PowerOutageHistory
Reliability Grade
A
Top tier
2019-2025
Tennessee

Hamilton CountyPower Outage History

20192025 · Tennessee
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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
Nationwide88th pct
In Tennessee#23 of 83
See full Tennessee rankings →
Total events
981
Recorded 2019–2025
Avg duration
1.9 hrs
Per outage event
Longest outage
63 hrs
Single worst event on record
Customers served
192,776
Utility customers in county

Outages by year

Outages by month (seasonality)

Worst outage events on record

DateDurationCustomers affectedCause
Jun 13, 20251 hrs114,753 (60%)Thunderstorm Wind
May 21, 2024<1 hr62,351 (32%)Unnamed event
Jul 8, 2024<1 hr37,858 (20%)Unnamed event
Nov 13, 2023<1 hr35,366 (18%)Unnamed event
Jun 13, 20251 hrs26,004 (13%)Thunderstorm Wind

Was There an Outage on a Specific Date?

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

Over the 7 years from 2019 to 2025, Hamilton County recorded 981 distinct power outage events, averaging 1.9 hours per event.

The single worst outage on record in Hamilton County started June 13, 2025 (Thunderstorm Wind), lasting 1 hours and leaving up to 114,753 customers without power (60% of the county) at its peak.

July has historically been the worst month for outages in Hamilton County, with 136 events recorded during that month across the dataset.

Based on this history, Hamilton County earns a Reliability Grade of A, placing it in the 88th percentile nationally for grid reliability (higher percentile = more reliable).

Similar counties in Tennessee

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

CountyGradeNational percentile
Overton CountyA88th
Gibson CountyA88th
Hamblen CountyA90th
Williamson CountyA90th
Anderson CountyA91st

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 Hamilton County?

Between 2019 and 2025, Hamilton County recorded 981 outage events, averaging 1.9 hours each.

What is Hamilton County's reliability grade?

Hamilton County has a Reliability Grade of A, in the 88th national percentile.

What was the worst power outage in Hamilton County?

The worst outage on record started June 13, 2025 (Thunderstorm Wind), lasting 1 hours and affecting up to 114,753 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.