Strong west to southwest gap winds developed over portions of the central and southern Laramie Range, as well as the north Snowy Range foothills.
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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 CYS wrote it up.
Strong west to southwest gap winds developed over portions of the central and southern Laramie Range, as well as the north Snowy Range foothills.
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 Cheyenne, WY wrote its last area forecast discussion before the first event at Jan 27, 9:06 PM MST, 4 hours 24 minutes earlier.
Area Forecast Discussion National Weather Service Cheyenne WY 906 PM MST Sat Jan 27 2018 .UPDATE... Issued at 900 PM MST Sat Jan 27 2018 This evening/s update will focus on high winds for tonight and Sunday morning. WYDOT sensors along the I-80 wind corridor indicated a gradual uptick in sustained winds and gusts between mile markers 250 and 290. The surface pressure pattern shown by the GFS and NAM keeps the trough along the I-25 corridor through 18Z Sunday, with the favorable 3-5mb gradient between Arlington and Bordeaux. 800mb winds peak between 50 and 55 kt in this area. Confidence of a high wind event for I-25 corridor between Wheatland and Chugwater is moderate at best. Cancelled the High Wind Watch for WY zone 106, but cannot rule out some gusts of 45 to 55 mph late tonight and early Sunday morning. The High Wind Warning remains in effect for WY zone 110. There will be patchy blowing snow creating icy patches ob area roadways. && .SHORT TERM...(This evening through Monday) Issued at 205 PM MST Sat Jan 27 2018 Main forecast concern this weekend and into Monday will be winds, mainly across the wind corridors along portions of I-80 and I-25. Winds have already started to increase across the Arlington/Elk Mountain areas this afternoon, likely due to llvl mixing. With gradients expected to increase tonight, upgraded the High Wind Watch to a warning through Sunday morning. There will be a lull in the winds this evening, but expect them to increase later in the evening as the llvl gradients re-intensify. Less confident with SW Platte county (Bordeaux) and the I-80 Summit, mainly because the high res models are showing the surface lee-side trough a little too far west along the Laramie Range. This surface trough quickly exits the area to the east, instead of translating southeast over time which would be more favorable for strong winds on the I-80 summit. Decided to keep the watch going for Bordeaux, just in case high res models have misplaced the position lee-side trough. Otherwise, mountain snow will increase in coverage tonight with some snow developing over the lower elevations near Saratoga and Elk Mountain/Arlington by early Sunday morning. Increased POP in these areas with some light accumulation. Added Blowing snow to the forecast as well with strong west to southwest winds expected. Can not rule out a Winter Weather Advisory for the higher ridges and peaks of the Snowy and Sierra Madre Range in addition to the stretch of I-80 between Laramie and Rawlins due to blowing snow, but not terribly confident about how much snow will fall at this time since the last few mountain events failed to produce much snowfall. Increased low temperatures tonight and Sunday night to account for thick mid to high cloud cover. Slight warming trend will continue into Sunday, but do not expect temperatures to get all that mild due to the cloud cover during the day. West to northwest winds will spread out into the high valleys and high plains, with gusts between 40 to 50 mph expected into the western Nebraska panhandle. Strong winds will be less of concern through Sunday night since winds just off the surface will shift into the northwest through the night which is not a favorable direction for strong gap winds. With a bit less cloud cover on Monday, expect temperatures in the mid 40's to low 50's across the area during the afternoon. .LONG TERM...(Monday night through Friday) Issued at 330 AM MST Sat Jan 27 2018 Monday night...Somewhat mild night on tap with surface lee troughing leading to decent surface mixing and wind, and thus minimum temperatures in the mid 20s to lower 30s. Tuesday...Prefrontal warming ahead of the approaching cold front will help boost maximum temperatures into the 50s east of I-25, aided by downslope warming winds. Wednesday...Considerably cooler and windy as a potent shortwave trough aloft and its associated baroclinic band and cold front move across our counties. With adequate low and mid level moisture, will see scattered snow showers in the cyclonic flow aloft under the upper jet and with the baroclinic band passage. Thursday...Cold and blustery day with extensive cloud cover under cyclonic flow aloft and with the Canadian surface high covering our counties, and with 700 mb temperatures progged to be near -20 Celsius, high temperatures may struggle to climb out of the 20s. All models show adequate low and mid level moisture, frontogenesis, and upslope flow late Wednesday night and Thursday, resulting in 6 to 12 hours of light to moderate snow. Increased POP as the front stalls near the mountains. Friday...Slow warming trend as the airmass moderates with rising thicknesses and less cloud cover. Windy day with progged low and mid level gradients. && .AVIATION...(For the 06Z TAFS through 06Z Sunday night) Issued at 843 PM MST Sat Jan 27 2018 VFR with lowest CIGS around 5000 ft AGL. The Snowy and Sierra Madre mountains will be obscured by lower CIGS in snow showers. Windy conditions will exist for most of southeast Wyoming through Sunday with west to northwest winds gusting to 40 kt. Periodic mountain wave turbulence with localized gusts to 50 kt may also occur. Surface winds will be lighter for the Nebraska Panhandle tonight, becoming breezy from the northwest with gusts to 30 kt Sunday. && .FIRE WEATHER... Issued at 107 PM MST Sat Jan 27 2018 No Fire Weather concerns with a surface snow pack across most of the area in addition to high relative humidites and several chances for snowfall by late next week into next weekend. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...High Wind Warning until 10 AM MST Sunday for WYZ110. NE...None. && UPDATE...MAJ SHORT TERM...TJT LONG TERM...RUBIN AVIATION...MAJ FIRE WEATHER...TJT
Hazardous Weather Outlook National Weather Service Cheyenne WY 1242 AM MST Sun Jan 28 2018 NEZ002-003-019>021-054-055-095-096-290415- Dawes-Box Butte-Scotts Bluff-Banner-Morrill-Kimball-Cheyenne- North Sioux-South Sioux- 1242 AM MST Sun Jan 28 2018 This hazardous weather outlook is for the western Nebraska Panhandle. .DAY ONE...TONIGHT No hazardous weather is expected at this time. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY The probability for widespread hazardous weather is low. .Spotter information statement... Spotter activation will not be required at this time. WYZ101>119-290415- Converse County Lower Elevations-Niobrara County- North Laramie Range-Ferris/Seminoe/Shirley Mountains- Shirley Basin-Central Laramie Range and Southwest Platte County- East Platte County-Goshen County-Central Carbon County- North Snowy Range Foothills-Southwest Carbon County- Sierra Madre Range-Upper North Platte River Basin-Snowy Range- Laramie Valley-South Laramie Range-South Laramie Range Foothills- Central Laramie County-East Laramie County- 1242 AM MST Sun Jan 28 2018 This hazardous weather outlook is for portions of east central Wyoming...south central Wyoming and southeast Wyoming. .DAY ONE...TONIGHT A High Wind Warning is in effect until 10 am for Arlington, Elk Mountain, Bordeaux, Vedauwoo and the I-80 Summit between Laramie and Cheyenne. Expect west to southwest winds of 35 to 45 mph with gusts to 65 mph. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY Winds will diminish from late Sunday morning through Sunday afternoon. Colder temperatures and accumulating snowfall are expected late Wednesday night through Friday. .Spotter information statement... Spotter activation will not be required at this time.
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHEYENNE WY
820 PM MST SAT JAN 27 2018
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0811 PM NON-TSTM WND GST ARLINGTON 41.59N 106.21W
01/27/2018 M57 MPH CARBON WY DEPT OF HIGHWAYS
0811 PM NON-TSTM WND GST 14 NE CENTENNIAL 41.44N 105.92W
01/27/2018 M51 MPH ALBANY WY DEPT OF HIGHWAYS
&&
BCHAPMANPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHEYENNE WY
1206 AM MST SUN JAN 28 2018
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1130 PM NON-TSTM WND GST 1 SSE BORDEAUX 41.93N 104.94W
01/27/2018 M59 MPH PLATTE WY DEPT OF HIGHWAYS
BORDEAUX WYDOT SITE. SUSTAINED WINDS 40 MPH.
&&
GCLAYCOMThe national radar mosaic for the moment the first event began.
9 high wind. Local standard time, as filed.
The WYDOT sensor at Buford East measured sustained winds of 40 mph or higher, with a peak gust of 58 mph at 28/0410 MST.
The WYDOT sensor at Halleck Ridge measured sustained winds of 40 mph or higher.
The WYDOT sensor at Bordeaux measured sustained winds of 40 mph or higher.
The WYDOT sensor at Lone Tree measured sustained winds of 40 mph or higher.
The WYDOT sensor at Arlington East measured peak wind gusts of 58 mph.
The UPR sensor at Buford West measured a peak wind gust of 60 mph.
The WYDOT sensor at Cooper Cove measured sustained winds of 40 mph or higher.
The WYDOT sensor at Interstate 80 mile post 249 measured peak wind gusts of 58 mph.
The WYDOT sensor at Arlington measured peak wind gusts of 58 mph.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wyoming in 2018Every state in 2018This day in weather historyWarnings in Wyoming, January 2018
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: 734048, 734054, 734047, 734050, 734051, 734049, 734053, 734055, 734052.