| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 20.3° | 10.7° | — | — | 94 |
| February | 20° | 9.8° | — | — | 94 |
| March | 21.3° | 10° | — | — | 94 |
| April | 22.9° | 10.7° | — | — | 94 |
| May | 24.9° | 12.1° | — | — | 94 |
| June | 27.7° | 13.9° | — | — | 91 |
| July | 31.2° | 16° | — | — | 77 |
| August | 31.8° | 16.7° | — | — | 75 |
| September | 30.8° | 16.7° | — | — | 79 |
| October | 27.4° | 15.1° | — | — | 92 |
| November | 23.6° | 12.6° | — | — | 94 |
| December | 19.7° | 10.3° | — | — | 93 |
January in Hacienda Heights averages a daily high of 20.3°C with nights around 10.7°C. Comfortable conditions for being outdoors all day.
February in Hacienda Heights averages a daily high of 20°C with nights around 9.8°C. Comfortable conditions for being outdoors all day.
March in Hacienda Heights averages a daily high of 21.3°C with nights around 10°C. Comfortable conditions for being outdoors all day.
April in Hacienda Heights averages a daily high of 22.9°C with nights around 10.7°C. Comfortable conditions for being outdoors all day.
May in Hacienda Heights averages a daily high of 24.9°C with nights around 12.1°C. Comfortable conditions for being outdoors all day.
June in Hacienda Heights averages a daily high of 27.7°C with nights around 13.9°C. Comfortable conditions for being outdoors all day.
July in Hacienda Heights averages a daily high of 31.2°C with nights around 16°C. Comfortable conditions for being outdoors all day.
August in Hacienda Heights averages a daily high of 31.8°C with nights around 16.7°C. Comfortable conditions for being outdoors all day.
September in Hacienda Heights averages a daily high of 30.8°C with nights around 16.7°C. Comfortable conditions for being outdoors all day.
October in Hacienda Heights averages a daily high of 27.4°C with nights around 15.1°C. Comfortable conditions for being outdoors all day.
November in Hacienda Heights averages a daily high of 23.6°C with nights around 12.6°C. Comfortable conditions for being outdoors all day.
December in Hacienda Heights averages a daily high of 19.7°C with nights around 10.3°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. Hacienda Heights peaks at 94.
Based on 30 years of records, October–June scores highest for comfort in Hacienda Heights, balancing daytime temperature against rainfall.
August is the warmest, averaging a daily high of 31.8°C.
January is the wettest, averaging —mm of rain across roughly — wet days.
December is the coolest month, with average daily highs around 19.7°C.