| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 15.8° | 7.4° | 106mm | 10.6 | 65 |
| February | 16.9° | 8.2° | 97.9mm | 9.1 | 72 |
| March | 17.9° | 9.1° | 80.9mm | 10.4 | 72 |
| April | 18.9° | 10.1° | 33.5mm | 5.7 | 85 |
| May | 20.3° | 11.7° | 19mm | 3.3 | 93 |
| June | 22° | 13° | 4.8mm | 0.9 | 98 |
| July | 21.9° | 13.7° | 0.1mm | 0.1 | 100 |
| August | 22.9° | 14.4° | 1.4mm | 0.3 | 99 |
| September | 23.9° | 14.3° | 3mm | 0.9 | 98 |
| October | 22.7° | 12.7° | 31.3mm | 3 | 94 |
| November | 18.8° | 9.7° | 59.2mm | 6.7 | 83 |
| December | 15.4° | 7.6° | 129.7mm | 10.7 | 64 |
January in Alameda averages a daily high of 15.8°C with nights around 7.4°C. Expect roughly 10.6 wet days totalling 106mm. Generally workable, with some weather to plan around.
February in Alameda averages a daily high of 16.9°C with nights around 8.2°C. Expect roughly 9.1 wet days totalling 97.9mm. Generally workable, with some weather to plan around.
March in Alameda averages a daily high of 17.9°C with nights around 9.1°C. Expect roughly 10.4 wet days totalling 80.9mm. Generally workable, with some weather to plan around.
April in Alameda averages a daily high of 18.9°C with nights around 10.1°C. Expect roughly 5.7 wet days totalling 33.5mm. Comfortable conditions for being outdoors all day.
May in Alameda averages a daily high of 20.3°C with nights around 11.7°C. Expect roughly 3.3 wet days totalling 19mm. Comfortable conditions for being outdoors all day.
June in Alameda averages a daily high of 22°C with nights around 13°C. Rain is rare — about 0.9 wet days and 4.8mm across the month. Comfortable conditions for being outdoors all day.
July in Alameda averages a daily high of 21.9°C with nights around 13.7°C. Rain is rare — about 0.1 wet days and 0.1mm across the month. Comfortable conditions for being outdoors all day.
August in Alameda averages a daily high of 22.9°C with nights around 14.4°C. Rain is rare — about 0.3 wet days and 1.4mm across the month. Comfortable conditions for being outdoors all day.
September in Alameda averages a daily high of 23.9°C with nights around 14.3°C. Rain is rare — about 0.9 wet days and 3mm across the month. Comfortable conditions for being outdoors all day.
October in Alameda averages a daily high of 22.7°C with nights around 12.7°C. Expect roughly 3 wet days totalling 31.3mm. Comfortable conditions for being outdoors all day.
November in Alameda averages a daily high of 18.8°C with nights around 9.7°C. Expect roughly 6.7 wet days totalling 59.2mm. Comfortable conditions for being outdoors all day.
December in Alameda averages a daily high of 15.4°C with nights around 7.6°C. Expect roughly 10.7 wet days totalling 129.7mm. Generally workable, with some weather to plan around.
Each month scores out of 100. It starts at 100 and loses points for daytime highs outside a 20–27°C band, for wet days, and for nights below 2°C. Nothing else is weighted in — no crowd data, no prices, no opinion. Alameda peaks at 100.
Based on 30 years of records, May–October scores highest for comfort in Alameda, balancing daytime temperature against rainfall.
September is the warmest, averaging a daily high of 23.9°C.
December is the wettest, averaging 129.7mm of rain across roughly 10.7 wet days.
December is the coolest month, with average daily highs around 15.4°C.