Measurements:
°C
°F
Kauai
76°F
N 2 mph
Feels like: 80°F
Precip: 0%
World Resorts USA Kauai Weather

Kauai Sea Water Temperature

Current Sea Water Temperature:
+80.0°F
Maximum Sea Water Temperature in January: 81.8°F
Minimum Sea Water Temperature in January: 76.2°F
Average water temperature in January: 79.5°F

Sea Water Temperature for the Last 10 Days:

January 08 80.0°F January 03 80.4°F
January 07 79.8°F January 02 80.2°F
January 06 79.8°F January 01 80.4°F
January 05 80.0°F December 31 80.4°F
January 04 80.2°F December 30 80.6°F

When is the Warmest Sea for Kauai?

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

Average Water Temperature by Month, °F

Sea Water Temperature in September

Select Year: 2025 2024 2023

The average sea surface temperature in September 2025 for Kauai was 85.0°F. The maximum and minimum values were 84.6°F and 85.4°F respectively.

Sea Water Temperature in October

Select Year: 2025 2024 2023

The average sea surface temperature in October 2025 for Kauai was 84.8°F. The maximum and minimum values were 83.8°F and 85.4°F respectively.

Sea Water Temperature in August

Select Year: 2025 2024 2023

The average sea surface temperature in August 2025 for Kauai was 82.3°F. The maximum and minimum values were 79.0°F and 84.8°F respectively.

Best Time to Visit Kauai
The most sunny months:
January 6 days
December 5 days
February 4 days
The most warm months:
September 83.7 °F
August 83.4 °F
July 82.5 °F
Warmest sea temperature:
September 83.9 °F
October 83.8 °F
August 82.9 °F
The most cold months:
February 76.6 °F
March 76.9 °F
January 77.5 °F
The most rainy months:
March 2 days
January 2 days
November 1 day
The most windy months:
July 11 mph
June 11 mph
May 11 mph

Kauai on the Weather Map

USA Resorts:
NAME
Chicago +54
Hawaii +78
Honolulu +78
Houston +78
Las Vegas +54
Los Angeles +58
Maui +72
Miami +86
Miami Beach +80
New York +52
San Diego +64
San Francisco +52
Sarasota +82
Tampa +88
Washington +60
24 Hours Weather Forecast
Kauai
Local time: 10:32
08 jan, thursday
1200 80°F
S
4 mph
1500 76°F
SW
3 mph
1800 76°F
N
1 mph
2100 74°F
NW
3 mph
09 jan, friday
0000 74°F
N
2 mph
0300 74°F
NE
2 mph
0600 72°F
S
1 mph
0900 74°F
SE
1 mph