massoutage

2021 Montana Power Outage Report

In 2021, the average Montana customer went without power for about 4.9 hours, the 20th worst of 51 states (US average 8.4 hours). Figures from DOE/ORNL EAGLE-I, including major storm days.

Avg hrs / customer
4.9
vs prior year
▼ 12%
vs 2020
Customer-hours out
3.0M
Peak customers out
34,247
across the state at once
EAGLE-I coverage
76%
of MT customers
Counties reporting
51

Montana year over year

Montana: average hours without power per customer by year2015: 2.3h; 2016: 1.8h; 2017: 2.7h; 2018: 1.9h, coverage 16%; 2019: 0.6h, coverage 75%; 2020: 5.6h, coverage 76%; 2021: 4.9h, coverage 76%; 2022: 3.5h, coverage 76%; 2023: 1.8h; 2024: 8.5h; 2025: 6.7h02.557.5100%50%100%2.3h20151.8h20162.7h20171.9h20180.6h20195.6h20204.9h20213.5h20221.8h20238.5h20246.7h2025
Use the arrow keys to read values.
Average hours without power per customer. Line: EAGLE-I coverage, share of customers tracked (right axis).

Month by month, 2021

Customer-hours without power across Montana; January was the worst.

CSVJSON
Montana customer-hours without power by month, 2021Jan 1.0M, Feb 118K, Mar 113K, Apr 132K, May 152K, Jun 281K, Jul 181K, Aug 149K, Sep 101K, Oct 132K, Nov 431K, Dec 148K0500k1M1.5M1.0MJan118KFeb113KMar132KApr152KMay281KJun181KJul149KAug101KSep132KOct431KNov148KDec
Use the arrow keys to read values.

All 51 Montana counties, 2021

Ranked by average hours without power per customer. Each county links to its annual report.

CSVJSON
#CountyHrs / customerCustomer-hoursCustomersPeak outEvents
1Meagher County55.428K513513107
2Mineral County47.1116K2,4552,45590
3Sanders County37.8277K7,3147,314239
4Lincoln County22.6287K12,7215,955207
5Teton County17.636K2,0501,936116
6Wheatland County16.311K70570572
7Valley County15.761K3,9123,21795
8Judith Basin County15.315K1,00671851
9Chouteau County12.224K1,9591,428128
10Phillips County12.124K1,9921,992100
11Granite County9.722K2,293910145
12Broadwater County9.313K1,4121,41298
13Madison County9.056K6,1992,860250
14Blaine County8.624K2,7402,641141
15Flathead County8.3541K65,57510,795575
16Carbon County8.153K6,5121,329175
17Sweet Grass County8.116K1,9931,31487
18Hill County7.962K7,8767,180169
19Richland County7.977K9,8052,96733
20Lewis and Clark County7.2236K32,88727,788514
21Liberty County7.15,73380480450
22Rosebud County5.827K4,6471,18270
23Pondera County5.812K2,0311,186108
24Park County5.448K8,7632,440169
25Cascade County5.0194K39,1666,002477
26Jefferson County4.826K5,3221,694205
27Deer Lodge County3.926K6,6631,679179
28Fergus County3.620K5,38437787
29Wibaux County2.81,9046753616
30Sheridan County2.74,8371,76699123
31Fallon County2.65,9732,2801,17940
32Beaverhead County2.48,8013,61285666
33Gallatin County2.2213K96,6039,419533
34Missoula County1.9112K57,3486,378471
35Stillwater County1.79,1605,3831,33860
36Yellowstone County1.6127K77,6062,153624
37Lake County1.639K24,04197982
38Ravalli County1.640K25,0432,458262
39Roosevelt County1.511K7,25277231
40Dawson County1.511K7,4352,57049
41Musselshell County1.53,5532,36210586
42Powell County1.56,7694,506656108
43Silver Bow County1.434K24,0745,468285
44Prairie County1.180075845111
45Powder River County1.05895833221
46Custer County0.64,3176,94267676
47Big Horn County0.53,1006,86510569
48Garfield County0.0481,61311
49Carter County0.0750812
50Daniels County-716-6435
51Golden Valley County-5,305-59147

Biggest Montana outages of 2021

Up to 25 county outage episodes with the most customers out at once.

CSVJSON
#CountyStarted (UTC)Ended (UTC)DurationPeak outCustomer-hours
1Lewis and Clark County, MTJune 3, 2021 23:45June 4, 2021 22:1522h 30m27,78872K
2Flathead County, MTJanuary 13, 2021 14:15January 19, 2021 00:005d 9h10,795304K
3Gallatin County, MTSeptember 15, 2021 13:30September 15, 2021 20:006h 30m9,41918K
4Sanders County, MTJanuary 13, 2021 13:15January 27, 2021 00:0013d 10h7,314232K
5Hill County, MTNovember 5, 2021 02:45November 5, 2021 13:1510h 30m7,18025K
6Flathead County, MTDecember 29, 2021 21:30December 30, 2021 00:152h 45m6,5999,634
7Flathead County, MTNovember 15, 2021 23:45November 19, 2021 00:153d6,546101K
8Missoula County, MTAugust 2, 2021 02:30August 2, 2021 07:004h 30m6,37821K
9Gallatin County, MTOctober 11, 2021 12:45October 12, 2021 02:4514h6,26228K
10Cascade County, MTApril 12, 2021 00:45April 12, 2021 06:155h 30m6,00217K
11Lincoln County, MTJune 9, 2021 18:45June 9, 2021 19:3045m5,9554,387
12Lincoln County, MTAugust 3, 2021 14:30August 3, 2021 14:4515m5,7981,450
13Lewis and Clark County, MTJuly 19, 2021 12:45July 19, 2021 15:002h 15m5,59311K
14Lewis and Clark County, MTApril 6, 2021 05:45April 6, 2021 13:307h 45m5,51614K
15Silver Bow County, MTJuly 20, 2021 15:45July 20, 2021 21:305h 45m5,46813K
16Gallatin County, MTJanuary 30, 2021 11:15January 31, 2021 06:4519h 30m5,45530K
17Gallatin County, MTFebruary 12, 2021 01:15February 12, 2021 08:006h 45m5,42015K
18Lewis and Clark County, MTAugust 26, 2021 17:15August 27, 2021 02:008h 45m4,5277,262
19Lincoln County, MTNovember 15, 2021 23:30November 19, 2021 21:453d 22h4,523105K
20Flathead County, MTJune 13, 2021 20:00June 14, 2021 00:154h 15m4,2807,001
21Lincoln County, MTJanuary 13, 2021 14:15January 17, 2021 07:153d 17h4,132144K
22Flathead County, MTFebruary 17, 2021 21:00February 18, 2021 00:453h 45m3,9334,337
23Cascade County, MTApril 4, 2021 09:00April 5, 2021 18:451d 9h3,81514K
24Missoula County, MTNovember 16, 2021 00:15November 17, 2021 02:001d 1h3,68426K
25Lewis and Clark County, MTJanuary 13, 2021 16:00January 17, 2021 07:153d 15h3,47040K
EAGLE-I tracked about 76% of Montana's electricity customers in 2021; outages at utilities it does not see are not counted. Hours per customer divide outage customer-minutes by modeled county customers.
Montana by year:2025202420232022202020192018201720162015
Other states in 2021:LAMIWVORTXMSKYNC

Part of the 2021 US Power Outage Report.

Data from DOE EAGLE-I, every source we read.