PowerOutageHistory
Reliability Grade
A
Top tier
2017-2025
Wyoming

Sheridan CountyPower Outage History

20172025 · Wyoming
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What this grade means

Top 20% most reliable nationally — infrequent, short outages. This county ranks in the most reliable fifth of all US counties in our dataset, based on 12 years of real DOE outage records: outages happen less often here, and when they do occur they tend to be resolved quickly compared to the rest of the country. Baseline outage risk is low, though a severe local storm can still occasionally cause a longer-than-usual outage regardless of the long-term track record.

Takeaway
Low outage risk
Reliability Rank
Fuller bar = more reliable
Nationwide82nd pct
In Wyoming#12 of 22
See full Wyoming rankings →
Total events
254
Recorded 2017–2025
Avg duration
2.6 hrs
Per outage event
Longest outage
58 hrs
Single worst event on record
Customers served
18,591
Utility customers in county

Outages by year

Outages by month (seasonality)

Worst outage events on record

DateDurationCustomers affectedCause
Nov 13, 20257 hrs12,017 (65%)Unnamed event
Sep 11, 20223 hrs4,930 (27%)Unnamed event
Feb 16, 20237 hrs3,907 (21%)Winter Storm
Apr 23, 20225 hrs3,262 (18%)Winter Storm
Sep 26, 20231 hrs3,176 (17%)Unnamed event

Was There an Outage on a Specific Date?

Pick a date to see whether a power outage was recorded for Sheridan County, Wyoming that day.

Over the 9 years from 2017 to 2025, Sheridan County recorded 254 distinct power outage events, averaging 2.6 hours per event.

The single worst outage on record in Sheridan County started November 13, 2025, lasting 7 hours and leaving up to 12,017 customers without power (65% of the county) at its peak.

June has historically been the worst month for outages in Sheridan County, with 38 events recorded during that month across the dataset.

Based on this history, Sheridan County earns a Reliability Grade of A, placing it in the 82nd percentile nationally for grid reliability (higher percentile = more reliable).

Similar counties in Wyoming

Counties with the closest reliability grade and national percentile to Sheridan County.

CountyGradeNational percentile
Big Horn CountyA82nd
Sweetwater CountyA81st
Campbell CountyB80th
Natrona CountyA87th
Park CountyA88th

Most reliable counties nationally

The top 3 counties nationally by reliability grade and percentile.

CountyStateGradeNational percentile
Clay CountySouth DakotaA100th
Clearwater CountyMinnesotaA99th
Limestone CountyAlabamaA99th

Least reliable counties nationally

The bottom 3 counties nationally by reliability grade and percentile.

FAQ

How often does power go out in Sheridan County?

Between 2017 and 2025, Sheridan County recorded 254 outage events, averaging 2.6 hours each.

What is Sheridan County's reliability grade?

Sheridan County has a Reliability Grade of A, in the 82nd national percentile.

What was the worst power outage in Sheridan County?

The worst outage on record started November 13, 2025, lasting 7 hours and affecting up to 12,017 customers.

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Data: ORNL EAGLE-I Recorded Electricity Outages (2014–2025), CC BY 4.0. Storm names: NOAA Storm Events Database. Last data refresh: 2025. See methodology.