Alert archive / Wyoming / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 76, NWS Cheyenne, WY

July 5, 2012Albany County, Converse County, Platte County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at Jul 5, 2012, 4:47 PM MDT for Albany County, Converse County, Platte County, Wyoming. It was in force for 43 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: Jul 5, 2012, 4:47 PM MDT (22:47 UTC)
Expired: Jul 5, 2012, 5:30 PM MDT
In force: 43 min
Issued by: NWS Cheyenne, WY
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Albany County, WY, Converse County, WY, Platte County, WY

The radar

The Cheyenne radar (KCYS), 144 km from the middle of the area, began a volume at 22:50 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
Jul 5, 5:22 PM MDT	HAIL 0.75	24 Nw Wheatland, WY	PICKED UP 0.25 INCHES IN ABOUT 5 MINUTES.

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
Jul 5, 4:10 PM MDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Riverton, WY (KRIW), launched 12:00Z, 10.8 hours before the alert went out and 258 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: 34 J/kg
Mixed-layer CIN: -190 J/kg
Mixed-layer LCL: 2588 m above ground
0-6 km bulk shear: 36 kt
0-1 km storm-relative helicity: 73 m²/s²
0-3 km storm-relative helicity: 102 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.

160 
WUUS55 KCYS 052247
SVRCYS
WYC001-009-031-052330-
/O.NEW.KCYS.SV.W.0076.120705T2247Z-120705T2330Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
447 PM MDT THU JUL 5 2012

THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHEASTERN ALBANY COUNTY IN SOUTHEAST WYOMING...
  SOUTH CENTRAL CONVERSE COUNTY IN EAST CENTRAL WYOMING...
  NORTHWESTERN PLATTE COUNTY IN SOUTHEAST WYOMING...

* UNTIL 530 PM MDT

* AT 445 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR
  FRIEND PARK CAMPGROUND...OR 29 MILES NORTHWEST OF WHEATLAND...AND
  MOVING NORTHEAST AT 20 MPH.

* LOCATIONS IMPACTED INCLUDE...
  NORTHERN PORTIONS OF THE ARAPAHO FIRE...LARAMIE PEAK...HARRIS      
  PARK...ESTERBROOK AND ESTERBROOK CAMPGROUND.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF YOU ARE IN THE PATH OF THIS STORM...PREPARE IMMEDIATELY FOR LARGE
HAIL AND DAMAGING WINDS. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING AND AWAY FROM WINDOWS.

TORRENTIAL RAINFALL IS ALSO OCCURRING WITH THIS STORM...AND MAY LEAD
TO FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED
ROADWAYS.

&&

LAT...LON 4255 10537 4237 10506 4214 10548 4224 10565
TIME...MOT...LOC 2247Z 218DEG 18KT 4224 10546
WIND...HAIL 60MPH 1.00IN

$$

MAZUR

2 follow-up statements

962 
WWUS55 KCYS 052306
SVSCYS

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
506 PM MDT THU JUL 5 2012

WYC001-009-031-052330-
/O.CON.KCYS.SV.W.0076.000000T0000Z-120705T2330Z/
ALBANY WY-CONVERSE WY-PLATTE WY-
506 PM MDT THU JUL 5 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR NORTHWESTERN
PLATTE...EXTREME SOUTH CENTRAL CONVERSE AND NORTHEASTERN ALBANY
COUNTIES UNTIL 530 PM MDT...

AT 503 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR
LARAMIE PEAK...OR 28 MILES NORTHWEST OF WHEATLAND...MOVING NORTHEAST
AT 20 MPH.

LOCATIONS IMPACTED INCLUDE...
  NORTHERN PORTIONS OF THE ARAPAHO FIRE...HARRIS PARK...ESTERBROOK   
  AND ESTERBROOK CAMPGROUND.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

PREPARE IMMEDIATELY FOR LARGE HAIL AND DAMAGING WINDS IF YOU ARE IN
THE PATH OF THIS STORM. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING AND AWAY FROM WINDOWS.

TORRENTIAL RAINFALL IS ALSO OCCURRING WITH THIS STORM...AND MAY LEAD
TO FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED
ROADWAYS.

&&

LAT...LON 4234 10549 4248 10525 4237 10506 4216 10545
TIME...MOT...LOC 2306Z 218DEG 18KT 4231 10538
WIND...HAIL 60MPH 1.00IN

$$

MAZUR

661 
WWUS55 KCYS 052324
SVSCYS

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
524 PM MDT THU JUL 5 2012

WYC001-009-031-052334-
/O.EXP.KCYS.SV.W.0076.000000T0000Z-120705T2330Z/
ALBANY WY-CONVERSE WY-PLATTE WY-
524 PM MDT THU JUL 5 2012

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN PLATTE...EXTREME
SOUTH CENTRAL CONVERSE AND NORTHEASTERN ALBANY COUNTIES WILL EXPIRE
AT 530 PM MDT...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR PROPERTY.
 HOWEVER SMALL HAIL...GUSTY WINDS AND HEAVY RAIN ARE STILL POSSIBLE
WITH THIS THUNDERSTORM.

LAT...LON 4234 10549 4248 10525 4237 10506 4216 10545
TIME...MOT...LOC 2324Z 218DEG 18KT 4238 10530

$$

MAZUR

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 4, 8:43 PM MDT	Special Weather Statement	CYS	Albany	32 min
Jul 4, 8:52 PM MDT	Severe Thunderstorm Warning	CYS	Albany	20 min
Jul 4, 9:23 PM MDT	Special Weather Statement	CYS	Albany	37 min
Jul 5, 2:44 PM MDT	Special Weather Statement	CYS	Albany	31 min
Jul 5, 2:50 PM MDT	Special Weather Statement	CYS		25 min
Jul 5, 3:01 PM MDT	Special Weather Statement	CYS	Converse	29 min
Jul 5, 3:02 PM MDT	Special Weather Statement	CYS	Converse	28 min
Jul 5, 3:11 PM MDT	Severe Thunderstorm Warning	CYS	Converse	39 min
Jul 5, 3:21 PM MDT	Special Weather Statement	CYS		24 min
Jul 5, 3:48 PM MDT	Special Weather Statement	CYS	Platte	42 min
Jul 5, 3:55 PM MDT	Severe Thunderstorm Warning	CYS	Albany, Converse	50 min
Jul 5, 4:01 PM MDT	Special Weather Statement	CYS	Converse	44 min
Jul 5, 4:39 PM MDT	Severe Thunderstorm Warning	CYS	Albany, Platte	51 min
Jul 5, 5:02 PM MDT	Flash Flood Warning	CYS	Albany	5 hr
Jul 5, 5:26 PM MDT	Special Weather Statement	CYS	Platte	49 min
Jul 5, 5:44 PM MDT	Severe Thunderstorm Warning	CYS	Converse, Niobrara, Platte	46 min

Nearby

Severe Thunderstorm Warnings in Wyoming, 2012 Every severe thunderstorm warning in 2012

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.