PowerOutageHistory
C

LaSalle County Power Outage History

20142025 · Illinois

Average — typical outage frequency and duration nationally. How grades are calculated

Total events
654
Avg duration
2.8 hrs
Longest outage
126 hrs
National percentile
49th

Outages by year

Outages by month (seasonality)

Worst outage events on record

DateDurationCustomers affectedCause
Aug 10, 2020126 hrs30,069 (46%)Thunderstorm Wind
Feb 28, 201760 hrs9,860 (15%)Tornado
Aug 11, 202119 hrs9,828 (15%)Thunderstorm Wind
Jun 14, 201727 hrs7,332 (11%)Thunderstorm Wind
Oct 25, 20241 hrs7,019 (11%)Drought

Over the 12 years from 2014 to 2025, LaSalle County recorded 654 distinct power outage events, averaging 2.8 hours per event.

The single worst outage on record in LaSalle County started August 10, 2020 (Thunderstorm Wind), lasting 126 hours and leaving up to 30,069 customers without power (46% of the county) at its peak.

June has historically been the worst month for outages in LaSalle County, with 86 events recorded during that month across the dataset.

Based on this history, LaSalle County earns a Reliability Grade of C, placing it in the 49th percentile nationally for grid reliability (higher percentile = more reliable).

Sized for LaSalle County's outage profile

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Outage-prep kit

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Similar counties in Illinois

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

CountyGradeNational percentile
Calhoun CountyC49th
Logan CountyC50th
Jo Daviess CountyC50th
Christian CountyC48th
Knox CountyC50th

FAQ

How often does power go out in LaSalle County?

Between 2014 and 2025, LaSalle County recorded 654 outage events, averaging 2.8 hours each.

What is LaSalle County's reliability grade?

LaSalle County has a Reliability Grade of C, in the 49th national percentile.

What was the worst power outage in LaSalle County?

The worst outage on record started August 10, 2020 (Thunderstorm Wind), lasting 126 hours and affecting up to 30,069 customers.

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.