The year at a glance
Averages from 30 years of climate history, 1991-2020
| Chicago | Metric | San Mateo |
|---|---|---|
| 180 days | Sunny daysclear or partly cloudy skies | 234 days |
| 39 in | Precipitationper year | 21 in |
| 132 days | Wet daysrain or snow per year | 56 days |
| 37 in | Snowfallper year | 0 in |
| 16 days | Hot daysabove 90 °F | 8 days |
| 102 days | Freezing nightsat or below 32 °F | 2 days |
| 71% | Humidityaverage relative | 77% |
| 52 °F | Average temperatureyear round | 59 °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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chicago high | 32 | 36 | 46 | 57 | 68 | 78 | 83 | 81 | 75 | 62 | 49 | 37 |
| San Mateo high | 58 | 61 | 64 | 66 | 69 | 73 | 74 | 75 | 76 | 73 | 64 | 58 |
| Chicago low | 20 | 23 | 31 | 41 | 51 | 61 | 67 | 67 | 60 | 47 | 36 | 25 |
| San Mateo low | 44 | 45 | 46 | 48 | 51 | 53 | 55 | 56 | 55 | 52 | 47 | 44 |
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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chicago | 2.4 | 2.1 | 2.8 | 4.5 | 4.4 | 4.0 | 3.6 | 3.8 | 3.0 | 3.3 | 2.8 | 2.4 |
| San Mateo | 3.9 | 4.2 | 3.2 | 1.6 | 0.8 | 0.2 | 0.0 | 0.0 | 0.1 | 0.9 | 2.0 | 3.7 |
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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chicago | 10 | 11 | 14 | 13 | 15 | 16 | 20 | 20 | 20 | 16 | 14 | 11 |
| San Mateo | 13 | 13 | 15 | 18 | 20 | 23 | 26 | 25 | 26 | 23 | 18 | 15 |
Keep comparing
Nearby cities and popular picks for each side of this matchup. Any two cities can be compared from the home page.
Chicago vs another city
- Chicago vs Cicero, IL
- Chicago vs Stickney, IL
- Chicago vs Berwyn, IL
- Chicago vs Oak Park, IL
- Chicago vs Riverside, IL
- Chicago vs Forest Park, IL
- Chicago vs New York, NY
- Chicago vs Los Angeles, CA
- Chicago vs Houston, TX
- Chicago vs Phoenix, AZ
- Chicago vs Philadelphia, PA
- Chicago vs San Antonio, TX
San Mateo vs another city
- San Mateo vs Hillsborough, CA
- San Mateo vs Foster City, CA
- San Mateo vs Belmont, CA
- San Mateo vs Burlingame, CA
- San Mateo vs San Carlos, CA
- San Mateo vs Millbrae, CA
- San Mateo vs New York, NY
- San Mateo vs Los Angeles, CA
- San Mateo vs Houston, TX
- San Mateo vs Phoenix, AZ
- San Mateo 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).