A cold front moved across Wyoming and brought locally heavy snow to the Tetons. At the Jackson Hole Ski Resort, 15 inches of new snow was measured.
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The episode as NWS RIW wrote it up.
A cold front moved across Wyoming and brought locally heavy snow to the Tetons. At the Jackson Hole Ski Resort, 15 inches of new snow was measured.
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 30, 3:23 PM MST, 3 hours 37 minutes earlier.
Area Forecast Discussion National Weather Service Riverton WY 423 PM MDT Mon Mar 30 2020 .SHORT TERM...Tonight through Tuesday night Occasional snow showers are occurring mainly over far west Wyoming this afternoon in response to the increasing westerly difluent flow ahead of the digging trough over the Pacific Northwest. Ironically, the snow showers are occurring in an area that currently has the most stable air, so it it leads one to surmise, most of the snow that is occurring in the west is due to moist westerly upslope difluent flow. This snowfall will continue, and become steadier and heavier as the late afternoon and evening wear on as isentropic lift gets underway and we begin to feel the effects of the left front quad of the 125 knot jet. The jet dynamics alone will mainly effect far northwest Wyoming. Earlier runs had the jet a little farther south. We will let the winter storm warning and advisories run their course from 03Z this evening through 05Z Wednesday. The apex of the storm will likely be late tonight and Tuesday morning when all the dynamics come together. The steady snow will continue through Tuesday with the strong westerly difluent upslope flow continuing. The snow will begin to taper off late Tuesday evening with light snow continuing through the rest of Tuesday night. Meanwhile. east of the Divide, including Sweetwater County, 50 to 55 knot winds at 700mb, resulting from the increasing gradient ahead of the approaching PAC NW trough, along with 30 knot winds in the MAV MOS guidance at KCPR and KRKS, has prompted the issuance of a low end high wind warning to be issued from eastern Sweetwater County through Natrona County, including Casper. Areas like Outer Drive just south of Casper will be among the several places that will see occasional 60 mph plus wind gusts out of this event will, which will run from 09Z Tuesday through 03Z Wednesday. This wind event does not exhibit any other dynamics that really stand out. After a warm day east of the Divide Tuesday, the associated cold front will draw in rain showers, first across northern Wyoming, then spreading to areas to the south. The rain showers will turn to snow showers east of the Divide Tuesday night. The Big Horn Mtns will pick up 3 to 5 inches of snow during this time frame, but other areas will remain too mild for much in the way of any accumulation. The aforementioned jet dynamics in northern Wyoming will give the Big Horn mtns a boost with the snowfall. .LONG TERM...(Wednesday through Monday) The GFS/ECMWF models indicate that precip chances should increase across the area on Wednesday, as another short wave moves across the area. Will continue with a minimum of slight chance pops across much of the forecast area. Based upon model trending, it still looks like the eastern and northern areas look more favorable for precipitation. Continued model agreement exists between the GFS/ECMWF models involving the chance of a few inches of snow by Wednesday night. Still a decent amount of model inconsistency due to drier NAM solution from 12Z model runs. By Thursday, the models indicate that a broad and strong upper low is expected to be centered across south-central Alberta. The models further indicate that a trough is expected to be placed into the base of this upper low, and is expected to move across the forecast area Thursday. A strong surface cold front is progged by the models to have moved through the forecast area, with strong cold advection expected across the region. The models are still depicting a decent chance of ongoing snow on Thursday morning especially across the eastern sections of the forecast area. The snow chances are finally expected to decrease by Thursday afternoon and into evening with the passage of the trough axis and upper level jet streak exiting the area. Still uncertain involving snow totals with this system, due to differing solutions involving the trough strength and placement. Nevertheless, expect much below temps with temperatures expected to be around 20 degrees below normal on Thursday and Thursday night. Will keep in a chance of snow in western sections on Friday, with a moist westerly flow setting up across areas especially west of the Divide. Models are still hinting that a shortwave trough could push east across the area on Saturday night. If this solution is correct, there would be chances of snow over the west beginning Saturday and continuing through Saturday night. The progressive and active weather pattern will continue through the rest of the extended forecast period. Some snow could spill east of the Divide Saturday night. Another storm system could occur Sunday or Monday, but models differ significantly involving the solution. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) West of the Continental Divide...KBPI/KJAC/KPNA/KRKS Terminals Will continue with VFR conditions through 06Z in southwest WY. Still expect isolated rain/snow showers between 21Z-06Z tonight. Based upon continuing trends, snow will continue to increase in coverage with areas of MVFR/IFR conditions and some mountain obscuration after 05Z at KJAC and after 11Z Tuesday at KBPI and KPNA. KRKS will remain VFR through the period with a gusty wind this afternoon, tapering off in the evening and then increasing again after 14Z Tuesday. East of the Continental Divide...KCOD/KCPR/KLND/KRIW/KWRL Terminals VFR conditions will occur through the forecast period. TAF sites should see increasing winds and gusts especially after 12Z-14Z Tuesday. KCPR will have a gusty wind until around 01Z tonight, with gradually increasing winds and gusts after 07Z Tuesday through the end of the forecast period. && .FIRE WEATHER... Expect isolated to scattered rain and snow showers will move across western areas into this evening, with continued light precipitation amounts expected. More substantial snow will move in by especially late tonight. Dry conditions will continue east of the Divide with a gusty breeze from Rock Springs through Casper, and light to moderate winds elsewhere. Relative humidity will remain above critical levels. Mixing and smoke dispersal will range from poor in some of the basins to good in the breezier locations. && .RIW WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory from 9 PM this evening to 11 PM MDT Tuesday for WYZ001-002-013-014-023-024. High Wind Warning from 3 AM to 9 PM MDT Tuesday for WYZ019-020- 030. Winter Storm Warning from 9 PM this evening to 11 PM MDT Tuesday for WYZ012. && SHORT TERM...Hattings LONG TERM...Troutman AVIATION...Troutman FIRE WEATHER...Troutman
Hazardous Weather Outlook National Weather Service Riverton WY 316 PM MDT Mon Mar 30 2020 WYZ001>020-022>030-311200- 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- 316 PM MDT Mon Mar 30 2020 This Hazardous Weather Outlook is for Western and Central Wyoming. ...Winter Storm Warnings are in effect for the far west from tonight into Tuesday evening... ...High Wind Warning is in effect from Sweetwater to Natrona Counties from late tonight through Tuesday evening... .DAY ONE...This Afternoon and Tonight...Snow will increase in western Wyoming, with heaviest snow expected after midnight. Please see winter weather products and forecasts for details. Strong winds are expected after midnight tonight in Natrona county and in the Lee of the Absarokas. Please see High Wind Warning and forecasts for details. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday. Moderate to possibly heavy snow is expected across the far west. Strong to high winds are expected for some areas east of the Divide, as well as in Eastern Sweetwater County on Tuesday. Please see highlights and forecasts for details. By Wednesday night...Accumulating snow is possible in some areas east of the divide. .SPOTTER INFORMATION STATEMENT... Spotters are urged to report snowfall amounts. TEAM RIVERTON
Special Weather Statement National Weather Service Riverton WY 341 PM MDT Mon Mar 30 2020 WYZ003-311200- Cody Foothills- Including the cities of Clark, Cody, and Meeteetse 341 PM MDT Mon Mar 30 2020 ...Strong winds possible late tonight and Tuesday morning... * WHAT...West winds 20 to 30 mph with gusts to 50 mph. Locally higher gusts are possible in the vicinity of Clark. * WHERE...The Cody Foothills. * WHEN...Late tonight into Tuesday morning. * ADDITIONAL DETAILS...Motorists should be alert for strong crosswinds if traveling during this time, especially along Highway 120. WYZ025-311200- Upper Green River Basin Foothills- Including the city of Pinedale 341 PM MDT Mon Mar 30 2020 ...Snow showers through this evening, becoming steadier late tonight and Tuesday... * WHAT...Periods of snow. Accumulations of 1 to 3 inches, with higher amounts possible near Bondurant. * WHERE...Upper Green Foothills. * WHEN...Late tonight through Tuesday. * ADDITIONAL DETAILS...Travelers should watch for slick and snow covered roads if traveling during this time frame.| TEAM RIVERTON
The national radar mosaic for the moment the first event began.
1 winter storm. Local standard time, as filed.
At the Jackson Hole Ski Resort, 15 inches of new snow fell.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wyoming in 2020Every state in 2020This day in weather historyWarnings in Wyoming, March 2020
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: 881339.