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The weather in Fullerton in August is hot. The average temperatures are between 20°C and 30°C.
There shouldn't be any rainy days in in Fullerton during August. Having said that, the days are very hot in August 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 Fullerton in August 2025.
If you’re planning to visit Fullerton in the near future, we highly recommend that you review the 14 day weather forecast for Fullerton before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 20° / 10° | 3 | 28 | 0 | 63 mm | Good | Fullerton in January |
| February | 20° / 10° | 3 | 26 | 0 | 52 mm | Good | Fullerton in February |
| March | 21° / 11° | 3 | 28 | 0 | 47 mm | Good | Fullerton in March |
| April | 22° / 13° | 1 | 29 | 0 | 17 mm | Good | Fullerton in April |
| May | 23° / 14° | 1 | 30 | 0 | 7 mm | Perfect | Fullerton in May |
| June | 26° / 16° | 0 | 30 | 0 | 1 mm | Perfect | Fullerton in June |
| July | 29° / 19° | 1 | 31 | 0 | 2 mm | Good | Fullerton in July |
| August | 30° / 20° | 0 | 31 | 0 | 1 mm | Good | Fullerton in August |
| September | 30° / 20° | 0 | 30 | 0 | 4 mm | Good | Fullerton in September |
| October | 27° / 17° | 1 | 30 | 0 | 12 mm | Perfect | Fullerton in October |
| November | 23° / 13° | 2 | 28 | 0 | 19 mm | Perfect | Fullerton in November |
| December | 19° / 10° | 4 | 27 | 0 | 71 mm | Good | Fullerton in December |