Big Coppitt Key weather by month
What a typical year looks like in Big Coppitt Key, Florida: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at Key West International Airport, 11 km from Big Coppitt Key; records cover 1872–2026.
The year at a glance
- Precipitation a year
- 40.4 in1027 mm
- Snow a year
- Rare
- Last spring freeze
- Rare
- First fall freeze
- Rare
- Heating degree days
- 46
- Cooling degree days
- 5,120
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are 53°12° (heating, 99%) and 93°34° (cooling, 1%).
Month by month
Big Coppitt Key in January
Highs average 76°24° and lows 66°19°, with 1.8 in46 mm of precipitation in a typical January.
- Record high
- 90°32° (1877)
- Record low
- 41°5° (1886)
- Heating degree days
- 22
- Cooling degree days
- 197
Big Coppitt Key in February
Highs average 77°25° and lows 67°19°, with 1.5 in39 mm of precipitation in a typical February.
- Record high
- 87°31° (1874)
- Record low
- 44°7° (1899)
- Heating degree days
- 10
- Cooling degree days
- 214
Big Coppitt Key in March
Highs average 80°26° and lows 69°21°, with 1.5 in39 mm of precipitation in a typical March.
- Record high
- 89°32° (1873)
- Record low
- 47°8° (1986)
- Heating degree days
- 4
- Cooling degree days
- 297
Big Coppitt Key in April
Highs average 83°28° and lows 73°23°, with 2.1 in53 mm of precipitation in a typical April.
- Record high
- 91°33° (1881)
- Record low
- 48°9° (1987)
- Heating degree days
- 0
- Cooling degree days
- 386
Big Coppitt Key in May
Highs average 86°30° and lows 76°25°, with 3.1 in79 mm of precipitation in a typical May.
- Record high
- 94°34° (2019)
- Record low
- 63°17° (1877)
- Heating degree days
- 0
- Cooling degree days
- 501
Big Coppitt Key in June
Highs average 89°32° and lows 79°26°, with 4.2 in107 mm of precipitation in a typical June.
- Record high
- 96°36° (1881)
- Record low
- 65°18° (1932)
- Heating degree days
- 0
- Cooling degree days
- 572
Big Coppitt Key in July
Highs average 90°32° and lows 81°27°, with 3.6 in92 mm of precipitation in a typical July.
- Record high
- 97°36° (1880)
- Record low
- 68°20° (1888)
- Heating degree days
- 0
- Cooling degree days
- 632
Big Coppitt Key in August
Highs average 91°33° and lows 81°27°, with 5.4 in136 mm of precipitation in a typical August.
- Record high
- 97°36° (1956)
- Record low
- 68°20° (1894)
- Heating degree days
- 0
- Cooling degree days
- 637
Big Coppitt Key in September
Highs average 89°32° and lows 79°26°, with 7.2 in184 mm of precipitation in a typical September.
- Record high
- 95°35° (1872)
- Record low
- 69°21° (1892)
- Heating degree days
- 0
- Cooling degree days
- 573
Big Coppitt Key in OctoberThis month
Highs average 86°30° and lows 77°25°, with 5.7 in144 mm of precipitation in a typical October.
- Record high
- 93°34° (1962)
- Record low
- 59°15° (1892)
- Heating degree days
- 0
- Cooling degree days
- 505
Big Coppitt Key in November
Highs average 81°27° and lows 72°22°, with 2.1 in52 mm of precipitation in a typical November.
- Record high
- 91°33° (1876)
- Record low
- 49°9° (1959)
- Heating degree days
- 0
- Cooling degree days
- 348
Big Coppitt Key in December
Highs average 78°25° and lows 68°20°, with 2.2 in55 mm of precipitation in a typical December.
- Record high
- 88°31° (1876)
- Record low
- 44°7° (1876)
- Heating degree days
- 10
- Cooling degree days
- 258