Alert archive / Montana / Tornado Warnings in 2011

Tornado Warning 13, NWS Billings, MT

July 11, 2011Big Horn County, Montana; Sheridan County, Wyoming

NWS Billings, MT issued this tornado warning at Jul 11, 2011, 5:00 PM MDT for Big Horn County, Montana; Sheridan County, Wyoming. It was in force for 30 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: Jul 11, 2011, 5:00 PM MDT (23:00 UTC)
Expired: Jul 11, 2011, 5:30 PM MDT
In force: 30 min
Issued by: NWS Billings, MT
Area: Storm-based polygon

Counties Big Horn County, MT, Sheridan County, WY

The radar

The Billings radar (KBLX), 123 km from the middle of the area, began a volume at 23:04 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.

The nearest sounding before it

Riverton, WY (KRIW), launched 12:00Z, 11.0 hours before the alert went out and 215 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: 2821 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: -14 m²/s²
0-3 km storm-relative helicity: 42 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

760 
WFUS55 KBYZ 112300
TORBYZ
MTC003-WYC033-112330-
/O.NEW.KBYZ.TO.W.0013.110711T2300Z-110711T2330Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE BILLINGS MT
500 PM MDT MON JUL 11 2011

THE NATIONAL WEATHER SERVICE IN BILLINGS HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHWESTERN SHERIDAN COUNTY IN NORTH CENTRAL WYOMING...
  SOUTH CENTRAL BIG HORN COUNTY IN SOUTH CENTRAL MONTANA...

* UNTIL 530 PM MDT.

* AT 500 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO OVER EXTREME
  NORTHWESTERN SHERIDAN COUNTY...OR 30 MILES EAST OF LOVELL...MOVING
  SOUTHEAST AT 15 MPH.

* THE TORNADO WILL BE NEAR...
  RURAL NORTHWESTERN SHERIDAN COUNTY AT 510 PM MDT

THIS DOES NOT INCLUDE THE CITY OF SHERIDAN. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER IN A NEARBY REINFORCED
BUILDING. AS A LAST RESORT...SEEK SHELTER IN A CULVERT...DITCH OR LOW
SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

THE SAFEST PLACE TO BE DURING A TORNADO IS IN A BASEMENT. GET UNDER A
WORKBENCH OR OTHER PIECE OF STURDY FURNITURE. IF NO BASEMENT IS
AVAILABLE...SEEK SHELTER ON THE LOWEST FLOOR OF THE BUILDING IN AN
INTERIOR HALLWAY OR ROOM SUCH AS A CLOSET. USE BLANKETS OR PILLOWS TO
COVER YOUR BODY AND ALWAYS STAY AWAY FROM WINDOWS.

IF IN MOBILE HOMES OR VEHICLES...EVACUATE THEM AND GET INSIDE A
SUBSTANTIAL SHELTER. IF NO SHELTER IS AVAILABLE...LIE FLAT IN THE
NEAREST DITCH OR OTHER LOW SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

&&

LAT...LON 4480 10767 4499 10792 4508 10787 4502 10751
TIME...MOT...LOC 2259Z 284DEG 10KT 4498 10781

$$

1 follow-up statement

747 
WWUS55 KBYZ 112313
SVSBYZ

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BILLINGS MT
513 PM MDT MON JUL 11 2011

MTC003-WYC033-112330-
/O.CON.KBYZ.TO.W.0013.000000T0000Z-110711T2330Z/
BIG HORN MT-SHERIDAN WY-
513 PM MDT MON JUL 11 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 530 PM MDT FOR
NORTHWESTERN SHERIDAN AND SOUTH CENTRAL BIG HORN COUNTIES...

AT 512 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A TORNADO.  THIS TORNADO WAS LOCATED OVER EXTREME
NORTHWESTERN SHERIDAN COUNTY...OR 32 MILES EAST OF LOVELL...MOVING
SOUTHEAST AT 15 MPH.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IN ADDITION TO THE TORNADO...THIS STORM IS CAPABLE OF PRODUCING GOLF 
BALL SIZE HAIL AND DESTRUCTIVE STRAIGHT LINE WINDS.

THE SAFEST PLACE TO BE DURING A TORNADO IS IN A BASEMENT. GET UNDER A
WORKBENCH OR OTHER PIECE OF STURDY FURNITURE. IF NO BASEMENT IS
AVAILABLE...SEEK SHELTER ON THE LOWEST FLOOR OF THE BUILDING IN AN
INTERIOR HALLWAY OR ROOM SUCH AS A CLOSET. USE BLANKETS OR PILLOWS TO
COVER YOUR BODY AND ALWAYS STAY AWAY FROM WINDOWS.

&&

LAT...LON 4480 10767 4499 10792 4508 10787 4502 10751
TIME...MOT...LOC 2311Z 284DEG 10KT 4497 10776

$$

The office that day

Everything else NWS Billings, MT issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 11, 12:36 PM MDT	Special Weather Statement	BYZ	Wheatland	39 min
Jul 11, 1:17 PM MDT	Special Weather Statement	BYZ	Sweet Grass	43 min
Jul 11, 2:00 PM MDT	Special Weather Statement	BYZ	Stillwater	45 min
Jul 11, 2:36 PM MDT	Special Weather Statement	BYZ	Carbon	54 min
Jul 11, 3:04 PM MDT	Special Weather Statement	BYZ	Stillwater	56 min
Jul 11, 3:44 PM MDT	Special Weather Statement	BYZ	Big Horn	61 min
Jul 11, 5:25 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn	65 min
Jul 11, 5:38 PM MDT	Special Weather Statement	BYZ		67 min
Jul 11, 4:30 PM MDT	Special Weather Statement	BYZ	Big Horn	60 min

Nearby

Tornado Warnings in Montana, 2011 Tornado Warnings in Wyoming, 2011 Every tornado warning in 2011 Tornadoes in 2011

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.