The highest recorded gusts were 74 mph at Fales Rock and Muddy Gap.
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The episode as NWS RIW wrote it up.
A strong pressure gradient developed ahead of a cold front and produced strong winds in portions of the Green and Rattlesnake Range.The highest recorded gusts were 74 mph at Fales Rock and Muddy Gap.
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 Dec 14, 3:12 PM MST, 8 hours 38 minutes earlier.
Area Forecast Discussion National Weather Service Riverton WY 312 PM MST Wed Dec 14 2016 .SHORT TERM...Tonight Through Saturday Light snow or flurries are falling across much of the far west but the more significant snow will probably not arrive until later this evening as the ridge starts to flatten some and orographics increase. Upglide has saturated the airmass but ridging is likely inhibiting any significant precipitation for now. Strong upglide continues through Thursday/Thursday night ahead of our approaching trough and with a very moist airmass and increasing orographics, we should see significant snow over the entire west. There is still some question on temps in the lowest parts of the Star Valley with h7 temps in the -3c to -4c range although the 18z NAM has trended a little colder. WPC is still sticking with snow and most of the soundings (but not all) are keeping the precip snow so we have upgraded the advisory in the Star Valley to a warning. We already had warning amounts in there so no real change there. We did indicate some uncertainty for the low spots and also the distinct possibility of bigger amounts in the higher spots of the valley and near the foothills. Lull if it occurs in the sw tonight will be short generally 3 to 4 hours before significant precip returns. The nw will keep snow going and the amount of precip the models are putting out around Teton County especially is impressive to say the least (3.5 to 4 inches). Temp profile is not optimal for max dendritic snow crystal growth but length of storm and time heights over the various areas are quite impressive with saturated airmass and deep layered omega. So winter storm warnings out west look good! Clearing behind it Friday night will lead to some bitter cold temps, especially Jackson Valley north to YNP. East of the divide, we still have our warm front lifting nwd overnight with a band of light snow lifting along it. Very strong wind signature is still showing up along the east slope of the Wind River Mountains with 60-80kt winds in the 3-5k layer. Combine that with a potential developing surface low in the Wind River Basin and some upstream stable air, we could see a significant wind event for the east slope of the Wind Rivers carrying over into the wind corridor as strong mid level h7 winds increase over 50kts and then mix down to the surface also. High wind warnings cover these areas from 11 pm tonight to 11 pm Thursday. After that, we deal with our incoming trough from the west and strong arctic front from the north. Storm doesn't last long but there is a window of potential for parts of Central Wyoming with fairly strong QG forcing, upper jet support and possible banding with frontogenesis/divergence couplet over the northern parts. Hard to pinpoint the absolute best area but combination of the all of these initially favors the north late Thursday night/Friday morning and then a little further south during the middle of the day Friday. In addition to the now, the Bighorn Basin and Johnson County will see strong north winds with fropa with falling temps creating bitter cold wind chills. Most areas will at least be in the breezy category with the far north and down wind of the Owl Creeks in the windy category. Cody will have to be watched for winter storm criteria. Johnson possibly especially with wind. WRL and THP are on the edge of the better dynamics and look marginal. Casper looks good for potential winter storm with snowfall amounts, brisk wind and falling temps through the single digits. Probably not in Riverton with Lander looking marginal too. Eventual advisories may be needed from near Big Piney northward possibly not til late Thursday into Friday. The I80 corridor will get interesting behind the arctic cold front Friday afternoon and evening at least with ne wind and a quick blast of snow. Probably 2-4 inches but bitter cold ne wind. Clearing from nw to se late Friday night into Saturday morning will lead to bitter cold temps with recovery very slow on Saturday. .LONG TERM...Saturday Night Through Wednesday Models agree that our winter storm will leave a dry and cold northwest flow across the forecast area through Monday. The biggest issues for those two days are with the temperature forecasts. Concern is that the models are moderating temperatures too much given the expected snow cover. Have tempered the amount of warming and tried to tone things down, especially in the basins east of the Continental Divide. Model differences begin to emerge Tuesday and Wednesday with regard to the next upstream wave as it moves through the Pacific Northwest and dives toward Wyoming. ECMWF wants to return snow to the west Tuesday while the slower GFS holds off until Wednesday. Model blends are trending toward the GFS solution and have therefore limited precipitation chances for Tuesday out west. However, with this next system crossing the forecast area Wednesday have increased precipitation chances all areas particularly in the west. If the GFS is correct, then we would need much higher chances than what is now in the forecast. Nonetheless, given the uncertainty and the time range at least the forecast is trending toward a wetter solution for Wednesday. Temperatures will moderate Tuesday and Wednesday, but are still expected to be below normal. No definitive period of significant wind through the period. && .AVIATION.../00Z ISSUANCE/ West of the Divide...KBPI/KJAC/KPNA/KRKS Terminals Occasional light snow continues along the I-80 corridor between KEVW and KRKS early this afternoon. Conditions will occasionally be IFR at KRKS until 23Z/Wed-01Z/Thu. Warm-frontal type snow band producing this light snow will lift north late this afternoon and early this evening. MVFR to IFR conditions will persist from 00Z-06Z/Thu at KBPI and KPNA, while the snow will begin to decrease between 00Z-03Z/Thu at KRKS. These three terminals should improve to at least low-end VFR after 06Z/Thu with VFR conditions continuing through 00Z/Fri. Could be some light snow showers in the Upper Green River Basin late Thursday afternoon but have just lowered ceilings and included VCSH for now. At KJAC, the snow will increase through the late afternoon hours with little let-up through 18Z/Thu. IFR/LIFR conditions expected after 00Z/Thu with occasional improvement to MVFR. Looks as though there could be some improvement to IFR and possibly MVFR after 20Z/Thu and have trended in that direction. Mountain obscurations, especially across northwest Wyoming, will be widespread. Southwest wind will increase late tonight, but the strongest winds are not likely to reach the surface. However, the expectation is for LLWS in the lowest 1,000 to 1,500 feet, particularly at KBPI. Only significant impact from the wind will probably be BLSN at KJAC Thursday morning with potential for further reduction in visibility. East of the Divide...KCOD/KCPR/KLND/KRIW/KWRL Terminals VFR conditions are anticipated through about 01Z/Thu before snow band associated with north-moving cold front moves across central Wyoming. Looks difficult to get much snow or MVFR conditions at KRIW and KLND as this wave lifts north. However, it does appear KCPR will fare better between about 02Z-08Z/Thu with the best chance between 04Z-07Z/Fri. Have IFR conditions during this 6-hour period. Wave continues to lift north through KWRL and KCOD with MVFR and IFR conditions possible, respectively. Mountain obscurations will be frequent during the 02Z-10Z timeframe. Also expect southwest wind to increase late tonight. While the strongest winds are not likely to reach the surface except at KCPR, the stage is set for LLWS in the lowest 1,000 to 1,500 feet. KCOD and KLND will be particularly susceptible to LLWS of 40-50kts. Have 20-30kt surface wind in KCPR forecast by 12Z/Thu with these winds continuing through at least mid-afternoon Thursday. && .FIRE WEATHER... Low fire danger continues with snow out west through Friday and a period of light snow east tonight and a significant storm for late Thursday Night through Friday evening. It will be windy tonight through Thursday across the Green Mountains/Rattlesnake Ranges and in the Wind River mountains. && .RIW WATCHES/WARNINGS/ADVISORIES... High Wind Warning from 11 PM this evening to 11 PM MST Thursday for WYZ015-019. Winter Storm Watch from late Thursday night through Friday evening for WYZ003>007-010-011-015-017>020-022. Winter Storm Warning until 5 PM MST Friday for WYZ001-002- 012>014-023>025. Winter Weather Advisory from 5 PM this afternoon to midnight MST Friday night for WYZ016. Winter Storm Warning from 11 PM this evening to midnight MST Friday night for WYZ008-009. && SHORT TERM...Skrbac LONG TERM...CNJ AVIATION...CNJ FIRE WEATHER...Skrbac
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE RIVERTON WY 215 PM MST WED DEC 14 2016 WYZ001>020-022>030-151200- 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- 215 PM MST WED DEC 14 2016 ...NUMEROUS WINTER STORM AND HIGH WIND PRODUCTS FOR A MAJOR WINTER STORM IMPACTING THE WEST THIS AFTERNOON THROUGH FRIDAY, AND THE EAST MAINLY THURSDAY NIGHT INTO FRIDAY NIGHT... THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN AND CENTRAL WYOMING. .DAY ONE...TODAY AND TONIGHT SIGNIFICANT SNOW DEVELOPING OVER WESTERN WYOMING THIS AFTERNOON AND BECOMING MORE WIDESPREAD AND HEAVIER THIS EVENING. STRONG TO HIGH WINDS OVER THE EASTERN SLOPES OF THE WIND RIVER MOUNTAINS AND SOUTHEAST FREMONT COUNTY. PLEASE SEE THE WINTER WEATHER AND HIGH WIND PRODUCTS FOR MORE DETAILS. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY THURSDAY AND FRIDAY...SIGNIFICANT WINTER STORM CONTINUES OVER WESTERN WYOMING. AN ARCTIC COLD FRONT WILL DROP SOUTH...EAST OF THE DIVIDE THURSDAY NIGHT. THIS WILL RESULT IN SHARPLY COLDER AIR AND THE POTENTIAL FOR SIGNIFICANT SNOWFALL IN SOME LOCATIONS EAST OF THE DIVIDE LATE THURSDAY NIGHT THROUGH MUCH OF FRIDAY NIGHT. HIGH WINDS CONTINUE OVER THE EAST SLOPE OF THE WIND RIVER...GREEN MOUNTAINS AND RATTLESNAKE RANGE THROUGH THURSDAY EVENING. SATURDAY AND SUNDAY...BITTERLY COLD...WITH TEMPERATURES 20 TO 30 DEGREES BELOW AVERAGE. .SPOTTER INFORMATION STATEMENT... SPOTTERS ARE ENCOURAGED TO REPORT ANY SNOWFALL BY CALLING 1-800-211-1448.
The national radar mosaic for the moment the first event began.
1 high wind. Local standard time, as filed.
There were many wind gusts exceeding 58 mph across the region. The highest recorded gusts were 74 mph at Beaver Rim and Fales Rock.
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, December 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: 665833.