Altadena and San Marino have remarkably similar climates.
The year at a glance
Averages from 30 years of climate history, 1991-2020
| Altadena | Metric | San Marino |
|---|---|---|
| 294 days | Sunny daysclear or partly cloudy skies | 291 days |
| 15 in | Precipitationper year | 14 in |
| 37 days | Wet daysrain or snow per year | 34 days |
| 0 in | Snowfallper year | 0 in |
| 71 days | Hot daysabove 90 °F | 68 days |
| 0 days | Freezing nightsat or below 32 °F | 0 days |
| 56% | Humidityaverage relative | 59% |
| 66 °F | Average temperatureyear round | 66 °F |
Monthly temperatures
Average daily high and low for each month, in °F. The gap between the two lines is what an ordinary day feels like across the year.
Daily highs
Daily lows
View monthly temperatures as a table
| City | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Altadena high | 68 | 69 | 72 | 76 | 78 | 83 | 88 | 91 | 89 | 83 | 75 | 67 |
| San Marino high | 68 | 69 | 72 | 75 | 77 | 82 | 87 | 89 | 88 | 82 | 74 | 67 |
| Altadena low | 45 | 46 | 49 | 51 | 55 | 58 | 62 | 64 | 62 | 56 | 49 | 45 |
| San Marino low | 46 | 47 | 49 | 52 | 56 | 60 | 64 | 64 | 63 | 57 | 50 | 45 |
Monthly precipitation
Total rain plus melted snow for each month, in inches. Taller bars mean wetter months.
View monthly precipitation as a table
| City | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Altadena | 3.4 | 3.7 | 2.5 | 1.0 | 0.5 | 0.1 | 0.1 | 0.0 | 0.2 | 0.7 | 0.9 | 2.3 |
| San Marino | 3.3 | 3.5 | 2.2 | 0.9 | 0.4 | 0.1 | 0.1 | 0.0 | 0.1 | 0.6 | 0.8 | 2.2 |
Monthly sunny days
Days each month with clear or partly cloudy skies, so compare the same month between cities.
View monthly sunny days as a table
| City | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Altadena | 20 | 17 | 21 | 23 | 25 | 28 | 29 | 30 | 29 | 27 | 24 | 22 |
| San Marino | 19 | 18 | 21 | 23 | 24 | 27 | 29 | 30 | 28 | 27 | 24 | 21 |
Keep comparing
Nearby cities and popular picks for each side of this matchup. Any two cities can be compared from the home page.
Altadena vs another city
- Altadena vs Pasadena, CA
- Altadena vs La Cañada Flintridge, CA
- Altadena vs East Pasadena, CA
- Altadena vs Sierra Madre, CA
- Altadena vs South Pasadena, CA
- Altadena vs New York, NY
- Altadena vs Los Angeles, CA
- Altadena vs Chicago, IL
- Altadena vs Houston, TX
- Altadena vs Phoenix, AZ
- Altadena vs Philadelphia, PA
San Marino vs another city
- San Marino vs East San Gabriel, CA
- San Marino vs San Gabriel, CA
- San Marino vs East Pasadena, CA
- San Marino vs South Pasadena, CA
- San Marino vs Pasadena, CA
- San Marino vs Alhambra, CA
- San Marino vs New York, NY
- San Marino vs Los Angeles, CA
- San Marino vs Chicago, IL
- San Marino vs Houston, TX
- San Marino vs Phoenix, AZ
- San Marino vs Philadelphia, PA
About this data
Every figure on this page is a 30 year average computed from daily climate history for 1991-2020, using each city's own coordinates. Wet days count days with measurable precipitation, calibrated against the wet day counts in NOAA's published climate normals. Sunny days count clear plus partly cloudy days, defined as average cloud cover of 63 percent or less and calibrated against NOAA's published sky cover tables. Snowfall figures are model estimates anchored to NOAA station measurements near each city.
Weather data by Open-Meteo.com (CC BY 4.0). Contains modified Copernicus Climate Change Service information (ERA5, ERA5-Land).