The year at a glance
Averages from 30 years of climate history, 1991-2020
| Montclair | Metric | Ontario |
|---|---|---|
| 290 days | Sunny daysclear or partly cloudy skies | 284 days |
| 16 in | Precipitationper year | 11 in |
| 38 days | Wet daysrain or snow per year | 35 days |
| 0 in | Snowfallper year | 0 in |
| 80 days | Hot daysabove 90 °F | 93 days |
| 3 days | Freezing nightsat or below 32 °F | 3 days |
| 60% | Humidityaverage relative | 62% |
| 66 °F | Average temperatureyear round | 67 °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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Montclair high | 68 | 68 | 72 | 76 | 79 | 85 | 92 | 94 | 90 | 82 | 74 | 67 |
| Ontario high | 68 | 68 | 72 | 76 | 80 | 87 | 94 | 95 | 91 | 83 | 75 | 67 |
| Montclair low | 43 | 45 | 47 | 50 | 54 | 58 | 63 | 63 | 61 | 55 | 47 | 42 |
| Ontario low | 44 | 46 | 48 | 51 | 55 | 60 | 64 | 65 | 63 | 56 | 48 | 43 |
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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Montclair | 3.6 | 4.0 | 2.4 | 1.0 | 0.4 | 0.1 | 0.1 | 0.0 | 0.2 | 0.7 | 1.0 | 2.4 |
| Ontario | 2.4 | 2.8 | 1.7 | 0.8 | 0.4 | 0.1 | 0.1 | 0.0 | 0.1 | 0.6 | 0.8 | 1.7 |
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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Montclair | 19 | 17 | 20 | 23 | 25 | 28 | 29 | 30 | 29 | 27 | 24 | 21 |
| Ontario | 19 | 16 | 18 | 21 | 24 | 27 | 29 | 30 | 28 | 26 | 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.
Montclair vs another city
- Montclair vs Pomona, CA
- Montclair vs Upland, CA
- Montclair vs Claremont, CA
- Montclair vs La Verne, CA
- Montclair vs San Dimas, CA
- Montclair vs New York, NY
- Montclair vs Los Angeles, CA
- Montclair vs Chicago, IL
- Montclair vs Houston, TX
- Montclair vs Phoenix, AZ
- Montclair vs Philadelphia, PA
Ontario vs another city
- Ontario vs Chino, CA
- Ontario vs Eastvale, CA
- Ontario vs Upland, CA
- Ontario vs Rancho Cucamonga, CA
- Ontario vs Jurupa Valley, CA
- Ontario vs New York, NY
- Ontario vs Los Angeles, CA
- Ontario vs Chicago, IL
- Ontario vs Houston, TX
- Ontario vs Phoenix, AZ
- Ontario 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).