Knox County, Maine Tropical Cyclone History
Since 1861, 14 tropical cyclones have passed within 50 miles of Knox County, Maine — about one every 11.8 years. Of those, 2 were at hurricane strength at their closest approach. The most recent was Bertha (1996), which passed 4 miles away on 14 July 1996.
Storm tracks within 50 miles
How strong they get
Key facts
- Most recentBertha (1996) — 4 mi away, 14 July 1996
- Strongest stormUnnamed Storm (1869) — 80 kt (92 mph) at its strongest within 50 miles
- Closest pass on recordBertha (1996) — 4.4 miles
- Closest major hurricane (Cat 3+)None on record
- Passes within 25 miles7 of 14
- Peak monthSeptember — 7 storms (50% of all)
- Most active year1861 — 2 storms
- Most active decade1860s — 3 storms
- Major hurricanes (Cat 3+) within 50 mi0
- Record span1861–1996
When storms arrive
| J | F | M | A | M | J | J | A | S | O | N | D |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 0 | 0 | 0 | 0 | 0 | 0 | 3 | 2 | 7 | 1 | 1 | 0 |
Activity by decade
| 1860s | 1870s | 1880s | 1890s | 1900s | 1910s | 1920s | 1930s | 1940s | 1950s | 1960s | 1970s | 1980s | 1990s |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 3 | 0 | 1 | 1 | 0 | 1 | 0 | 0 | 1 | 2 | 1 | 2 | 0 | 2 |
Every tropical or subtropical cyclone within 50 miles
| Storm | Closest approach | Distance | Status | Wind |
|---|---|---|---|---|
| Bertha (1996) | 14 Jul 1996 | 4.4 mi | TS / TD | 55 kt |
| Bob (1991) | 20 Aug 1991 | 5.0 mi | TS / TD | 60 kt |
| Alfa (1973) | 1 Aug 1973 | 48.5 mi | TS / TD | 25 kt |
| Heidi (1971) | 14 Sep 1971 | 14.6 mi | TS / TD | 38 kt |
| Esther (1961) | 26 Sep 1961 | 37.9 mi | TS / TD | 35 kt |
| Cindy (1959) | 11 Jul 1959 | 43.4 mi | TS / TD | 46 kt |
| Able (1952) | 2 Sep 1952 | 32.4 mi | TS / TD | 25 kt |
| Unnamed Storm (1944) | 15 Sep 1944 | 15.6 mi | TS / TD | 57 kt |
| Unnamed Storm (1916) | 21 Jul 1916 | 6.5 mi | TS / TD | 42 kt |
| Unnamed Storm (1897) | 24 Sep 1897 | 15.6 mi | TS / TD | 33 kt |
| Unnamed Storm (1888) | 26 Sep 1888 | 42.8 mi | TS / TD | 55 kt |
| Unnamed Storm (1869) | 5 Oct 1869 | 43.7 mi | Cat 1 | 77 kt |
| Unnamed Storm (1861) | 3 Nov 1861 | 47.9 mi | TS / TD | 50 kt |
| Unnamed Storm (1861) | 28 Sep 1861 | 8.5 mi | TS / TD | 50 kt |
Post-tropical and extratropical passes
A further 19 systems passed within 50 miles after losing tropical characteristics. These are excluded from the counts above because they were no longer tropical cyclones at their closest approach — but several were highly damaging, so they are listed here. Showing the 8 most recent.
| Storm | Status | Closest approach | Distance | Wind |
|---|---|---|---|---|
| Elsa (2021) | Post-tropical | 9 Jul 2021 | 29.6 mi | 41 kt |
| Andrea (2013) | Post-tropical | 8 Jun 2013 | 44.3 mi | 40 kt |
| Hanna (2008) | Post-tropical | 7 Sep 2008 | 44.0 mi | 45 kt |
| Barry (2007) | Post-tropical | 5 Jun 2007 | 36.1 mi | 31 kt |
| Cindy (2005) | Post-tropical | 9 Jul 2005 | 31.6 mi | 30 kt |
| Floyd (1999) | Post-tropical | 17 Sep 1999 | 7.2 mi | 45 kt |
| Chris (1988) | Post-tropical | 30 Aug 1988 | 20.3 mi | 21 kt |
| Edna (1954) | Post-tropical | 12 Sep 1954 | 49.6 mi | 70 kt |
How Knox County, Maine compares
Among the 2,208 U.S. counties and county-equivalents that have recorded at least one tropical cyclone within 50 miles, Knox County, Maine ranks #1,040 — more exposed than 52.9% of them. Within Maine it ranks #6 of 16, against a state average of 12.1 storms per county.
Notable storms
- Cat 1 Unnamed Storm (1869) passed 44 miles away on 5 October 1869 as a hurricane, reaching 80 kt (92 mph) while within 50 miles.
- TS / TD Bob (1991) passed 5 miles away on 20 August 1991 as a tropical storm, reaching 60 kt (69 mph) while within 50 miles.
- TS / TD Unnamed Storm (1944) passed 16 miles away on 15 September 1944 as a hurricane, reaching 58 kt (67 mph) while within 50 miles.
- TS / TD Unnamed Storm (1888) passed 43 miles away on 26 September 1888 as a tropical storm, reaching 56 kt (64 mph) while within 50 miles.
12 of the 14 storms made a documented landfall somewhere along their track.
How often to expect a storm
A return interval of 11.8 years does not mean storms arrive on a schedule. It is simply 14 storms spread over the 165 years from 1861 to 2025. 1 separate year saw more than one storm pass within 50 miles while decades have gone by with none. The longest recorded quiet stretch was 28 years, between 1916 and 1944. It has been 29 years since the last one; 0 of the 12 gaps in this record were longer than that.
Common questions
How many hurricanes have hit Knox County, Maine?
2 tropical cyclones have passed within 50 miles of Knox County, Maine at hurricane strength since 1861. Counting all tropical cyclones — including tropical storms and depressions — the total is 14.
When was the last hurricane in Knox County, Maine?
Unnamed Storm (1944), on 15 September 1944, passing 16 miles away — 82 years ago. The most recent tropical cyclone of any strength was Bertha (1996) in 1996.
What was the strongest storm to affect Knox County, Maine?
Unnamed Storm (1869), which reached 80 kt (92 mph) while within 50 miles; its closest approach was 44 miles.
How often do hurricanes hit Knox County, Maine?
On average, one tropical cyclone passes within 50 miles every 11.8 years — 14 storms over the 165 years from 1861 to 2025, the end of the HURDAT2 record. That is a historical average, not a schedule or a forecast.
Nearby counties
Knox County, Maine borders or sits close to 5 other counties with a published storm record. Kennebec County, Maine has 16 on record.