Washington is 5.7°C (10.3°F) warmer by day, Washington has 1.4°C (2.5°F) warmer nights, Washington gets 141 mm (5.6 in) more rain a year.
Chicago is at its warmest in August and coolest in January, while Washington peaks in July and bottoms out in January. Month for month, Washington is the warmer of the two in 12 of 12 months.
Washington is the wetter of the two, collecting 1,108 mm (43.6 in) of rain a year against 967 mm (38.1 in) in Chicago. The most comfortable time to visit is July, August and September in Chicago and May, June and September in Washington.
| Chicago | Metric | Washington |
|---|---|---|
| 🌡️ Temperature | ||
| 54°F | 🌡️Average daytime high | 64.2°F |
| 43.9°F | 🌙Average nighttime low | 46.4°F |
| August | 🔥Hottest month | July |
| January | ❄️Coldest month | January |
| 🌧️ Rain | ||
| 38.1 in | 🌧️Annual rainfall | 43.6 in |
| May | ☔Wettest month | July |
| January | 🏜️Driest month | February |
| 💨 Climate | ||
| 81% | 💧Average humidity | 76% |
| 4.4 m/s | 💨Average wind speed | 2.7 m/s |
Overnight, Chicago typically falls to around 6.6°C (43.9°F) while Washington settles near 8°C (46.4°F).
Chicago is hottest in August and coldest in January, whereas Washington peaks in July and is coolest in January.
Chicago sees the most rain in May and the least in January; Washington is wettest in July and driest in February.
Chicago feels the more humid of the two, averaging 81% relative humidity against 76%.
For Washington, the pick of the year is May, June and September.
Month by month, here is the coldest night, the average day and the hottest afternoon each city can expect. Switch Compare to read rainfall, humidity, wind or solar instead, and Period to move between the long-term 45-year average and any single year — the shading is a quick warm-to-cool guide.
| Month | Chicago | Washington | ||||
|---|---|---|---|---|---|---|
| Min | Avg | Max | Min | Avg | Max | |
| January | 22.1 | 26.6❄️ | 31.1 | 24.8 | 32❄️ | 39.2 |
| February | 23.7 | 28.4 | 33.1 | 26.8 | 34.9 | 43 |
| March | 30.9 | 36 | 41 | 33.3 | 42.6 | 52 |
| April | 38.5 | 44.1 | 49.6 | 42.8 | 52.9 | 63.1 |
| May | 47.1 | 52.9 | 58.6 | 53.2 | 62.8 | 72.1 |
| June | 57.9 | 63.5 | 69.1 | 63 | 72.3 | 81.5 |
| July | 66.2 | 71.1 | 75.9 | 68.9 | 78.3🔥 | 87.4 |
| August | 66.6 | 71.4🔥 | 76.1 | 67.5 | 76.8 | 86.2 |
| September | 60.1 | 65.3 | 70.5 | 60.4 | 70 | 79.5 |
| October | 48.7 | 54 | 59.2 | 48.2 | 57.9 | 67.6 |
| November | 37.4 | 42.1 | 46.6 | 37.6 | 46.4 | 55.2 |
| December | 27.7 | 31.6 | 35.8 | 29.5 | 36.7 | 44.1 |
| Annual Avg | 43.9 | 48.9 | 54 | 46.4 | 55.2 | 64.2 |
Min / mean / max temperature (°F). 🔥 marks each city's hottest month, ❄️ its coldest; shading runs cool blue to warm red.
The same figures plotted out, so the shape of a typical year is easier to see than in a grid. Where the two lines run close together Chicago and Washington feel alike; where they separate, they are genuinely different places to be.
Hover or tap any point to read the exact figures. Chicago Washington
See how Chicago and Washington stack up against other cities. Swipe for more.
Choose which city to keep, then search for any other city in our database — we'll build the comparison for you.
Quick answers to the questions people ask most when comparing Chicago and Washington — each drawn straight from the climate figures above.
Washington is the warmer of the two. It averages daytime highs of 17.9°C (64.2°F) against 12.2°C (54°F) in Chicago — roughly 5.7°C (10.3°F) warmer by day. Nights are milder in Washington, with average lows of 8°C (46.4°F) versus 6.6°C (43.9°F).
Chicago is hottest in August, averaging highs of about 24.5°C (76.1°F), while Washington peaks in July at around 30.8°C (87.5°F). That makes Washington the hotter of the two at the height of summer.
Chicago gets colder. In its coldest month (January) overnight lows average about -5.5°C (22.2°F), compared with -4°C (24.8°F) at the low point of the year in Washington.
Washington is the wetter city, collecting about 1,108 mm (43.6 in) of rain a year versus 967 mm (38.1 in) in Chicago. Chicago is wettest in May and driest in January; Washington is wettest in July and driest in February.
Chicago is the more humid of the two, averaging 81% relative humidity over the year against 76% in Washington.
The most comfortable months in Chicago are July, August and September, when average temperatures are at their mildest.
Washington is at its most pleasant around May, June and September, based on the mildest average temperatures of the year.
Washington is the warmer city in all 12 months of the year. The gap is widest in May, about 5.5°C (9.9°F), and narrowest in October, about 2.2°C (4°F).
Both have a similar seasonal range — around 25.7°C (46.3°F) between the coldest and hottest months — so neither climate is noticeably more extreme than the other.
It depends what matters most to you: choose Washington for warmer weather, pick Chicago if you prefer drier conditions and go for Washington if you want lower humidity. There is no single "better" climate — it comes down to whether you value warmth, dryness or comfort most.
Every figure on this page is calculated from NASA POWER satellite climate data spanning 1981–2025 (45 years). The averages describe the long-term climate of Chicago and Washington, not a single year's weather or a short-range forecast.
