A fast-moving system moved across Wyoming and brought locally heavy snow and high wind. Locally heavy snow fell in the Tetons and Wyoming Ranges, with 14 and 12 inches of new snow respectively.
Every event with a place to put it; 6 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS RIW wrote it up.
A fast-moving system moved across Wyoming and brought locally heavy snow and high wind. Locally heavy snow fell in the Tetons and Wyoming Ranges, with 14 and 12 inches of new snow respectively. Over South Pass, snow combined with wind gusting to almost 100 mph to bring white out conditions and closure of Highway 28 over the Wind River Mountains. High wind occurred in the vicinity of Casper and Lander as well, with wind gusts over 70 in both locations.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Riverton, WY wrote its last area forecast discussion before the first event at Mar 14, 10:23 AM MST, 1 hour 37 minutes earlier.
Area Forecast Discussion National Weather Service Riverton WY 1123 AM MDT Tue Mar 14 2023 .DISCUSSION...(Today through Monday) Issued at 221 AM MDT Tue Mar 14 2023 We are currently in a lull in the precipitation across the area. This will change though over the next several hours. With the contrast in weather, we will split the discussion into West and East of the Divide. West of the Divide...The first batch of precipitation associated with the Pacific system is now moving through Idaho and will arrive this morning across the west. The reasoning remains fairly similar this morning to previous shifts. Snowfall rates should be largely light to moderate during the day. And in the valleys, it should be warm enough for a rain / snow mix at times with highs climbing well into the 30s, keeping accumulations down. The heaviest snow looks to fall tonight as temperatures fall below freezing and some jet energy arrives to help enhance lift. Snowfall rates may approach 2 inches an hour a times across the mountains during this time, with heavy snow continuing into the morning hours. By the afternoon, the best forcing will have shifted east of the area with snowfall rates decreasing. In the valleys, mixing again will be likely be mid day with 700 millibar temperatures rising to minus 3 to minus 4 which would put snow levels around 6500 to 7000 feet. And there is another wrinkle this morning. This is again, like the last system, across Sweetwater County. The deeper moisture will spreading into the area on Wednesday morning and coinciding with the passage of an 120 knot jet across the area. This could lead to a period of heavy snow and possibly some snow squalls as well, The difference being is that temperatures will be warmer and it could fall as rain. I am concerned that the evaporational cooling may be enough to turn rain to snow for some heavy, wet snow Wednesday morning. The models are not in unison though so no highlights yet. The day shift should take a closer look at this though as it would impact Interstate 80 which can turn ugly very quickly. A period of quiet weather will then move in for Thursday and last into the weekend as ridging builds across the area. Other than a few mountain snow showers, especially on Sunday with a weak shortwave passage, otherwise dry conditions are expected. Temperatures will be below normal early on, but gradual moderation will continue into the weekend and the first day of Spring on Monday, at 3:28 pm to be exact. East of the Divide...Dry weather is expected through much of Wednesday as downsloping flow should keep any precipitation to the west. The main concern will be wind in the short term. The wind prone areas around Casper are already seeing wind gusts close to 50 mph. So, we have upgraded the high wind watch to a warning. The strongest wind still looks to be tonight into early tomorrow with the best downward forcing and strongest wind level winds, generally averaging 50 to 60 knots but possibly as strong as 70 knots on some models. These winds should subside as the southwest flow turns more west to northwesterly Wednesday afternoon and the pressure gradient relaxes following the frontal passage. Another area we are concerned about is the Lander Foothills. The 700 millibar winds are not as strong here though and do not last long. We will issue a Special Weather Statement for now to cover this. One good thing about the wind is it will mix out the inversions both today and tomorrow and bring warmer temperatures that will melt out some of the snowcover. Very warm temperatures are not expected though so rapid snow melt is not likely so any flooding concern looks minimal though Wednesday. The next question is for snow, or rain changing to snow. Precipitation will spread into the north in the afternoon, spreading southward at night and continuing into Wednesday. THe latest model runs have backed off on amounts though, with most remaining sub advisory for the most part. The highest amounts still look to be in places like the Wind River Basin and Casper with a brief period of upslope occurring. THe X factor is that there could be some banded snow which is hard to pinpoint and may bring locally higher amounts. No highlights need now though. Gusty wind will develop behind the front as well with the strongest wind in the usual favored northwest flow locations, especially Johnson County. Gusty wind will continue Thursday as well, and it will definitely feel like winter again. Like West of the Divide, quieter weather should return from Friday into the weekend with ridging building over the area. North flow will keep well below normal temperatures over the area on Friday, but some moderation will occur through the weekend as the strong March sun modifies the air mass. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) Issued at 1123 AM MDT Tue Mar 14 2023 West of the Divide...KBPI/KJAC/KPNA/KRKS Terminals It will be an active 24 hours as a winter storm moves through the area. Light snow has ended at KJAC for this afternoon, but some light snow showers will remain in the area. Light snow then moves back in around 01Z this evening at KJAC with prevailing MVFR/IFR through the rest of the TAF period. An intense band of heavy snow is possible from about 09Z to 12Z Wednesday morning at KJAC, which may result in a drop to LIFR during that time period. This band of snow is likely to impact KPNA, KBPI, and KRKS as well as it moves east across Wyoming. Snow begins at KPNA by 01Z this evening with prevailing IFR conditions expected through Tuesday night. At KBPI snow will move through periodically starting at about 02Z this evening. It will be breezy to windy at KRKS and KJAC through the TAF period, with gusts of 20 to 30 knots likely. Gusty winds are also likely as the band of heavy snow passes over the each terminal. Once the snow band moves through, snow will end at KBPI, KPNA, and KRKS, Wednesday morning. Mountains will be obscured over the next 24 hours. East of the Divide...KCOD/KCPR/KLND/KRIW/KWRL Terminals VFR conditions will prevail for most terminals through the TAF period, but KRIW and KCOD may drop to MVFR late Tuesday night into early Wednesday morning. Light snow is possible at KCOD from 08Z to 11Z as a band of snow moves through the area. This band of snow may be more of a rain/snow mix at KRIW as it moves through from 11Z to 13Z. It is possible KLND could see a rain snow mix as well early Wednesday morning, but for now chances remain lower there, so went with VCSH. The wind will be strong ahead of a cold front that is expected to pass through sometime Wednesday afternoon. KCPR will see the strongest winds, with gusts above 50 knots from the southwest possible tonight into tomorrow morning. There is potential for strong southwesterly wind at KLND and KRIW as well, mainly Wednesday morning right before the cold front pushes through. Please see the Aviation Weather Center and/or CWSU ZDV and ZLC for the latest information on icing and turbulence forecasts. && .FIRE WEATHER... Issued at 221 AM MDT Tue Mar 14 2023 A weather system will move into western Wyoming today and bring snow to the western mountains. Gusty wind will develop East of the Divide with high wind likely in the Green Mountains and Natrona County. Rain and snow showers will spread East of the Divide on Wednesday. Relative humidity will remain above critical levels. Mixing and smoke dispersal will be generally poor but fair to good in the northwestern mountains. && .RIW WATCHES/WARNINGS/ADVISORIES... Winter Storm Warning until midnight MDT Wednesday night for WYZ001-012-024. Winter Weather Advisory from 6 PM this evening to midnight MDT Wednesday night for WYZ002-013-023-025-027. Winter Storm Warning from 6 PM this evening to noon MDT Thursday for WYZ014-015. High Wind Warning until 3 PM MDT Wednesday for WYZ019-020. && DISCUSSION...Hattings AVIATION...Rowe FIRE WEATHER...Hattings
Hazardous Weather Outlook National Weather Service Riverton WY 333 AM MDT Tue Mar 14 2023 WYZ001>020-022>030-151400- Yellowstone National Park-Absaroka Mountains-Cody Foothills- North Big Horn Basin-Southwest Big Horn Basin- Southeast Big Horn Basin-Owl Creek and Bridger Mountains- Bighorn Mountains West-Bighorn Mountains Southeast- Northeast Johnson County-Southeast Johnson County- Teton and Gros Ventre Mountains-Jackson Hole- Wind River Mountains West-Wind River Mountains East- Upper Wind River Basin-Wind River Basin-Lander Foothills- Green Mountains and Rattlesnake Range- Natrona County Lower Elevations-Casper Mountain-Star Valley- Salt River and Wyoming Ranges-Upper Green River Basin Foothills- Upper Green River Basin-South Lincoln County- Rock Springs and Green River-Flaming Gorge-East Sweetwater County- 333 AM MDT Tue Mar 14 2023 ...Winter Storm Warnings and Winter Weather Advisories are in Effect to Wednesday Night and Thursday Morning... ...A High Wind Warning is Posted for Portions of Central Wyoming Tuesday Afternoon through Wednesday Afternoon... This Hazardous Weather Outlook is for Western and Central Wyoming. .DAY ONE...This Afternoon and Tonight. Snow returning to the western mountains today and continuing through tonight, with the heaviest snow expected tonight, especially after midnight. Please see Winter Weather Products for details. High wind likely from the Green Mountains into Natrona County this afternoon into tonight. Please see High Wind Warning for details. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Wednesday...Snow continuing in the west, tapering off in the afternoon. High wind continuing in the same locations, lessening later in the day. Wednesday Night to Thursday...Accumulating snow and gusty north wind possible across the lower elevations of northern, central, and southern Wyoming. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions.
The national radar mosaic for the moment the first event began.
3 winter storm, 3 high wind. Local standard time, as filed.
At the top of the Jackson Hole Ski Resort, 14 inches of new snow fell.
At the Blind Bull SNOTEL site, 12 inches of new snow fell.
High wind occurred mainly along the south side of Casper, with a maximum wind gust of 73 mph along Wyoming Boulevard. The Natrona County airport had a maximum wind gust of 59 mph.
Periods of snow combined with a period of hurricane force wind gusts to bring the closure of Highway 28 over South Pass. The maximum wind gust reported was 98 mph at Red Canyon.
High wind occurred in the Lander Foothills. A maximum wind gust of 72 mph occurred in Sinks Canyon State Park. The Lander airport had a maximum wind gust of 59 mph.
Wind gusts of 60 mph occurred along Highway 220 near the Pathfinder Reservoir.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wyoming in 2023Every state in 2023This day in weather historyWarnings in Wyoming, March 2023
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 1089142, 1089143, 1089147, 1089144, 1089145, 1089146.