Alert archive / Wyoming / Tornado Warnings in 2017

Tornado Warning 4, NWS Riverton, WY

June 12, 2017Johnson County, Wyoming

NWS Riverton, WY issued this tornado warning at Jun 12, 2017, 5:23 PM MDT for Johnson County, Wyoming. It was in force for 37 min. 5 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 12, 2017, 5:23 PM MDT (23:23 UTC)
Expired: Jun 12, 2017, 6:00 PM MDT
In force: 37 min
Issued by: NWS Riverton, WY
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 2.0 in

County Johnson County, WY

The radar

The Riverton/Lander radar (KRIW), 165 km from the middle of the area, began a volume at 23:25 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
Jun 12, 5:27 PM MDT	HAIL 2.5	5 Sw Kaycee, WY	GOLF BALL TO TENNIS BALL SIZED HAIL.
Jun 12, 5:34 PM MDT	HAIL 1	Kaycee, WY
Jun 12, 5:37 PM MDT	FUNNEL CLOUD	Kaycee, WY	FUNNEL CLOUD REPORTED ON THE SOUTHWEST SIDE OF KAYCEE. FUNNEL HAS DIPPED AND RETRACTED MULTIPLE TIMES.
Jun 12, 5:42 PM MDT	TORNADO	Kaycee, WY	TRAINED SPOTTER AT I-25 EXIT 249 REPORTED A TORNADO NEAR KAYCEE.
Jun 12, 5:46 PM MDT	TORNADO	2 W Kaycee, WY	DEPUTY SHERIFF REPORTED A TORNADO ABOUT 2 MILES WEST OF KAYCEE. MAY HAVE HIT A STRUCTURE.

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
Jun 12, 2:45 PM MDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Riverton, WY (KRIW), launched 12:00Z, 11.4 hours before the alert went out and 159 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: 956 m above ground
0-6 km bulk shear: 41 kt
0-1 km storm-relative helicity: 89 m²/s²
0-3 km storm-relative helicity: 173 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.1

Open this sounding in Storm Lab

The text

As transmitted.

527 
WFUS55 KRIW 122323
TORRIW
WYC019-130000-
/O.NEW.KRIW.TO.W.0004.170612T2323Z-170613T0000Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Riverton WY
523 PM MDT MON JUN 12 2017

The National Weather Service in Riverton has issued a

* Tornado Warning for...
  Southeastern Johnson County in north central Wyoming...

* Until 600 PM MDT
    
* At 522 PM MDT, a severe thunderstorm capable of producing a tornado
  was located near Kaycee, moving northeast at 35 mph.

  HAZARD...Tornado and hail up to two inches in diameter. 

  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...
  Kaycee around 535 PM MDT. 

This includes Interstate 25 between mile markers 242 and 270.
 
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.

Motorists should not take shelter under highway overpasses. If you
cannot safely drive away from the tornado, as a last resort, either
park your vehicle and stay put, or abandon your vehicle and lie down
in a low lying area and protect yourself from flying debris.

&&

LAT...LON 4351 10658 4364 10696 4400 10690 4385 10617
TIME...MOT...LOC 2322Z 218DEG 31KT 4363 10667 

TORNADO...RADAR INDICATED
HAIL...2.00IN

$$

McDonald

2 follow-up statements

138 
WWUS55 KRIW 122336
SVSRIW

Severe Weather Statement
National Weather Service Riverton WY
536 PM MDT MON JUN 12 2017

WYC019-130000-
/O.CON.KRIW.TO.W.0004.000000T0000Z-170613T0000Z/
Johnson-
536 PM MDT MON JUN 12 2017

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 600 PM MDT FOR
SOUTHEASTERN JOHNSON COUNTY...
    
At 535 PM MDT, a severe thunderstorm capable of producing a tornado
was located over Kaycee, moving north at 45 mph.

HAZARD...Tornado and tennis 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...
  Kaycee around 540 PM MDT,  Mayoworth around 545 PM MDT. 

This includes Interstate 25 between mile markers 245 and 270.
 
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.

Motorists should not take shelter under highway overpasses. If you
cannot safely drive away from the tornado, as a last resort, either
park your vehicle and stay put, or abandon your vehicle and lie down
in a low lying area and protect yourself from flying debris.

&&

LAT...LON 4357 10660 4370 10693 4400 10690 4387 10625
TIME...MOT...LOC 2335Z 190DEG 39KT 4374 10666 

TORNADO...RADAR INDICATED
HAIL...2.50IN

$$

McDonald

278 
WWUS55 KRIW 122348
SVSRIW

Severe Weather Statement
National Weather Service Riverton WY
548 PM MDT MON JUN 12 2017

WYC019-130000-
/O.CON.KRIW.TO.W.0004.000000T0000Z-170613T0000Z/
Johnson-
548 PM MDT MON JUN 12 2017

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 600 PM MDT FOR
SOUTHEASTERN JOHNSON COUNTY...
    
At 547 PM MDT, a confirmed tornado was located near Kaycee, moving 
north at 10 mph.  Another possible tornado could be north of the 
road between Kaycee and Sussex.

HAZARD...Damaging tornado and tennis ball size hail. 

SOURCE...Weather spotters confirmed tornado. 

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 tornado will be near...
  Mayoworth around 555 PM MDT. 

This includes Interstate 25 between mile markers 246 and 270.
 
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.

Motorists should not take shelter under highway overpasses. If you
cannot safely drive away from the tornado, as a last resort, either
park your vehicle and stay put, or abandon your vehicle and lie down
in a low lying area and protect yourself from flying debris.

&&

LAT...LON 4362 10655 4373 10690 4400 10690 4387 10625
TIME...MOT...LOC 2347Z 197DEG 12KT 4377 10666 

TORNADO...OBSERVED
HAIL...2.50IN

$$

McDonald

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 11, 6:20 PM MDT	Special Weather Statement	RIW		25 min
Jun 11, 6:25 PM MDT	Special Weather Statement	RIW	Natrona	35 min
Jun 11, 6:59 PM MDT	Severe Thunderstorm Warning	RIW	Natrona	32 min
Jun 11, 7:05 PM MDT	Tornado Warning	RIW	Natrona	25 min
Jun 11, 7:33 PM MDT	Special Weather Statement	RIW	Natrona	27 min
Jun 11, 7:35 PM MDT	Special Weather Statement	RIW	Fremont	40 min
Jun 11, 7:39 PM MDT	Severe Thunderstorm Warning	RIW	Natrona	51 min
Jun 11, 7:45 PM MDT	Special Weather Statement	RIW	Sublette	30 min
Jun 11, 7:57 PM MDT	Special Weather Statement	RIW	Fremont	33 min
Jun 11, 8:19 PM MDT	Special Weather Statement	RIW	Sublette	41 min
Jun 11, 8:24 PM MDT	Special Weather Statement	RIW	Hot Springs	36 min
Jun 11, 8:28 PM MDT	Special Weather Statement	RIW	Natrona	32 min
Jun 11, 8:46 PM MDT	Special Weather Statement	RIW	Hot Springs	29 min
Jun 11, 9:02 PM MDT	Special Weather Statement	RIW		28 min
Jun 11, 9:11 PM MDT	Special Weather Statement	RIW		49 min
Jun 11, 9:19 PM MDT	Special Weather Statement	RIW	Fremont	26 min
Jun 11, 9:22 PM MDT	Special Weather Statement	RIW	Fremont	23 min
Jun 11, 9:30 PM MDT	Severe Thunderstorm Warning	RIW	Fremont	45 min
Jun 11, 9:47 PM MDT	Special Weather Statement	RIW	Johnson	43 min
Jun 11, 10:01 PM MDT	Severe Thunderstorm Warning	RIW	Johnson	27 min
Jun 11, 10:17 PM MDT	Special Weather Statement	RIW		43 min
Jun 11, 10:27 PM MDT	Special Weather Statement	RIW	Washakie	48 min
Jun 11, 10:46 PM MDT	Special Weather Statement	RIW	Washakie	44 min
Jun 11, 11:22 PM MDT	Special Weather Statement	RIW	Washakie	38 min
Jun 11, 11:46 PM MDT	Special Weather Statement	RIW	Johnson	44 min
Jun 11, 11:51 PM MDT	Special Weather Statement	RIW	Hot Springs	24 min
Jun 12, 2:06 AM MDT	High Wind Warning	RIW	Fremont, Lincoln, Natrona, Sublette, Sweetwater	19 hr
Jun 12, 6:55 AM MDT	Special Weather Statement	RIW		35 min
Jun 12, 11:11 AM MDT	Areal Flood Warning	RIW	Fremont	47 hr
Jun 12, 1:29 PM MDT	Special Weather Statement	RIW	Natrona	31 min
Jun 12, 1:46 PM MDT	Special Weather Statement	RIW	Natrona	29 min
Jun 12, 2:09 PM MDT	Special Weather Statement	RIW	Natrona	36 min
Jun 12, 2:44 PM MDT	Special Weather Statement	RIW		31 min
Jun 12, 3:21 PM MDT	Special Weather Statement	RIW	Johnson	24 min
Jun 12, 3:26 PM MDT	Winter Weather Advisory	RIW	Fremont, Hot Springs, Lincoln, Park, Sublette, Teton	27 hr
Jun 12, 3:27 PM MDT	Severe Thunderstorm Warning	RIW	Big Horn, Johnson, Washakie	33 min
Jun 12, 3:30 PM MDT	Special Weather Statement	RIW		60 min
Jun 12, 3:46 PM MDT	Special Weather Statement	RIW	Teton	29 min
Jun 12, 3:55 PM MDT	Special Weather Statement	RIW	Big Horn	35 min
Jun 12, 3:58 PM MDT	Special Weather Statement	RIW	Park	32 min
Jun 12, 4:04 PM MDT	Special Weather Statement	RIW	Johnson	26 min
Jun 12, 4:06 PM MDT	Special Weather Statement	RIW		24 min
Jun 12, 4:14 PM MDT	Severe Thunderstorm Warning	RIW	Big Horn	31 min
Jun 12, 4:32 PM MDT	Special Weather Statement	RIW	Sheridan	28 min
Jun 12, 4:34 PM MDT	Special Weather Statement	RIW	Natrona	26 min
Jun 12, 4:40 PM MDT	Special Weather Statement	RIW	Park	35 min
Jun 12, 4:52 PM MDT	Severe Thunderstorm Warning	RIW	Johnson, Natrona	23 min
Jun 12, 4:53 PM MDT	Special Weather Statement	RIW	Park	22 min
Jun 12, 4:58 PM MDT	Tornado Warning	RIW	Johnson, Natrona	32 min
Jun 12, 5:03 PM MDT	Special Weather Statement	RIW	Hot Springs	27 min
Jun 12, 5:17 PM MDT	Special Weather Statement	RIW		28 min
Jun 12, 5:24 PM MDT	Severe Thunderstorm Warning	RIW	Park	36 min
Jun 12, 5:31 PM MDT	Severe Thunderstorm Warning	RIW	Park	17 min
Jun 12, 5:40 PM MDT	Tornado Warning	RIW	Big Horn, Hot Springs, Washakie	35 min
Jun 12, 5:57 PM MDT	Tornado Warning Tornado observed	RIW	Park	15 min

Nearby

Tornado Warnings in Wyoming, 2017 Every tornado warning in 2017 Tornadoes in 2017

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.