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The temperatures in San Luis Obispo in September are comfortable with low of 16°C and and high up to 28°C.
There shouldn't be any rainy days in in San Luis Obispo during September. Having said that, the days are very hot in September so hanging out outside is more recomanded during the after noons and evening time.
Our weather forecast can give you a great sense of what weather to expect in San Luis Obispo in September 2025.
If you’re planning to visit San Luis Obispo in the near future, we highly recommend that you review the 14 day weather forecast for San Luis Obispo before you arrive.
Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
---|---|---|---|---|---|---|---|
January | 18° / 8° | 3 | 28 | 0 | 95 mm | Good | San Luis Obispo in January |
February | 18° / 7° | 4 | 25 | 0 | 74 mm | Good | San Luis Obispo in February |
March | 19° / 8° | 3 | 28 | 0 | 80 mm | Good | San Luis Obispo in March |
April | 21° / 9° | 2 | 28 | 0 | 24 mm | Good | San Luis Obispo in April |
May | 22° / 10° | 1 | 31 | 0 | 9 mm | Good | San Luis Obispo in May |
June | 25° / 13° | 0 | 30 | 0 | 2 mm | Perfect | San Luis Obispo in June |
July | 27° / 15° | 0 | 31 | 0 | 7 mm | Perfect | San Luis Obispo in July |
August | 27° / 16° | 0 | 31 | 0 | 1 mm | Perfect | San Luis Obispo in August |
September | 28° / 16° | 0 | 30 | 0 | 6 mm | Perfect | San Luis Obispo in September |
October | 24° / 14° | 1 | 30 | 0 | 22 mm | Perfect | San Luis Obispo in October |
November | 20° / 10° | 2 | 29 | 0 | 31 mm | Good | San Luis Obispo in November |
December | 16° / 7° | 3 | 28 | 0 | 65 mm | Good | San Luis Obispo in December |