Johnson CountyPower Outage History
What this grade means
Better than average — fewer or shorter outages than most counties. This county's outage history is better than the national median: recorded outages are less frequent and/or shorter in duration than a typical US county experienced over the same 12-year period. It isn't in the top tier nationally, but its track record points to lower-than-average outage risk.
Outages by year
Outages by month (seasonality)
Worst outage events on record
| Date | Duration | Customers affected | Cause |
|---|---|---|---|
| Aug 12, 2022 | <1 hr | 3,889 (57%) | Unnamed event |
| Oct 23, 2018 | <1 hr | 3,638 (54%) | Unnamed event |
| May 31, 2018 | 4 hrs | 3,618 (53%) | Flood |
| Jan 6, 2018 | <1 hr | 3,617 (53%) | Unnamed event |
| Mar 23, 2018 | <1 hr | 3,611 (53%) | Unnamed event |
Was There an Outage on a Specific Date?
Pick a date to see whether a power outage was recorded for Johnson County, Wyoming that day.
Over the 9 years from 2017 to 2025, Johnson County recorded 532 distinct power outage events, averaging 2.2 hours per event.
The single worst outage on record in Johnson County started August 12, 2022, lasting less than 1 hour and leaving up to 3,889 customers without power (57% of the county) at its peak.
August has historically been the worst month for outages in Johnson County, with 82 events recorded during that month across the dataset.
Based on this history, Johnson County earns a Reliability Grade of B, placing it in the 69th percentile nationally for grid reliability (higher percentile = more reliable).
Similar counties in Wyoming
Counties with the closest reliability grade and national percentile to Johnson County.
| County | Grade | National percentile |
|---|---|---|
| Albany County | B | 71st |
| Sublette County | B | 64th |
| Hot Springs County | B | 73rd |
| Weston County | B | 64th |
| Carbon County | B | 75th |
Most reliable counties nationally
The top 3 counties nationally by reliability grade and percentile.
| County | State | Grade | National percentile |
|---|---|---|---|
| Clay County | South Dakota | A | 100th |
| Clearwater County | Minnesota | A | 99th |
| Limestone County | Alabama | A | 99th |
Least reliable counties nationally
The bottom 3 counties nationally by reliability grade and percentile.
| County | State | Grade | National percentile |
|---|---|---|---|
| Clay County | West Virginia | F | 0th |
| Lincoln County | West Virginia | F | 0th |
| Cameron Parish | Louisiana | F | 0th |
FAQ
How often does power go out in Johnson County?
Between 2017 and 2025, Johnson County recorded 532 outage events, averaging 2.2 hours each.
What is Johnson County's reliability grade?
Johnson County has a Reliability Grade of B, in the 69th national percentile.
What was the worst power outage in Johnson County?
The worst outage on record started August 12, 2022, lasting less than 1 hour and affecting up to 3,889 customers.