Weather in San Diego County, United States in September

So you're interested in going to San Diego County, United States in September

September is a hot and very dry time for sunbathing in San Diego County. September is an excellent month for swimming in San Diego County with very warm sea temperatures. Consider visiting San Diego County in the months of June, July, August, September, for the best beach weather. Also consider one of our other suggestions for September.

Temperature in San Diego County in September

The average maximum temperature in San Diego County in September is 26°. The average maximum temperature is 26° in the previous month and 24° in the next month.

The average temperature in San Diego County in September is 21°. The average temperature ranges is 21° in the previous month and 18° in the next month.

The average minimum temperature in San Diego County in September is 17°. The minimum temperature is 18° in the previous month and 14° in the next month.

Sunshine in San Diego County in September

The average day light hours per day in San Diego County in September are 12.4 and there are 8.8 hours of sunshine per day on average during September making it a sunny month with few clouds.

The ultraviolet index in San Diego County in September is typically 9.2 during September. An ultraviolet index reading of 8 to 10 indicates a very high risk of harm from unprotected sun exposure. Unprotected skin risks burning in less than 15 minutes. Take extra precautions because unprotected skin and eyes will be damaged and can burn quickly. Tanning will be safest before 10am and after 4pm but only with a good application of sun screen. For those with sensitive skin stay in the shade and wear protective clothing, a wide-brimmed hat, and UV-blocking sunglasses. Generously apply broad spectrum SPF 30+ sunscreen every 2 hours, even on cloudy days. Watch out for relections from water that may increase ultraviolet exposure.

Sea Temperature in San Diego County in September

The average sea water temperature in San Diego County in September is 28.7° which is very warm and ideal for relaxing and swimming for the whole day.

Rainfall in San Diego County in September

The average total rainfall in San Diego County in September is 2.9cm and on average there are 2.2 rainy days in September making it a very dry time to visit the beach.

Humidity in San Diego County in September

The maximum dew point (an indicator of humidity) in San Diego County in September is 17° which is OK for most but slightly uncomfortable for some. The dew point is 17° in the previous month and 14° in the next month.

The average maximum relative humidity in San Diego County in September is typically 88.4%. The maximum relative humidity is 87.6% in the previous month and 86.5% in the next month.

The average relative humidity in San Diego County in September is typically 72.8%. The average relative humidity is 74% in the previous month and 68.5% in the next month.

Wind Speed in San Diego County in September

The average maximum wind speed in San Diego County in September is typically 18kmh. The average maximum wind speed is 18kmh in the previous month and 19kmh in the next month.

The average wind speed in San Diego County in September is typically 6kmh. The average wind speed is 6kmh in the previous month and 6kmh in the next month.

The average wind direction in San Diego County in September is from the West.

Monthly Averages

Suggested Beaches in September

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