| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 21.3° | 9.2° | — | — | 94 |
| February | 21.4° | 8.9° | — | — | 94 |
| March | 23.4° | 9.7° | — | — | 94 |
| April | 25.4° | 10.8° | — | — | 94 |
| May | 26.9° | 12.7° | — | — | 94 |
| June | 30.2° | 14.7° | — | — | 81 |
| July | 34.2° | 16.8° | — | — | 65 |
| August | 35.2° | 16.8° | — | — | 61 |
| September | 33.4° | 16.1° | — | — | 68 |
| October | 29.2° | 14.1° | — | — | 85 |
| November | 25° | 11.2° | — | — | 94 |
| December | 20.6° | 8.8° | — | — | 94 |
January in West Covina averages a daily high of 21.3°C with nights around 9.2°C. Comfortable conditions for being outdoors all day.
February in West Covina averages a daily high of 21.4°C with nights around 8.9°C. Comfortable conditions for being outdoors all day.
March in West Covina averages a daily high of 23.4°C with nights around 9.7°C. Comfortable conditions for being outdoors all day.
April in West Covina averages a daily high of 25.4°C with nights around 10.8°C. Comfortable conditions for being outdoors all day.
May in West Covina averages a daily high of 26.9°C with nights around 12.7°C. Comfortable conditions for being outdoors all day.
June in West Covina averages a daily high of 30.2°C with nights around 14.7°C. Comfortable conditions for being outdoors all day.
July in West Covina averages a daily high of 34.2°C with nights around 16.8°C. Generally workable, with some weather to plan around.
August in West Covina averages a daily high of 35.2°C with nights around 16.8°C. Generally workable, with some weather to plan around.
September in West Covina averages a daily high of 33.4°C with nights around 16.1°C. Generally workable, with some weather to plan around.
October in West Covina averages a daily high of 29.2°C with nights around 14.1°C. Comfortable conditions for being outdoors all day.
November in West Covina averages a daily high of 25°C with nights around 11.2°C. Comfortable conditions for being outdoors all day.
December in West Covina averages a daily high of 20.6°C with nights around 8.8°C. Comfortable conditions for being outdoors all day.
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. West Covina peaks at 94.
Based on 30 years of records, November–May scores highest for comfort in West Covina, balancing daytime temperature against rainfall.
August is the warmest, averaging a daily high of 35.2°C.
January is the wettest, averaging —mm of rain across roughly — wet days.
December is the coolest month, with average daily highs around 20.6°C.