A strong late winter Pacific storm brought heavy snow, heavy rain and strong winds which closed roads across southeastern Idaho. Reports of flooding and wind damage also occurred.
Every event with a place to put it; 31 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 PIH wrote it up.
A strong late winter Pacific storm brought heavy snow, heavy rain and strong winds which closed roads across southeastern Idaho. Reports of flooding and wind damage also occurred.
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 Pocatello, ID wrote its last area forecast discussion before the first event at Mar 9, 1:50 PM MST, 10 minutes earlier.
Area Forecast Discussion National Weather Service Pocatello ID 150 PM MST Thu Mar 9 2023 .SHORT TERM...Tonight through Friday night. A low pressure system centered off the NW coast early this afternoon will direct a strong inland penetrating Atmospheric River into SE Idaho tonight through Friday. The low off the NW coast will advance east along the Canadian border Friday afternoon and night with an associated cold front pushing from west to east across the region during the afternoon and evening hours sweeping much of the Atmospheric River moisture south and east of the region by Saturday morning. Ahead of this frontal boundary we will see heavy snowfall across most of the SE Idaho mountains and the front range and upslope valley locations leading into the CNTRL mountains from Richfield to Howe. Further south, we will see very strong downslope winds across the southern highlands and along the Interstate corridor from Pocatello to Burley. Wind gusts exiting from the southern mountain valleys will likely reach 60 mph in a number of locations. To complicate matters, warming temperatures and rising snow levels ahead of the cold front Friday afternoon will encourage the development of rain in the Snake River Plain as far north as Ashton. Thankfully the heaviest precipitation in the Snake River Plain will likely accompany the front along with colder temperatures late Friday afternoon with rain changing over to snow fairly rapidly. And finally, there does appear to be some instability associated with the frontal passage Friday afternoon up along the Montana border where we may see some brief but intense convective bands moving through the upper Upper Snake River Plain and Highlands. By Saturday morning, the storm will have passed east of the region with NW flow aloft encouraging light snowfall activity in the upslope regions of the CNTRL and ERN mountains. Huston .LONG TERM...Saturday through next Thursday. Saturday and most of Sunday will be a quiet weather period before our next system arrives. Only slight chances for light mountain snow will continue Saturday and Sunday as models feature a weak transient ridge building in through Monday. Meanwhile, a series of lows will rotate along the coast of Washington, with an associated trough moving inland late Monday/Tuesday morning. This combination of features and synoptic setup will result in favorable flow for the advection of moisture into the region, marking our next atmospheric river event, which will occur Monday through Wednesday. A prolonged period of southerly flow across our southern zones will result in a warming trend throughout much of the extended period. Daily highs in the low to mid-40s will mean rain or rain/snow mix as far north as the upper Snake Plain Monday and Tuesday. GEFS is currently running a bit higher than EPS with regard to mean 24-hour snow totals for the Monday through Tuesday evening timeframe, with a mean of 4"-10" across the central Idaho mountains and valleys and 2"-6" for the eastern and southeast highlands. For this same period, The National Blend is indicating a 30-80% probability of 8 or more inches for much of the central mountains and up to a 60% probability of 4 or more inches across the Centennials, Big Holes and Bear River Range. The NBM only shows around a 40% chance that the southern highlands will see 2". The potential for flooding will persist considering additional rainfall and snowmelt following the event on Friday. Come Thursday, high pressure will begin to build in again as snow showers exit to the northeast. Cropp && .AVIATION...Precipitation will overspread the region from west to east, beginning around 4z tonight. Hi-res models show the heaviest precipitation moving through 5z-12z, with another potent round after 15z tomorrow. All sites will see snow at the onset, with precipitation switching over to rain by late morning to early afternoon at KBYI, KPIH, and KIDA. Winds will begin to increase this evening and peak during the afternoon tomorrow, with S/SE winds over 20 kts and gusts exceeding 40 kts. Expect reductions in VIS to IFR due to snow and even blowing snow at times, with the blowing risk especially high at KDIJ. Cropp && .HYDROLOGY... Atmospheric river moisture and strong southerly flow will bring afternoon highs Friday to near 50 in the Burley area and low- to mid- 40s across the Snake River Plain. Warmer temperatures coupled with rain and strong winds may lead to an increased potential for snow- melt flooding across lower elevations. Early indications suggest the most likely area for snow-melt flooding would be south of Burley through Oakley. If you live along the Interstate 84/86 corridor, you may want to exercise extra precautions now and move heavy snow accumulations away from the foundation of your home and ensure storm drains are cleared. MacKay/Huston && .PIH WATCHES/WARNINGS/ADVISORIES... Winter Storm Warning from 9 PM this evening to 5 AM MST Saturday for IDZ051-052-068-069-071>075. Winter Weather Advisory from midnight tonight to 9 PM MST Friday for IDZ053-065-070. High Wind Warning from midnight tonight to 9 PM MST Friday for IDZ054>057. Winter Storm Warning from midnight tonight to 5 AM MST Saturday for IDZ058-060-062>064-066-067. Winter Weather Advisory from midnight tonight to 5 AM MST Saturday for IDZ059-061. &&
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE POCATELLO ID
812 AM MST THU MAR 9 2023
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0811 AM SNOW 2 N MACKS INN 44.52N 111.33W
03/09/2023 M4.5 INCH FREMONT ID TRAINED SPOTTER
4.5 INCHES OF SNOWFALL SINCE 5PM YESTERDAY.
VISIBILITY 3/4 MILE.
&&
MHPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE POCATELLO ID
1002 AM MST THU MAR 9 2023
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0955 AM SNOW ASHTON 44.07N 111.45W
03/09/2023 M4.0 INCH FREMONT ID EMERGENCY MNGR
OVERNIGHT SNOW TOTAL.
&&PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE POCATELLO ID
100 PM MST THU MAR 9 2023
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1255 PM SNOW TETON 43.89N 111.68W
03/09/2023 M1.8 INCH FREMONT ID TRAINED SPOTTER
OVERNIGHT SNOW TOTAL.
&&The national radar mosaic for the moment the first event began.
13 winter storm, 13 avalanche, 5 high wind. Local standard time, as filed.
The Bern COOP observer reported 6 inches of snow and multiple avalanches occurred in the region with the strong winds.
Strong winds and snowfall caused blowing snow and US Highway 26 to close from Arco to Carey. Widespread wind gusts in the 60 to 70 mph range were recorded. 40 miles west of Idaho Falls recorded 6 inches of snow via the COOP observer.
A strong cold front brought heavy snow and high winds and extensive travel difficulties on the 10th. US Highway 26 closed between Arco and Carey. Wind gusts over 50 mph were widespread with a 62 mph gust measured at Dead Man Canyon and over 50 mph measured at Howe, Arco and Berenice. Snowfall totals were measures at 9 inches at Moore and 8 inches at Arco and Mackay.
A strong Pacific cold front brought heavy snow and 50 mph wind gusts. seven miles south southeast of Obsidian measured 19 inches of snow and the Stanley COOP observer measured 7.6 inches. A 55 mph wind gust was measured at Horton Peak.
Heavy snow and strong winds caused extensive avalanche activity in the Wood River area with the following snow amounts: Hailey 18 inches, Bellevue 12.5 inches, Picabo 10 inches. Wind gusts were 62 mph at Gannett and 49 mph at Picabo.
Wind gusts of 50 to 65 mph combined with snowfall closed interstate 15 from Dubois to the Montana state line on the 10th. The Dubois COOP site measured 4.8 inches of snow with the storm system.
Forty-five to 55 mph wind gusts were widespread on the 10th and combined with heavy snow to close US Highway 20 between Ashton and the Montana state line and Idaho Highway 87 fromn Island Park to the Montana state line. The Island Park COOP site recorded 7.4 inches of snow and 12 inches fell at Macks Inn.
A strong Pacific storm brought heavy snow and strong winds. The Inkom COOP observer measured 6 inches of snow and the Downey COOP observer measured 4.6 inches. Wind gusts were 50 to 60 mph with 52 mph at Fish Creek and 51 mph near Lava Hot Springs measured on the afternoon of the 10th.
Heavy snow and strong winds occurred with the passage of a strong Pacific cold front. 18 inches of snow fell in Ketchum with 12 to 16 inches in Sun Valley. Highway 75 was closed in both directions over Galena Pass. A wind gust of 64 mph was measured 4 miles west of Galena and 55 mph 7 miles northwest of Ketchum.
A strong Pacific cold front brought strong winds and heavy snow to the region. US Highway was closed from Carey to Arco on the 10th due to the snow and wind. The Richfield COOP site recorded 6 inches of snowfall. Wind gusts of 51 mph were measured at Potter Butte and 11 miles north of Shoshone. Richfield had a 49 mph wind gust. The wind gusts caused power outages and 2,500 customers were without power in the Shoshone and Kimama areas.
The Cotton Ridge RAWS measured a 70 mph wind gust. The public measured 62 mph in Elba and 55 mph in Albion.
Another in a series of strong Pacific storm systems brought more extremely strong winds and blowing snow which caused the closing of US Highway 20 from Ashton to the Montana state line, Idaho Highway 33 from Newdale to Tetonia, and Idaho Highway 32 from Ashton to Tetonia. Wind gusts reached 72 mph in Clementsville68 mph in Felt, and 55 mph in Victor.
Strong winds and snowfall with a Pacific storm system closed Idaho Highway 33 from Newdale to Tetonia. 2 to 4 inches of snow fell in the Idaho Falls area. Wind gusts were widespread at 50 to 70 mph with a peak of 67 mph at the Idaho Falls Airport ASOS. 66 mph was measured at Roberts and 61 mph at Rexburg. The winds caused some damage with many tree limbs down, traffic lights hanging in Idaho Falls, wires down in Ammon, gas station sign blown down in Rexburg.
Canyon Creek measured a 64 mph wind gust at 930 AM MDT on the 10th and several gusts over 50 mph occurred at Pine Creek.
Fifty to 60 mph winds combined with snow to cause extremely hazardous driving conditions. Soda Springs recorded 5 inches of snow with a 58 mph wind gust measured at Galbraith and 50 mph gusts at Pole Canyon, Lund and Niter.
Wind gusts of 55 to 70 mph were widespread with a peak of 66 mph 9 miles west of Black Pine. 63 mph gusts were measured at Idahome, Pilot Gold and Moburg Canyon. Snow also fell with 3 inches measured at Rockland.
Multiple wind gusts of 50 to 75 mph occurred on the 10th in association with a Pacific storm system and a strong cold frontal passage. The Burley Municipal Airport had gusts of 66 and 68 mph 4 hours apart at around 0730 adn 1130 MDT. Rupert measured 75 mph. Two semi tractor trailers blown over at different locations on interstate 86 between exit 15 and 33. A metal shid blown off foundation and down the block in Rupert. Another smi tractor trailer blown over in the median along interstate 84 near Burley. Widespread power outages were reported as well.
Wind gusts of 60 to 80 mph were widespread ahead of a cold front. The maximum was 76 mph at the Pocatello Airport ASOS at 856 AM MDT. Other gusts were 71 mph at American Falls, 69 mph at Fort Hall, 62 mph in Chubbuck, and 58 mph in Aberdeen. Nearly 2,000 customers suffered power outages. Sheet metal blew off roof of Master Mechanix in Pocatello. Lrge evergreen tree 2 foot in diameter uprooted in American Falls, Street light pole blown over on Pocatello Creek Rd in Pocatello, Tree limbs down, shids blown over, shingles blown off on northwest side of Chubbuck,l Lagre highway sign downed at interstate 86 Pocatello Airport exit.
An avalanche 5 miles south of Dingle closed Merkley Lake Road.
Avalanche blocked Big Wood River near River Trail and Empty Saddle Trail. 2 homes hit and some flooding.
Avalanche struck 2 homes on War Eagle Dr near Della Vista Dr. Two homes impacted one with minor damage and the other significant with snow breaking through windows and doors leaving piles of snow up to 3 feet deep. Water backed up on War Eagle Dr to 1 foot after debris piles in Big Wood river were 15 to 30 feet deep.
Dozens of avalanches released in the vicinity of Lookout Mountain, many of them above Bayhorse Rd. One outbuilding was struck and one play structure grazed.
Warm Springs Road closed due to an avalanche.
At least 8 avalanches reported on West Warm Springs Road blocking the road at multiple locations. One near Sandy Ln closing it to all traffic at end of pavement, and stayed closed through the 12th.
Avalanche along Lake Creek Rd off of Idaho 75 north of Ketchum with people trapped in a vehicle.
All lanes of Idaho 75 closed due to avalanche between Lake Creek Rd and Huelen Meadows.
Avalanche reported on Indian Creek Road near Sioux Dr.
Avalanche on Broadford Rd near Marina Dr just southwest of Friedman Memorial Airport.
Idaho Highway 75 blocked by avalanche near Glaassford Dr.
One residence and shed heavily damaged by avalanche in Georgetown Canyon 3 miles northeast of Georgetown.
Avalanche near intersection of Whipsaw Ln and W Warm Springs Rd.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Idaho in 2023Every state in 2023This day in weather historyWarnings in Idaho, 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: 1090851, 1090846, 1090896, 1090905, 1090925, 1090870, 1090887, 1090894, 1090920, 1090913, 1090915, 1090922, 1090924, 1090882, 1090884, 1090903, 1090892, 1090900, 1090853, 1090926, 1090927, 1090928, 1090929, 1090932, 1090933, 1090934, 1090930, 1090931, 1090935, 1090859, 1090936.