Measurements:
°C
°F
Key Largo
76°F
NW 13 mph
Feels like: 82°F
Precip: 0%
World Resorts USA Key Largo Weather

Key Largo Sea Water Temperature

Current Sea Water Temperature:
+77.0°F
Maximum Sea Water Temperature in December: 84.0°F
Minimum Sea Water Temperature in December: 71.6°F
Average water temperature in December: 78.2°F

Sea Water Temperature for the Last 10 Days:

December 18 77.0°F December 13 79.6°F
December 17 77.0°F December 12 81.2°F
December 16 78.4°F December 11 81.8°F
December 15 78.4°F December 10 82.8°F
December 14 79.2°F December 09 82.8°F

When is the Warmest Sea for Key Largo?

According to our data for the last three years for Key Largo the highest average sea water temperature was in August, July and September.

Average Water Temperature by Month, °F

Sea Water Temperature in August

Select Year: 2025 2024 2023

The average sea surface temperature in August 2025 for Key Largo was 93.0°F. The maximum and minimum values were 91.0°F and 94.6°F respectively.

Sea Water Temperature in July

Select Year: 2025 2024 2023

The average sea surface temperature in July 2025 for Key Largo was 90.3°F. The maximum and minimum values were 88.2°F and 93.6°F respectively.

Sea Water Temperature in September

Select Year: 2025 2024 2023

The average sea surface temperature in September 2025 for Key Largo was 90.6°F. The maximum and minimum values were 89.4°F and 92.8°F respectively.

Best Time to Visit Key Largo
The most sunny months:
March 11 days
April 11 days
January 10 days
The most warm months:
August 89.1 °F
July 89.0 °F
September 88.4 °F
Warmest sea temperature:
August 91.7 °F
July 91.2 °F
September 90.7 °F
The most cold months:
January 73.1 °F
December 75.0 °F
February 76.1 °F
The most rainy months:
June 3 days
September 3 days
July 3 days
The most windy months:
November 14 mph
March 14 mph
April 13 mph

Key Largo on the Weather Map

USA Resorts:
NAME
Chicago +42
Hawaii +80
Honolulu +80
Houston +74
Las Vegas +72
Los Angeles +84
Maui +76
Miami +80
Miami Beach +80
New York +48
San Diego +78
San Francisco +58
Sarasota +80
Tampa +82
Washington +52
24 Hours Weather Forecast
Key Largo
Local time: 17:31
18 dec, thursday
1800 76°F
NW
13 mph
2100 78°F
NW
13 mph
19 dec, friday
0000 78°F
NW
14 mph
0300 78°F
N
11 mph
0600 78°F
NE
9 mph
0900 78°F
NE
8 mph
1200 76°F
E
11 mph
1500 76°F
E
12 mph