A combination of strong mid-level winds blowing down the east slopes of the mountains and an approaching cold front produced strong winds across portions of northern and central Wyoming on Sunday morning, October 16. The strongest winds occurred in the Absaroka Mountains and along the Cody Foothills.
Every event with a place to put it; 3 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 combination of strong mid-level winds blowing down the east slopes of the mountains and an approaching cold front produced strong winds across portions of northern and central Wyoming on Sunday morning, October 16. The strongest winds occurred in the Absaroka Mountains and along the Cody Foothills. A mesonet sensor near the summit of Chief Joseph Highway recorded a maximum wind gust of 85 mph, while in the foothills west of Clark the peak gust was 77 mph. Strong winds also briefly developed across the Lander Foothills with a peak gust to 64 mph registered at Hunt Field in Lander at 0916MST.
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 Oct 16, 1:32 AM MST, 4 hours 19 minutes earlier.
Area Forecast Discussion National Weather Service Riverton WY 232 AM MDT SUN OCT 16 2016 .SHORT TERM...Today through Tuesday night ...High Wind Warning for portions of central and northern Wyoming this morning... ...Winter Weather Advisory for the west central and southwestern mountains and foothills tonight through Monday... Imagery shows a large deep broad upper level trof across the EPAC and western CONUS. An accompanying jet of 120+ kts will also arrive by this morning along with decent upper level divergence and associated lift. Current surface obs show a strong north south oriented Pacific cold front over the western CONUS with a weak stationary front lying against the spine of the Divide across Wyoming. Light precipitation (snow above 10000 feet) falling across portions of western Wyoming. Today through Monday: Modest moisture and relatively warm temperatures this morning and through much of the day today will keep accumulating snow levels on the high side mainly above 9500 feet until this evening when colder air aloft arrives and snow levels drop to valley floor level overnight. Heaviest precipitation/snowfall coincide with the arrival of the nose of the jet and slightly better moisture. The western mountains, including the Salt, Wyoming and Tetons ranges, in addition to the Wind River mountains and Upper Green River foothills will be the areas most favored for significant snowfall from Sunday night through the day on Monday. A Winter Weather Advisory has been issued for these locations and over that time period reflecting 6 to 12 inches of snow accumulation mainly above 8000 feet in the mountains and 2 to 6 inches in the foothills of the Upper Green River. Additionally this morning...a number of atmospheric conditions, such as amplified mountain waves, increasing flow aloft, warm surface lee side temperatures and a tightening surface pressure gradient come together to give high wind at times over the foothills of the region and across the wind corridor. A High Wind Warning has been continued/issued through this morning. High wind will again be possible on Monday across the foothills and the wind corridor...but will not issue a watch at this point as may be confusing with current Warning. Monday night through Tuesday night: The stronger portion of the upper jet moves east of the FA although the body of the jet (100+kts) will remain flowing over much of the southern portion of Wyoming. Available moisture will decrease some as the flow goes nearly zonal Monday night through most of the morning Tuesday before the main trof axis approaches/arrives across western Wyoming Tuesday afternoon and evening with increased moisture and dynamics producing more snowfall across the western mountains. ATTM is appears that snowfall totals with this portion of the system will remain below advisory levels...but worth watching and monitoring. .LONG TERM...Wednesday through Sunday Synopsis...Cool and unsettled conditions will remain over the area Wednesday as an upper trough slowly exits east. Isolated to scattered rain and snow showers over the north and central will diminish Wednesday evening. A ridge of high pressure will bring dry weather with a warming trend Thursday and Friday. A mainly dry cold front will bring a slight cooling trend late next weekend. Discussion...Synoptic pattern at the beginning of this period consists of deepening upper low over the Gulf of Alaska, downstream ridging over the Intermountain West and upper trough over the high plains. GFS remains slower than ECMWF with progression of upper trough into the plains Wednesday with ECMWF trending slower - toward GFS over the last few runs. Best instability across the eastern third of Wyoming on Wednesday with rain and snow showers expected to be most numerous across Johnson and Natrona counties. Cold air aloft (-6c at H7, -24c at H5) will likely result in some snow pellet showers across the lower elevations. Broad ridge over the Rockies and southwest U.S. will bring temperatures into above normal range across the area Friday and Saturday. Both GFS and ECMWF show a fast moving shortwave along the U.S./Canadian border Saturday/Saturday night which looks to be mainly dry for our area, possibly kicking winds across the wind corridors Saturday, and pushing a dry Canadian cold front south across the area Saturday night and Sunday. && .AVIATION.../12Z ISSUANCE/ WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES Valley rain and high mountain snow with snow levels dropping a little bit this morning. Areas of MVFR conditions will occur through this morning, including KJAC airport until 18Z. VFR conditions will occur at the rest of the terminal sites. Scattered precipitation will continue through the afternoon. After 00Z, rain and mountain snow will move back into the west with MVFR conditions prevailing by 06Z Monday. Strong wind aloft over the mountains will cause considerable mountain turbulence through the period. EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES Breezy to windy conditions along with mountain turbulence and low level wind shear today. Most of the shower activity will remain along and west of the Divide today. Mountain tops will be obscured at times due to this activity. Otherwise VFR conditions will prevail today and tonight. The wind will decrease after 00Z in most locations. && .FIRE WEATHER... Fire danger low to moderate all areas today...lasting through the beginning of the work week...as minimum RH values remain above 25 percent over those areas in central Wyoming where fuels remain critical. That said, a vigorous upper level weather system will begin to influence the forecast area today with increasing precipitation west of the Divide and strong winds east of the Divide today and Monday in the foothills and across the wind corridor between South Pass and Casper. Winds could gust as high as 50 to 60 mph at times. && .RIW Watches/Warnings/Advisories... High Wind Warning until noon MDT today for WYZ003-018>020. Winter Weather Advisory from 6 PM this evening to 6 PM MDT Monday for WYZ012-014-024-025. && SHORT TERM...Braun LONG TERM...AEM AVIATION...AR FIRE WEATHER...Braun
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE RIVERTON WY 234 AM MDT SUN OCT 16 2016 WYZ001>020-022>030-171100- 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- 234 AM MDT SUN OCT 16 2016 ...HIGH WIND WARNING FOR THE CODY FOOTHILLS...THE LANDER FOOTHILLS...AND THE GREEN MOUNTAINS OVER TO CASPER THIS MORNING... ...WINTER WEATHER ADVISORY FOR PORTIONS OF WESTERN AND SOUTHWESTERN WYOMING TONIGHT THROUGH MONDAY... THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN AND CENTRAL WYOMING. .DAY ONE...TODAY AND TONIGHT TODAY AND TONIGHT...STRONG WEST TO SOUTHWEST WIND ACROSS THE CENTRAL WIND CORRIDOR BETWEEN SOUTH PASS AND CASPER IN ADDITION TO THE LANDER AND CODY FOOTHILLS. SNOW IN THE WESTERN MOUNTAINS...INCREASING IN INTENSITY TONIGHT WITH MODERATE TO HEAVY SNOW AT TIMES. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY MONDAY...A STRONG WINTER WEATHER SYSTEM CONTINUES TO PUSH ACROSS THE REGION WITH MODERATE TO LOCALLY HEAVY SNOW AT TIMES WEST OF THE DIVIDE. STRONG WINDS AND BLOWING SNOW WILL BE POSSIBLE ACROSS THE WESTERN MOUNTAINS...WITH HIGH WINDS POSSIBLE ALONG THE EASTERN FOOTHILLS AND PORTIONS OF CENTRAL WYOMING. TUESDAY AND WEDNESDAY...SCATTERED TO NUMEROUS SNOW SHOWERS OVER THE WESTERN MOUNTAINS TUESDAY AFTERNOON WITH CHANCES OF RAIN AND SNOW SHOWERS SPREADING INTO CENTRAL AREAS TUESDAY NIGHT AND WEDNESDAY. .SPOTTER INFORMATION STATEMENT... SPOTTERS SHOULD REPORT WIND GUSTS PAST 45 MPH...WIND DAMAGE AND SNOWFALL. THANK YOU.
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE RIVERTON WY 119 AM MDT SUN OCT 16 2016 WYZ001-162200- YELLOWSTONE NATIONAL PARK- INCLUDING THE CITIES OF...LAKE...MAMMOTH...OLD FAITHFUL 119 AM MDT SUN OCT 16 2016 A LARGE STRONG UPPER LEVEL WEATHER SYSTEM WILL BRING INCREASED CHANCES FOR ACCUMULATING SNOWFALL OVER THE NEXT FEW DAYS AS SNOW LEVELS SLOWLY DROP. EXPECT A TRACE TO 2 INCHES FOR MOST LOCATIONS TODAY...WITH UP TO 3 OR 4 INCHES ACROSS THE HIGHEST ELEVATIONS IN THE PARK. TONIGHT THROUGH THE DAY MONDAY WILL SEE AN INCREASE IN SNOWFALL...WITH BETWEEN ONE AND SIX INCHES OF NEW ACCUMULATION FOR MOST LOCATIONS THROUGH THE DAY MONDAY. WYZ002-162200- ABSAROKA MOUNTAINS- 119 AM MDT SUN OCT 16 2016 A LARGE STRONG UPPER LEVEL WEATHER SYSTEM WILL BRING INCREASED CHANCES FOR ACCUMULATING SNOWFALL OVER THE NEXT FEW DAYS AS SNOW LEVELS SLOWLY DROP. EXPECT A TRACE TO 2 INCHES FOR MOST LOCATIONS TODAY...WITH UP TO 3 OR 4 INCHES ACROSS A FEW OF THE HIGHER ELEVATIONS IN THE SOUTHERN MOUNTAINS. TONIGHT THROUGH THE DAY MONDAY WILL SEE AN INCREASE IN SNOWFALL...ESPECIALLY ACROSS THE SOUTHERN MOUNTAINS WITH BETWEEN ONE AND SIX INCHES OF NEW ACCUMULATION FOR MOST LOCATIONS THROUGH THE DAY MONDAY. WYZ013-023-162200- JACKSON HOLE-STAR VALLEY- INCLUDING THE CITIES OF...JACKSON...AFTON...ALPINE... STAR VALLEY RANCH...THAYNE 119 AM MDT SUN OCT 16 2016 A LARGE STRONG UPPER LEVEL WEATHER SYSTEM WILL BRING INCREASED CHANCES FOR ACCUMULATING SNOWFALL OVER THE NEXT FEW DAYS AS SNOW LEVELS SLOWLY DROP. EXPECT A TRACE AN INCH FOR MOST VALLEY LOCATIONS TODAY. TONIGHT THROUGH THE DAY MONDAY WILL SEE AN INCREASE IN SNOWFALL WITH BETWEEN ONE AND THREE INCHES OF NEW ACCUMULATION FOR MOST LOCATIONS THROUGH THE DAY MONDAY....WITH A FEW PREFERRED LOCATIONS GETTING UP TO 4 INCHES. WYZ026-027-162200- UPPER GREEN RIVER BASIN-SOUTH LINCOLN COUNTY- INCLUDING THE CITIES OF...LA BARGE...BIG PINEY...FARSON... KEMMERER...COKEVILLE 119 AM MDT SUN OCT 16 2016 A LARGE STRONG UPPER LEVEL WEATHER SYSTEM WILL BRING INCREASED CHANCES FOR ACCUMULATING SNOWFALL OVER THE NEXT FEW DAYS AS SNOW LEVELS SLOWLY DROP. EXPECT A TRACE TO AN INCH OF SNOWFALL TODAY. TONIGHT THROUGH THE DAY MONDAY WILL SEE AN INCREASE IN SNOWFALL WITH BETWEEN ONE AND TWO INCHES OF NEW ACCUMULATION FOR MOST LOCATIONS THROUGH THE DAY MONDAY....WITH A FEW PREFERRED LOCATIONS NEAR THE MOUNTAINS GETTING 3 TO 4 INCHES.
The national radar mosaic for the moment the first event began.
3 high wind. Local standard time, as filed.
The wind sensor 5 miles west of Clark recorded several wind gusts past 58 mph including a maximum gust of 77 mph.
Several wind gusts past 80 mph were recorded along the Chief Joseph highway including a maximum gust of 85 mph.
A peak wind gust to 64 mph was recorded at the Lander Airport at 0916MST.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wyoming in 2016Every state in 2016This day in weather historyWarnings in Wyoming, October 2016
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: 658961, 658960, 658962.