Alert archive / Wyoming / Special Weather Statements in 2011

Special Weather Statement, NWS Riverton, WY

August 7, 2011Teton County, Wyoming

NWS Riverton, WY issued this special weather statement at Aug 7, 2011, 4:21 PM MDT for Teton County, Wyoming. It was in force for 39 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
Aug 7, 2011, 4:21 PM MDT (22:21 UTC)
Expired
Aug 7, 2011, 5:00 PM MDT
In force
39 min
Issued by
NWS Riverton, WY

County Teton County, WY

The radar

The Pocatello radar (KSFX), 213 km from the middle of the area, began a volume at 22:21 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, 10.4 hours before the alert went out and 252 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, Riverton, WY at 12:00Z on 2011-08-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Riverton, WY at 12:00Z on 2011-08-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 74 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3301 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
74 m²/s²
0-3 km storm-relative helicity
118 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.

710 
WWUS85 KRIW 072221
SPSRIW

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE RIVERTON WY
421 PM MDT SUN AUG 7 2011

WYZ001-072300-
YELLOWSTONE NATIONAL PARK WY-
421 PM MDT SUN AUG 7 2011

...SIGNIFICANT WEATHER ADVISORY FOR WESTERN PARK AND NORTHWESTERN
TETON COUNTIES IN NORTHWEST WYOMING UNTIL 500 PM MDT...

AT 415 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM NEAR MYSTIC FALLS...OR 18 MILES SOUTHEAST OF WEST
YELLOWSTONE...MOVING EAST AT 30 MPH.

WIND GUSTS UP TO 40 TO 50 MPH ARE EXPECTED WITH THIS STORM...ALONG 
WITH FREQUENT DANGEROUS LIGHTNING.

THIS STORM WILL BE NEAR...
OLD FAITHFUL...KEPLER CASCADES...SCAUP LAKE...LOWER BASIN LAKE AND 
FOUNTAIN PAINT POT AROUND 425 PM MDT.
CRAIG PASS AROUND 435 PM MDT.
GRAND LOOP RD GRANT TO LAKE AND LAKE AROUND 500 PM MDT.

IF THREATENING WEATHER APPROACHES YOUR AREA...TAKE SHELTER IN A
STURDY BUILDING.

REPORT HAZARDOUS WEATHER TO THE NATIONAL WEATHER SERVICE OFFICE IN
RIVERTON AT 1-800-211-1448.

LAT...LON 4447 11104 4453 11105 4453 11104 4465 11029
      4441 11024 4435 11105 4446 11105
TIME...MOT...LOC 2220Z 261DEG 24KT 4447 11085

$$

LIPSON

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 7, 1:58 PM MDTSpecial Weather StatementRIWHot Springs47 min
Aug 7, 2:49 PM MDTSpecial Weather StatementRIWWashakie41 min
Aug 7, 2:58 PM MDTSpecial Weather StatementRIWHot Springs47 min
Aug 7, 3:17 PM MDTSpecial Weather StatementRIWPark43 min
Aug 7, 3:18 PM MDTSpecial Weather StatementRIW42 min
Aug 7, 3:32 PM MDTSpecial Weather StatementRIWWashakie43 min
Aug 7, 3:50 PM MDTSpecial Weather StatementRIW40 min
Aug 7, 3:55 PM MDTSpecial Weather StatementRIW50 min
Aug 7, 3:56 PM MDTSpecial Weather StatementRIWFremont49 min
Aug 7, 3:57 PM MDTSpecial Weather StatementRIWPark48 min
Aug 7, 4:16 PM MDTSpecial Weather StatementRIWWashakie44 min
Aug 7, 5:05 PM MDTSpecial Weather StatementRIWFremont25 min
Aug 7, 5:26 PM MDTSpecial Weather StatementRIWHot Springs49 min

Nearby

Special Weather Statements in Wyoming, 2011Every special weather statement 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.