PowerOutageHistory
Reliability Grade
F
Least reliable
2018-2025
California

Tehama CountyPower Outage History

20182025 · California
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What this grade means

Bottom 20% least reliable nationally — frequent and/or long outages. This county ranks in the least reliable fifth of all US counties in our dataset: some combination of frequent outages, long restoration times, or customers affected puts it near the bottom nationally. Backup power is worth prioritizing here rather than treating it as optional.

Takeaway
High outage risk
Reliability Rank
Fuller bar = more reliable
Nationwide7th pct
In California#42 of 57
See full California rankings →
Total events
831
Recorded 2018–2025
Avg duration
4.7 hrs
Per outage event
Longest outage
194 hrs
Single worst event on record
Customers served
28,134
Utility customers in county

Outages by year

Outages by month (seasonality)

Worst outage events on record

DateDurationCustomers affectedCause
Oct 9, 20194 hrs22,542 (80%)Strong Wind
Oct 9, 2019<1 hr22,522 (80%)Strong Wind
Oct 10, 2019<1 hr22,507 (80%)Strong Wind
Oct 10, 20196 hrs22,507 (80%)Strong Wind
Oct 9, 20192 hrs22,507 (80%)Strong Wind

Was There an Outage on a Specific Date?

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

Over the 8 years from 2018 to 2025, Tehama County recorded 831 distinct power outage events, averaging 4.7 hours per event.

The single worst outage on record in Tehama County started October 9, 2019 (Strong Wind), lasting 4 hours and leaving up to 22,542 customers without power (80% of the county) at its peak.

October has historically been the worst month for outages in Tehama County, with 139 events recorded during that month across the dataset.

Based on this history, Tehama County earns a Reliability Grade of F, placing it in the 7th percentile nationally for grid reliability (higher percentile = more reliable).

Similar counties in California

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

CountyGradeNational percentile
Napa CountyF7th
Santa Cruz CountyF6th
Del Norte CountyF6th
Shasta CountyF9th
Humboldt CountyF5th

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 Tehama County?

Between 2018 and 2025, Tehama County recorded 831 outage events, averaging 4.7 hours each.

What is Tehama County's reliability grade?

Tehama County has a Reliability Grade of F, in the 7th national percentile.

What was the worst power outage in Tehama County?

The worst outage on record started October 9, 2019 (Strong Wind), lasting 4 hours and affecting up to 22,542 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.