KCYS 272252
SVSCYS

Severe Weather Statement
National Weather Service Cheyenne WY
452 PM MDT SUN MAY 27 2018

WYC031-272301-
/O.CAN.KCYS.TO.W.0008.000000T0000Z-180527T2300Z/
Platte WY-
452 PM MDT SUN MAY 27 2018

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

A severe thunderstorm watch remains in effect until 800 PM MDT for
southeastern Wyoming.

LAT...LON 4139 10483 4147 10490 4165 10480 4150 10453
      4148 10457
TIME...MOT...LOC 2251Z 220DEG 32KT 4150 10479 

$$

WYC015-021-272300-
/O.CON.KCYS.TO.W.0008.000000T0000Z-180527T2300Z/
Goshen WY-Laramie WY-
452 PM MDT SUN MAY 27 2018

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 500 PM MDT FOR
SOUTHWESTERN GOSHEN AND NORTH CENTRAL LARAMIE COUNTIES...
    
At 451 PM MDT, a confirmed large and extremely dangerous tornado was
located 7 miles northeast of Whitaker, or 24 miles north of Cheyenne,
moving northeast at 35 mph.

This is a PARTICULARLY DANGEROUS SITUATION. TAKE COVER NOW!

HAZARD...Damaging tornado.

SOURCE...Weather spotters confirmed tornado.

IMPACT...You are in a life-threatening situation. Flying debris may 
         be deadly to those caught without shelter. Mobile homes 
         will be destroyed. Considerable damage to homes, 
         businesses, and vehicles is likely and complete destruction 
         is possible.

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
34.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

To repeat, a large, extremely dangerous and potentially deadly
tornado is on the ground. To protect your life, 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.

Heavy rainfall may hide this tornado. Do not wait to see or hear the
tornado. TAKE COVER NOW!

If a tornado or other severe weather is spotted, report it to the
National Weather Service or your local nearest law enforcement agency
who will send your report. This act may save lives of others in the
path of dangerous weather.

&&

LAT...LON 4139 10483 4147 10490 4165 10480 4150 10453
      4148 10457
TIME...MOT...LOC 2251Z 220DEG 32KT 4150 10479 

TORNADO...OBSERVED
TORNADO DAMAGE THREAT...CONSIDERABLE
HAIL...1.75IN

$$

Claycomb

The office that day

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

Issued	Product	Office	Counties	Lasted
May 26, 6:48 PM MDT	Special Weather Statement	CYS		42 min
May 26, 7:37 PM MDT	Special Weather Statement	CYS	Carbon	38 min
May 26, 9:05 PM MDT	Special Weather Statement	CYS	Converse	40 min
May 27, 2:58 AM MDT	Flash Flood Watch	CYS	Albany, Converse, Goshen, Laramie, Niobrara, Platte	21 hr
May 27, 12:59 PM MDT	Severe Thunderstorm Warning	CYS	Albany	23 min
May 27, 2:15 PM MDT	Severe Thunderstorm Warning	CYS	Albany, Laramie	31 min
May 27, 2:43 PM MDT	Tornado Warning Tornado observed	CYS	Albany, Laramie	32 min
May 27, 2:56 PM MDT	Severe Thunderstorm Warning	CYS	Albany	30 min
May 27, 3:08 PM MDT	Tornado Warning Tornado observed	CYS	Albany, Laramie	8 min
May 27, 3:18 PM MDT	Special Weather Statement	CYS		42 min
May 27, 3:21 PM MDT	Tornado Warning Tornado observed	CYS	Laramie	24 min
May 27, 3:28 PM MDT	Severe Thunderstorm Warning	CYS	Albany, Converse, Platte	47 min
May 27, 3:33 PM MDT	Special Weather Statement	CYS	Albany	42 min
May 27, 3:41 PM MDT	Special Weather Statement	CYS		49 min
May 27, 3:42 PM MDT	Tornado Warning Tornado observed	CYS	Laramie	48 min
May 27, 3:48 PM MDT	Areal Flood Advisory	CYS	Albany, Laramie	3 hr
May 27, 4:05 PM MDT	Tornado Warning Tornado observed	CYS	Albany, Converse, Platte	40 min
May 27, 4:08 PM MDT	Special Weather Statement	CYS	Laramie	52 min
May 27, 4:17 PM MDT	Severe Thunderstorm Warning	CYS	Laramie	43 min
May 27, 4:29 PM MDT	Tornado Warning	CYS	Albany, Converse, Platte	20 min
May 27, 4:32 PM MDT	Severe Thunderstorm Warning	CYS	Converse	29 min
May 27, 4:42 PM MDT	Areal Flood Advisory	CYS	Albany, Converse, Platte	3 hr
May 27, 4:47 PM MDT	Flash Flood Warning	CYS	Albany, Laramie	3 hr
May 27, 5:00 PM MDT	Tornado Warning	CYS	Laramie	19 min
May 27, 5:12 PM MDT	Special Weather Statement	CYS	Converse	48 min
May 27, 5:13 PM MDT	Special Weather Statement	CYS	Platte	47 min
May 27, 5:42 PM MDT	Special Weather Statement	CYS	Platte	48 min

Nearby

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