Alert archive / Wyoming / Winter Storm Warnings in 2021

Winter Storm Warning 6, NWS Riverton, WY

March 9, 2021Johnson County, Natrona County, Wyoming

NWS Riverton, WY issued this winter storm warning at Mar 9, 2021, 3:09 AM MST for Johnson County, Natrona County, Wyoming. It took effect at Mar 9, 2021, 8:00 PM MST. It was in force for 21 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Mar 9, 2021, 3:09 AM MST (10:09 UTC)
In effect from
Mar 9, 2021, 8:00 PM MST
Expired
Mar 10, 2021, 5:00 PM MST
In force
21 hr
Issued by
NWS Riverton, WY

Counties Johnson County, WY, Natrona County, WY

The radar

The Riverton/Lander radar (KRIW), 152 km from the middle of the area, began a volume at 10:14 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 00:00Z, 10.2 hours before the alert went out and 146 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 2021-03-09Temperature 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 00:00Z on 2021-03-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 25 square meters per square second.1939587897Sfc1 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
3175 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
25 m²/s²
0-3 km storm-relative helicity
100 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

655 
WWUS45 KRIW 091009
WSWRIW

URGENT - WINTER WEATHER MESSAGE
National Weather Service Riverton WY
309 AM MST Tue Mar 9 2021

...Significant Snowfall Expected Tonight and Wednesday...

.A weather system will move northeast across Wyoming late this
afternoon through Wednesday. Colder temperatures and widespread 
snow are expected in areas along and east of the Continental 
Divide.

WYZ011-020-100000-
/O.UPG.KRIW.WS.A.0003.210310T0300Z-210311T0000Z/
/O.NEW.KRIW.WS.W.0006.210310T0300Z-210311T0000Z/
Southeast Johnson County-Natrona County Lower Elevations-
Including the cities of Kaycee and Casper
309 AM MST Tue Mar 9 2021

...WINTER STORM WARNING IN EFFECT FROM 8 PM THIS EVENING TO 5 PM
MST WEDNESDAY...

* WHAT...Heavy snow expected. Total snow accumulations of 6 to 9 
  inches.

* WHERE...Southeast Johnson County and Natrona County Lower 
  Elevations.

* WHEN...From 8 PM this evening to 5 PM MST Wednesday.

* IMPACTS...Plan on slippery or snow covered road conditions. 
  The hazardous conditions would impact the Wednesday morning 
  commute.

* ADDITIONAL DETAILS...Interstate 25 and other major highways 
  will be impacted by this storm. Allow extra time to reach your 
  destination..

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ019-022-100000-
/O.UPG.KRIW.WS.A.0003.210310T0300Z-210311T0000Z/
/O.NEW.KRIW.WW.Y.0018.210310T0300Z-210311T0000Z/
Green Mountains and Rattlesnake Range-Casper Mountain-
Including the city of Jeffrey City
309 AM MST Tue Mar 9 2021

...WINTER WEATHER ADVISORY IN EFFECT FROM 8 PM THIS EVENING TO
5 PM MST WEDNESDAY...

* WHAT...Snow expected. Total snow accumulations of 3 to 7 inches,
  with localized ares up to 9 inches in the eastern Green 
  Mountains. Casper Mountain will see 7 to 11 inches.

* WHERE...Green Mountains and Rattlesnake Range and Casper 
  Mountain.

* WHEN...From 8 PM this evening to 5 PM MST Wednesday.

* IMPACTS...Plan on slippery or snow covered road conditions. 
  The hazardous conditions would impact the Wednesday morning 
  commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ015-100000-
/O.UPG.KRIW.WS.A.0003.210310T0300Z-210311T0000Z/
/O.NEW.KRIW.WW.Y.0018.210310T0300Z-210311T0000Z/
Wind River Mountains East-
309 AM MST Tue Mar 9 2021

...WINTER WEATHER ADVISORY IN EFFECT FROM 8 PM THIS EVENING TO
5 PM MST WEDNESDAY...

* WHAT...Snow expected. Total snow accumulations of 6 to 10 
  inches.

* WHERE...Wind River Mountains East.

* WHEN...From 8 PM this evening to 5 PM MST Wednesday.

* IMPACTS...Plan on slippery or snow covered road conditions. 
  The hazardous conditions would impact the Wednesday morning 
  commute.

* ADDITIONAL DETAILS...The Red Canyon area up to South Pass will 
  be impacted by this storm. Allow extra time to reach your 
  destination.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ018-100000-
/O.UPG.KRIW.WS.A.0003.210310T0300Z-210311T0000Z/
/O.NEW.KRIW.WW.Y.0018.210310T0300Z-210311T0000Z/
Lander Foothills-
Including the city of Lander
309 AM MST Tue Mar 9 2021

...WINTER WEATHER ADVISORY IN EFFECT FROM 8 PM THIS EVENING TO
5 PM MST WEDNESDAY...

* WHAT...Snow expected. Total snow accumulations of 4 to 6 
  inches.

* WHERE...Lander Foothills.

* WHEN...From 8 PM this evening to 5 PM MST Wednesday.

* IMPACTS...Plan on slippery or snow covered road conditions. 
  The hazardous conditions would impact the Wednesday morning 
  commute.

* ADDITIONAL DETAILS...The Red Canyon area up to South Pass will 
  be impacted by this storm. Allow extra time to reach your 
  destination.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ007>009-100000-
/O.UPG.KRIW.WS.A.0003.210310T0300Z-210311T0000Z/
/O.NEW.KRIW.WW.Y.0018.210310T0300Z-210311T0000Z/
Owl Creek and Bridger Mountains-Bighorn Mountains West-
Bighorn Mountains Southeast-
309 AM MST Tue Mar 9 2021

...WINTER WEATHER ADVISORY IN EFFECT FROM 8 PM THIS EVENING TO
5 PM MST WEDNESDAY...

* WHAT...Snow expected. Total snow accumulations of 2 to 10 
  inches.

* WHERE...Owl Creek and Bridger Mountains, Bighorn Mountains 
  West and Bighorn Mountains Southeast.

* WHEN...From 8 PM this evening to 5 PM MST Wednesday.

* IMPACTS...Travel could be very difficult at time over Granite
  and Powder River passes. The hazardous conditions would impact
  travelers in the Bighorn Range.

* ADDITIONAL DETAILS...Allow extra time to reach your 
  destination.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ010-100000-
/O.UPG.KRIW.WS.A.0003.210310T0300Z-210311T0000Z/
/O.NEW.KRIW.WW.Y.0018.210310T0300Z-210311T0000Z/
Northeast Johnson County-
Including the city of Buffalo
309 AM MST Tue Mar 9 2021

...WINTER WEATHER ADVISORY IN EFFECT FROM 8 PM THIS EVENING TO
5 PM MST WEDNESDAY...

* WHAT...Snow expected. Total snow accumulations of 2 to 3 
  inches.

* WHERE...Northeast Johnson County.

* WHEN...From 8 PM this evening to 5 PM MST Wednesday.

* IMPACTS...Plan on slippery or snow covered road conditions. 
  The hazardous conditions would impact the Wednesday morning 
  commute.

* ADDITIONAL DETAILS...Interstates 25 and 90, as well as other 
  major highways, will be impacted by this storm. Allow extra 
  time to reach your destination.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ016-017-100000-
/O.NEW.KRIW.WW.Y.0018.210310T0300Z-210311T0000Z/
Upper Wind River Basin-Wind River Basin-
Including the cities of Dubois, Riverton, and Shoshoni
309 AM MST Tue Mar 9 2021

...WINTER WEATHER ADVISORY IN EFFECT FROM 8 PM THIS EVENING TO
5 PM MST WEDNESDAY...

* WHAT...Snow expected. Total snow accumulations of 3 to 5 
  inches.

* WHERE...Wind River Basin.

* WHEN...From 8 PM this evening to 5 PM MST Wednesday.

* IMPACTS...Plan on slippery or snow covered road conditions. 
  The hazardous conditions would impact the Wednesday morning 
  commute.

* ADDITIONAL DETAILS...Allow extra time to reach your 
  destination.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

For more information from the National Weather Service visit
http://weather.gov/riw
4 follow-up statements
835 
WWUS45 KRIW 092128
WSWRIW

URGENT - WINTER WEATHER MESSAGE
National Weather Service Riverton WY
228 PM MST Tue Mar 9 2021

...Significant Snowfall Expected Tonight and Wednesday...

.A weather system is still on-track to produce widespread
accumulating snow late this evening through at least midday
Wednesday along and east of the Continental Divide.

WYZ011-020-101400-
/O.CON.KRIW.WS.W.0006.210310T0300Z-210311T0000Z/
Southeast Johnson County-Natrona County Lower Elevations-
Including the cities of Kaycee and Casper
228 PM MST Tue Mar 9 2021

...WINTER STORM WARNING REMAINS IN EFFECT FROM 8 PM THIS EVENING
TO 5 PM MST WEDNESDAY...

* WHAT...Snow with total accumulations of 6 to 9 inches.

* WHERE...Lower elevations of Natrona County and far southern
  Johnson County.

* WHEN...8 PM Tuesday to 5 PM MST Wednesday. The heaviest snow
  will fall between 11 PM Tuesday and 9 AM Wednesday.

* IMPACTS...Plan on slippery or snow covered road conditions. The
  hazardous conditions will impact the Wednesday morning commute.

* ADDITIONAL DETAILS...Interstate 25 and other major highways will
  be impacted by this storm. Allow extra time to reach your
  destination. Conditions should improve around midday Wednesday 
  as snowfall rates slow down.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency.

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ019-022-101400-
/O.CON.KRIW.WW.Y.0018.210310T0300Z-210311T0000Z/
Green Mountains and Rattlesnake Range-Casper Mountain-
Including the city of Jeffrey City
228 PM MST Tue Mar 9 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 8 PM THIS
EVENING TO 5 PM MST WEDNESDAY...

* WHAT...Snow with total accumulations of 4 to 8 inches. Casper 
  Mountain could see totals around one foot.

* WHERE...Casper Mountain, and the Green Mountains and Rattlesnake
  Range.

* WHEN...8 PM Tuesday to 5 PM MST Wednesday.

* IMPACTS...Plan on slippery or snow covered road conditions. 
  The hazardous conditions would impact the Wednesday morning 
  commute.

* ADDITIONAL DETAILS...US 287 and Wyoming Highway 220 will be 
  impacted by this storm. Allow extra time to reach your 
  destination. Conditions should improve around midday Wednesday 
  as snowfall rates slow down.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ015-101400-
/O.CON.KRIW.WW.Y.0018.210310T0300Z-210311T0000Z/
Wind River Mountains East-
228 PM MST Tue Mar 9 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 8 PM THIS
EVENING TO 5 PM MST WEDNESDAY...

* WHAT...Snow with total accumulations of 6 to 10 inches.

* WHERE...Wind River Mountains East.

* WHEN...8 PM Tuesday to 5 PM MST Wednesday.

* IMPACTS...Plan on slick and snow covered road conditions over
  South Pass. The hazardous conditions will impact the Wednesday 
  morning commute.

* ADDITIONAL DETAILS...Wyoming Highway 28 from Red Canyon over 
  South Pass will be impacted by this storm. Allow extra time to 
  reach your destination. Conditions should improve around midday 
  Wednesday as snowfall rates slow down.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ016>018-101400-
/O.CON.KRIW.WW.Y.0018.210310T0300Z-210311T0000Z/
Upper Wind River Basin-Wind River Basin-Lander Foothills-
Including the cities of Dubois, Riverton, Shoshoni, and Lander
228 PM MST Tue Mar 9 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 8 PM THIS
EVENING TO 5 PM MST WEDNESDAY...

* WHAT...Snow with total accumulations of 3 to 5 inches. Locally
  higher totals up to 8 inches in the foothills of the Wind River
  Range.

* WHERE...Wind River Basin.

* WHEN...8 PM Tuesday to 5 PM MST Wednesday.

* IMPACTS...Plan on slippery or snow covered road conditions. 
  The hazardous conditions would impact the Wednesday morning 
  commute.

* ADDITIONAL DETAILS...Allow extra time to reach your destination.
  Travel conditions should improve around midday Wednesday as
  snowfall rates slow down and temperatures warm slightly.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ007>009-101400-
/O.CON.KRIW.WW.Y.0018.210310T0300Z-210311T0000Z/
Owl Creek and Bridger Mountains-Bighorn Mountains West-
Bighorn Mountains Southeast-
228 PM MST Tue Mar 9 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 8 PM THIS
EVENING TO 5 PM MST WEDNESDAY...

* WHAT...Snow with total accumulations of 5 to 10 inches. The
  heaviest amounts will fall on the east facing slopes of the 
  Bighorn Range.

* WHERE...Owl Creek and Bridger Mountains, Bighorn Mountains 
  West, and Bighorn Mountains Southeast.

* WHEN...8 PM Tuesday to 5 PM MST Wednesday.

* IMPACTS...Travel could be very difficult at times over Granite
  and Powder River passes impacting travelers crossing the Bighorn
  Range. Road conditions will be slick through Wind River Canyon
  on the Wednesday morning commute.

* ADDITIONAL DETAILS...Allow extra time to reach your 
  destination.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ010-101400-
/O.CON.KRIW.WW.Y.0018.210310T0300Z-210311T0000Z/
Northeast Johnson County-
Including the city of Buffalo
228 PM MST Tue Mar 9 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 8 PM THIS
EVENING TO 5 PM MST WEDNESDAY...

* WHAT...Snow with total accumulations of 2 to 4 inches.

* WHERE...Northeast Johnson County.

* WHEN...8 PM Tuesday to 5 PM MST Wednesday. The best chance for
  snow will come after midnight Wednesday.

* IMPACTS...Plan on slippery or snow covered road conditions. The
  hazardous conditions will impact the Wednesday morning commute.

* ADDITIONAL DETAILS...Interstates 25 and 90, as well as other 
  major highways, will be impacted by this storm. Allow extra 
  time to reach your destination.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

For more information from the National Weather Service visit
http://weather.gov/riw
859 
WWUS45 KRIW 100317
WSWRIW

URGENT - WINTER WEATHER MESSAGE
National Weather Service Riverton WY
817 PM MST Tue Mar 9 2021

...Significant Snowfall Tonight and Wednesday...

.A weather system will bring significant snowfall to central
Wyoming tonight and Wednesday. The heaviest snow will occur
between midnight and 9 AM. 

WYZ011-020-101300-
/O.CON.KRIW.WS.W.0006.000000T0000Z-210311T0000Z/
Southeast Johnson County-Natrona County Lower Elevations-
Including the cities of Kaycee and Casper
817 PM MST Tue Mar 9 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 PM MST
WEDNESDAY...

* WHAT...Snow with total accumulations of 6 to 9 inches.

* WHERE...Lower elevations of Natrona County and far southern 
  Johnson County.

* WHEN...Now until 5 PM Wednesday. The heaviest snow will fall 
  between midnight and 9 AM Wednesday.

* IMPACTS...Plan on slippery or snow covered road conditions
  including Interstate 25. The hazardous conditions will impact 
  the Wednesday morning commute. 

* ADDITIONAL DETAILS...The snow will be heavy and wet. Please do 
  not overexert yourself when shoveling as it could lead to 
  serious health conditions. Allow extra time to reach your 
  destination. Conditions should improve around midday Wednesday 
  as snowfall rates slow down. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency.

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ019-022-101300-
/O.CON.KRIW.WW.Y.0018.000000T0000Z-210311T0000Z/
Green Mountains and Rattlesnake Range-Casper Mountain-
Including the city of Jeffrey City
817 PM MST Tue Mar 9 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 PM MST
WEDNESDAY...

* WHAT...Snow with total accumulations of 4 to 8 inches. Casper 
  Mountain could see totals around one foot.

* WHERE...Casper Mountain, and the Green Mountains and 
  Rattlesnake Range.

* WHEN...Now until 5 PM Wednesday. The heaviest snow will occur 
  from midnight through 9 AM.

* IMPACTS...Plan on slippery or snow covered road conditions
  including US 287 and Wyoming 220. The hazardous conditions 
  would impact the Wednesday morning commute.

* ADDITIONAL DETAILS...The snow will be heavy and wet. Please do 
  not overexert yourself when shoveling as it could lead to 
  serious health conditions. Allow extra time to reach your 
  destination. Conditions should improve around midday Wednesday 
  as snowfall rates slow down.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ015-101300-
/O.CON.KRIW.WW.Y.0018.000000T0000Z-210311T0000Z/
Wind River Mountains East-
817 PM MST Tue Mar 9 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 PM MST
WEDNESDAY...

* WHAT...Snow with total accumulations of 6 to 10 inches.

* WHERE...Wind River Mountains East.

* WHEN...Now until 5 PM Wednesday. The heaviest snow is expected
  between midnight and 9 AM.

* IMPACTS...Plan on slick and snow covered road conditions over 
  South Pass. The hazardous conditions will impact the Wednesday 
  morning commute.

* ADDITIONAL DETAILS...Wyoming Highway 28 from Red Canyon over 
  South Pass will be impacted by this storm. Allow extra time to 
  reach your destination. Conditions should improve around 
  midday Wednesday as snowfall rates slow down.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ016>018-101300-
/O.CON.KRIW.WW.Y.0018.000000T0000Z-210311T0000Z/
Upper Wind River Basin-Wind River Basin-Lander Foothills-
Including the cities of Dubois, Riverton, Shoshoni, and Lander
817 PM MST Tue Mar 9 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 PM MST
WEDNESDAY...

* WHAT...Snow with total accumulations of 3 to 5 inches. Locally 
  higher totals up to 8 inches in the foothills of the Wind 
  River Range.

* WHERE...Wind River Basin. 

* WHEN...Now until 5 PM Wednesday. The heaviest snowfall will
  occur between Midnight and 9 AM.

* IMPACTS...Plan on slippery or snow covered road conditions. 
  The hazardous conditions would impact the Wednesday morning 
  commute.

* ADDITIONAL DETAILS...The snow will be heavy and wet. Please do 
  not overexert yourself when shoveling as it could lead to 
  serious health conditions. Allow extra time to reach your 
  destination. Travel conditions should improve around midday 
  Wednesday as snowfall rates slow down and temperatures warm 
  slightly.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ007>009-101300-
/O.CON.KRIW.WW.Y.0018.000000T0000Z-210311T0000Z/
Owl Creek and Bridger Mountains-Bighorn Mountains West-
Bighorn Mountains Southeast-
817 PM MST Tue Mar 9 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 PM MST
WEDNESDAY...

* WHAT...Snow with total accumulations of 5 to 10 inches. The 
  heaviest amounts will fall on the east facing slopes of the 
  Bighorn Range.

* WHERE...Owl Creek and Bridger Mountains, Bighorn Mountains 
  West, and Bighorn Mountains Southeast.

* WHEN...Now until 5 PM Wednesday.

* IMPACTS...Travel could be very difficult at times over Granite 
  and Powder River passes impacting travelers crossing the 
  Bighorn Range. Road conditions will be slick through Wind 
  River Canyon on the Wednesday morning commute.

* ADDITIONAL DETAILS...Allow extra time to reach your 
  destination.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ010-101300-
/O.CON.KRIW.WW.Y.0018.000000T0000Z-210311T0000Z/
Northeast Johnson County-
Including the city of Buffalo
817 PM MST Tue Mar 9 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 PM MST
WEDNESDAY...

* WHAT...Snow with total accumulations of 2 to 4 inches.

* WHERE...Northeast Johnson County.

* WHEN...Now until 5 PM Wednesday. The heaviest snow is expected
  to occur between midnight and 9 AM. 

* IMPACTS...Plan on slippery or snow covered road conditions
  including Interstates 25 and 90. The hazardous conditions will 
  impact the Wednesday morning commute.

* ADDITIONAL DETAILS...The snow will be heavy and wet. Please do 
  not overexert yourself when shoveling as it could lead to 
  serious health conditions. Allow extra time to reach your 
  destination.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

Team Riverton/21
560 
WWUS45 KRIW 101011
WSWRIW

URGENT - WINTER WEATHER MESSAGE
National Weather Service Riverton WY
311 AM MST Wed Mar 10 2021

...Significant Snowfall Through this Afternoon...

.A weather system will continue to produce significant snowfall 
over central Wyoming through this afternoon. 

WYZ011-020-110000-
/O.CON.KRIW.WS.W.0006.000000T0000Z-210311T0000Z/
Southeast Johnson County-Natrona County Lower Elevations-
Including the cities of Kaycee and Casper
311 AM MST Wed Mar 10 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...

* WHAT...Heavy snow. Additional snow accumulations of 4 to 6
  inches. Winds gusting 25 to 35 mph.

* WHERE...Lower elevations of Natrona County and far southern 
  Johnson County.

* WHEN...Now until 5 PM Wednesday. 

* IMPACTS...Plan on slippery or snow covered road conditions
  including Interstate 25. The hazardous conditions will impact
  the morning commute.

* ADDITIONAL DETAILS...The snow will be heavy and wet. Please do
  not overexert yourself when shoveling. Allow extra time to reach
  your destination. Conditions should improve around midday as 
  snowfall rates slow down.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency.

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ019-022-110000-
/O.CON.KRIW.WW.Y.0018.000000T0000Z-210311T0000Z/
Green Mountains and Rattlesnake Range-Casper Mountain-
Including the city of Jeffrey City
311 AM MST Wed Mar 10 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...

* WHAT...Snow. Additional snow accumulations of 2 to 4 inches. 
  Winds gusting as high as 35 mph.

* WHERE...Casper Mountain, and the Green Mountains and 
  Rattlesnake Range.

* WHEN...Now until 5 PM Wednesday. 

* IMPACTS...Plan on slippery or snow covered road conditions 
  including US 287 and Wyoming 220. The hazardous conditions 
  would impact the Wednesday morning commute.

* ADDITIONAL DETAILS...The snow will be heavy and wet. Please do
  not overexert yourself when shoveling. Allow extra time to reach
  your destination. Conditions should improve around midday as 
  snowfall rates slow down.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ015-110000-
/O.CON.KRIW.WW.Y.0018.000000T0000Z-210311T0000Z/
Wind River Mountains East-
311 AM MST Wed Mar 10 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...

* WHAT...Snow. Additional snow accumulations of 3 to 6 inches.

* WHERE...Wind River Mountains East.

* WHEN...Now until 5 PM Wednesday. 

* IMPACTS...Plan on slick and snow covered road conditions over 
  South Pass. The hazardous conditions will impact the Wednesday 
  morning commute.

* ADDITIONAL DETAILS...Wyoming Highway 28 from Red Canyon over
  South Pass will be impacted by this storm. Allow extra time to
  reach your destination. Conditions should improve around midday 
  as snowfall rates slow down.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ016>018-110000-
/O.CON.KRIW.WW.Y.0018.000000T0000Z-210311T0000Z/
Upper Wind River Basin-Wind River Basin-Lander Foothills-
Including the cities of Dubois, Riverton, Shoshoni, and Lander
311 AM MST Wed Mar 10 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...

* WHAT...Snow. Additional snow accumulations of 2 to 3 inches.

* WHERE...Wind River Basin.

* WHEN...Now until 5 PM Wednesday. 

* IMPACTS...Plan on slippery or snow covered road conditions. 
  The hazardous conditions would impact the Wednesday morning 
  commute.

* ADDITIONAL DETAILS...The snow will be heavy and wet. Please do
  not overexert yourself when shoveling. Allow extra time to reach
  your destination. Conditions should improve around midday as
  snowfall rates slow down and temperatures warm slightly.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ007>009-110000-
/O.CON.KRIW.WW.Y.0018.000000T0000Z-210311T0000Z/
Owl Creek and Bridger Mountains-Bighorn Mountains West-
Bighorn Mountains Southeast-
311 AM MST Wed Mar 10 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...

* WHAT...Snow. Additional snow accumulations of 3 to 6 inches.

* WHERE...Owl Creek and Bridger Mountains, Bighorn Mountains 
  West, and Bighorn Mountains Southeast.

* WHEN...Now until 5 PM Wednesday.

* IMPACTS...Travel could be very difficult at times over Granite
  and Powder River passes impacting travelers crossing the Bighorn
  Range. Road conditions will be slick through Wind River Canyon
  on the morning commute.

* ADDITIONAL DETAILS...Allow extra time to reach your 
  destination.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ010-110000-
/O.CON.KRIW.WW.Y.0018.000000T0000Z-210311T0000Z/
Northeast Johnson County-
Including the city of Buffalo
311 AM MST Wed Mar 10 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...

* WHAT...Snow. Additional snow accumulations of 1 to 3 inches.

* WHERE...Northeast Johnson County.

* WHEN...Now until 5 PM Wednesday. 

* IMPACTS...Plan on slippery or snow covered road conditions 
  including Interstates 25 and 90. The hazardous conditions will 
  impact the Wednesday morning commute.

* ADDITIONAL DETAILS...The snow will be heavy and wet. Please do
  not overexert yourself when shoveling. Allow extra time to 
  reach your destination.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

For more information from the National Weather Service visit
http://weather.gov/riw
033 
WWUS45 KRIW 102344
WSWRIW

URGENT - WINTER WEATHER MESSAGE
National Weather Service Riverton WY
444 PM MST Wed Mar 10 2021

WYZ011-020-110045-
/O.EXP.KRIW.WS.W.0006.000000T0000Z-210311T0000Z/
Southeast Johnson County-Natrona County Lower Elevations-
Including the cities of Kaycee and Casper
444 PM MST Wed Mar 10 2021

...WINTER STORM WARNING WILL EXPIRE AT 5 PM MST THIS AFTERNOON...

Snow has ended across the area. Although light snow may remain
possible this evening, any additional accumulation will be little
to none.

$$

WYZ019-022-110045-
/O.EXP.KRIW.WW.Y.0018.000000T0000Z-210311T0000Z/
Green Mountains and Rattlesnake Range-Casper Mountain-
Including the city of Jeffrey City
444 PM MST Wed Mar 10 2021

...WINTER WEATHER ADVISORY WILL EXPIRE AT 5 PM MST THIS
AFTERNOON...

Snow has ended across the area. Although light snow may remain
possible this evening, any additional accumulation will be little
to none.

$$

WYZ015-110045-
/O.EXP.KRIW.WW.Y.0018.000000T0000Z-210311T0000Z/
Wind River Mountains East-
444 PM MST Wed Mar 10 2021

...WINTER WEATHER ADVISORY WILL EXPIRE AT 5 PM MST THIS
AFTERNOON...

Snow has ended across the area. Although light snow may remain
possible this evening, any additional accumulation will be little
to none.

$$

WYZ016>018-110045-
/O.EXP.KRIW.WW.Y.0018.000000T0000Z-210311T0000Z/
Upper Wind River Basin-Wind River Basin-Lander Foothills-
Including the cities of Dubois, Riverton, Shoshoni, and Lander
444 PM MST Wed Mar 10 2021

...WINTER WEATHER ADVISORY WILL EXPIRE AT 5 PM MST THIS
AFTERNOON...

Snow has ended across the area. Although light snow may remain
possible this evening, any additional accumulation will be little
to none.

$$

WYZ007>009-110045-
/O.EXP.KRIW.WW.Y.0018.000000T0000Z-210311T0000Z/
Owl Creek and Bridger Mountains-Bighorn Mountains West-
Bighorn Mountains Southeast-
444 PM MST Wed Mar 10 2021

...WINTER WEATHER ADVISORY WILL EXPIRE AT 5 PM MST THIS
AFTERNOON...

Snow has ended across the area. Although light snow may remain
possible this evening, any additional accumulation will be little
to none.

$$

WYZ010-110045-
/O.EXP.KRIW.WW.Y.0018.000000T0000Z-210311T0000Z/
Northeast Johnson County-
Including the city of Buffalo
444 PM MST Wed Mar 10 2021

...WINTER WEATHER ADVISORY WILL EXPIRE AT 5 PM MST THIS
AFTERNOON...

Snow has ended across the area. Although light snow may remain
possible this evening, any additional accumulation will be little
to none.

$$

For more information from the National Weather Service visit
http://weather.gov/riw

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 9, 3:09 AM MSTWinter Weather AdvisoryRIWBig Horn, Fremont, Hot Springs, Johnson, Natrona, Sublette and 2 more38 hr

Nearby

Winter Storm Warnings in Wyoming, 2021Every winter storm warning in 2021

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.