Alert archive / Wyoming / Tornado Warnings in 2009

Tornado Warning 2, NWS Riverton, WY

June 13, 2009Natrona County, Wyoming

NWS Riverton, WY issued this tornado warning at Jun 13, 2009, 7:27 PM MDT for Natrona County, Wyoming. It was in force for 33 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
Jun 13, 2009, 7:27 PM MDT (01:27 UTC)
Expired
Jun 13, 2009, 8:00 PM MDT
In force
33 min
Issued by
NWS Riverton, WY
Area
Storm-based polygon

County Natrona County, WY

The radar

The Riverton/Lander radar (KRIW), 187 km from the middle of the area, began a volume at 01:29 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Jun 13, 1:56 PM MDTTornado WatchSPC9 hr

The nearest sounding before it

Riverton, WY (KRIW), launched 00:00Z, 1.5 hours before the alert went out and 181 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 00:00Z on 2009-06-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 210 joules per kilogram.LCLLFCEL10008507005003002001001 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 00:00Z on 2009-06-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 23 square meters per square second.193958Sfc1 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
210 J/kg
Mixed-layer CIN
-69 J/kg
Mixed-layer LCL
1959 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
23 m²/s²
0-3 km storm-relative helicity
28 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.

000 
WFUS55 KRIW 140127
TORRIW
WYC025-140200-
/O.NEW.KRIW.TO.W.0002.090614T0127Z-090614T0200Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE RIVERTON WY
727 PM MDT SAT JUN 13 2009

THE NATIONAL WEATHER SERVICE IN RIVERTON HAS ISSUED A

* TORNADO WARNING FOR...
  EAST CENTRAL NATRONA COUNTY IN CENTRAL WYOMING...

* UNTIL 800 PM MDT

* AT 726 PM MDT...WEATHER SERVICE DOPPLER RADAR CONTINUED TO INDICATE
  A SEVERE THUNDERSTORM WITH STRONG ROTATION 6 MILES NORTHEAST OF
  EVANSVILLE...OR 10 MILES NORTHEAST OF CASPER...MOVING EAST AT 15
  MPH.

* THE TORNADO WILL BE NEAR...
  RURAL EASTERN NATRONA COUNTY AT 740 PM

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS TORNADO WARNING REPLACES THE PREVIOUS WARNING THAT WAS IN EFFECT
FOR EAST CENTRAL NATRONA COUNTY.

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.

&&

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

LAT...LON 4318 10609 4289 10609 4286 10626 4301 10636
TIME...MOT...LOC 0127Z 249DEG 13KT 4294 10620

$$

C. BAKER
2 follow-up statements
000 
WWUS55 KRIW 140142
SVSRIW

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE RIVERTON WY
742 PM MDT SAT JUN 13 2009

WYC025-140200-
/O.CON.KRIW.TO.W.0002.000000T0000Z-090614T0200Z/
NATRONA WY-
742 PM MDT SAT JUN 13 2009

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 800 PM MDT FOR EAST
CENTRAL NATRONA COUNTY...

AT 741 PM MDT...WEATHER SERVICE DOPPLER RADAR CONTINUED TO INDICATE A
SEVERE THUNDERSTORM WITH STRONG ROTATION.  THIS TORNADO WAS LOCATED
OVER EXTREME EAST CENTRAL NATRONA COUNTY...OR 14 MILES NORTHEAST OF
CASPER...MOVING EAST AT 15 MPH.

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.

THIS IS A DANGEROUS STORM ACT QUICKLY. IF YOU ARE IN THE PATH OF
THIS TORNADO MOVE TO THE LOWEST FLOOR OF A STURDY BUILDING.

IN ADDITION TO THE TORNADO...THIS STORM IS CAPABLE OF PRODUCING 
QUARTER SIZE HAIL AND WINDS OF 60 MPH.

&&

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

LAT...LON 4294 10623 4305 10625 4313 10609 4291 10609
TIME...MOT...LOC 0142Z 249DEG 13KT 4298 10614

$$

C. BAKER
000 
WWUS55 KRIW 140156
SVSRIW

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE RIVERTON WY
756 PM MDT SAT JUN 13 2009

WYC025-140206-
/O.EXP.KRIW.TO.W.0002.000000T0000Z-090614T0200Z/
NATRONA WY-
756 PM MDT SAT JUN 13 2009

...THE TORNADO WARNING FOR EAST CENTRAL NATRONA COUNTY WILL EXPIRE AT
800 PM MDT...

THE STORM HAS DECREASED IN INTENSITY AND IS NO LONGER SEVERE.
THEREFORE...THE WARNING WILL BE ALLOWED TO EXPIRE.

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

LAT...LON 4294 10623 4305 10625 4313 10609 4291 10609
TIME...MOT...LOC 0156Z 249DEG 13KT 4300 10607

$$

C. BAKER

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 13, 6:04 PM MDTSevere Thunderstorm WarningRIWFremont41 min
Jun 13, 7:07 PM MDTSevere Thunderstorm WarningRIWNatrona38 min
Jun 13, 7:18 PM MDTSevere Thunderstorm WarningRIWFremont42 min
Jun 13, 8:33 PM MDTSevere Thunderstorm WarningRIWNatrona42 min
Jun 13, 9:11 PM MDTFlash Flood WarningRIWNatrona2 hr
Jun 14, 2:15 PM MDTSevere Thunderstorm WarningRIWHot Springs45 min
Jun 14, 2:54 PM MDTSevere Thunderstorm WarningRIWHot Springs66 min
Jun 14, 2:57 PM MDTTornado WarningRIWHot Springs47 min

Nearby

Tornado Warnings in Wyoming, 2009Every tornado warning in 2009Tornadoes in 2009

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.