Catalina — Water Temperature in September

Water Temperature Range

7°C

minimum

13°C

average

18°C

maximum

Get instant access to real-time water temperatures for this and all other locations with our iOS and Android apps.

Water Temperature Chart for Month

The chart shows the average daily water temperature for each day of the month based on historical data.

Table of Water Temperatures by Day of the Month for Previous Years

Day	2026	2025	2024	2023
SEP 1	-10°C	17°C	13°C	14°C
SEP 2	17°C	14°C	13°C	14°C
SEP 3	16°C	14°C	13°C	14°C
SEP 4	16°C	13°C	13°C	13°C
SEP 5	16°C	13°C	13°C	13°C
SEP 6	16°C	13°C	13°C	13°C
SEP 7	16°C	14°C	13°C	14°C
SEP 8	15°C	14°C	14°C	14°C
SEP 9	15°C	14°C	14°C	14°C
SEP 10	14°C	13°C	13°C	13°C
SEP 11	14°C	14°C	13°C	14°C
SEP 12	13°C	14°C	14°C	13°C
SEP 13	14°C	14°C	14°C	13°C
SEP 14	14°C	13°C	13°C	13°C
SEP 15	14°C	13°C	13°C	13°C
SEP 16	14°C	13°C	13°C	12°C
SEP 17	13°C	13°C	13°C	13°C
SEP 18	13°C	13°C	13°C	13°C
SEP 19	13°C	13°C	12°C	13°C
SEP 20	13°C	13°C	13°C	13°C
SEP 21	13°C	13°C	13°C	13°C
SEP 22	12°C	13°C	12°C	13°C
SEP 23	12°C	13°C	13°C	13°C
SEP 24	12°C	13°C	13°C	13°C
SEP 25	11°C	13°C	13°C	13°C
SEP 26	11°C	12°C	12°C	12°C
SEP 27	11°C	12°C	12°C	12°C
SEP 28	11°C	12°C	12°C	12°C
SEP 29	11°C	12°C	12°C	12°C
SEP 30	11°C	12°C	12°C	13°C

September: Climate and Swimming Opportunities

Average Night Air Temperature

9°C

Average Day Air Temperature

16°C

Precipitation Amount per Month

78 mm

Number of Rainy Days

Daylight per Day

13 hrs

Sunshine per Day

4 hrs

Average Wind Speed

18 km/h

Average Humidity

88%

With such a ratio between the average monthly temperatures of water and air, swimming feels very cold and is only for cold-water enthusiasts. Most people will prefer just a brief splash, because warming up afterward can take time.