Washington is 3.8°C (6.8°F) warmer by day, Washington has 3.5°C (6.3°F) warmer nights, Boston gets 105 mm (4.1 in) more rain a year.
Boston is at its warmest in July 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.
Boston is the wetter of the two, collecting 1,213 mm (47.8 in) of rain a year against 1,108 mm (43.6 in) in Washington. The most comfortable time to visit is June, July and August in Boston and May, June and September in Washington.
| Boston | Metric | Washington |
|---|---|---|
| 🌡️ Temperature | ||
| 57.4°F | 🌡️Average daytime high | 64.2°F |
| 40.1°F | 🌙Average nighttime low | 46.4°F |
| July | 🔥Hottest month | July |
| January | ❄️Coldest month | January |
| 🌧️ Rain | ||
| 47.8 in | 🌧️Annual rainfall | 43.6 in |
| October | ☔Wettest month | July |
| February | 🏜️Driest month | February |
| 💨 Climate | ||
| 80% | 💧Average humidity | 76% |
| 0.7 m/s | 💨Average wind speed | 2.7 m/s |
Overnight, Boston typically falls to around 4.5°C (40.1°F) while Washington settles near 8°C (46.4°F).
Boston is hottest in July and coldest in January, whereas Washington peaks in July and is coolest in January.
Boston sees the most rain in October and the least in February; Washington is wettest in July and driest in February.
Boston feels the more humid of the two, averaging 80% 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 | Boston | Washington | ||||
|---|---|---|---|---|---|---|
| Min | Avg | Max | Min | Avg | Max | |
| January | 17.8 | 25❄️ | 32.4 | 24.8 | 32❄️ | 39.2 |
| February | 19.4 | 27.1 | 34.9 | 26.8 | 34.9 | 43 |
| March | 26.4 | 34.7 | 43 | 33.3 | 42.6 | 52 |
| April | 35.8 | 45.1 | 54.5 | 42.8 | 52.9 | 63.1 |
| May | 46.4 | 55.9 | 65.5 | 53.2 | 62.8 | 72.1 |
| June | 55.9 | 65.1 | 74.3 | 63 | 72.3 | 81.5 |
| July | 62.4 | 71.8🔥 | 81.1 | 68.9 | 78.3🔥 | 87.4 |
| August | 61.3 | 71.1 | 80.8 | 67.5 | 76.8 | 86.2 |
| September | 54.1 | 64 | 73.8 | 60.4 | 70 | 79.5 |
| October | 43.7 | 52.5 | 61.5 | 48.2 | 57.9 | 67.6 |
| November | 33.8 | 41.5 | 49.3 | 37.6 | 46.4 | 55.2 |
| December | 24.8 | 31.5 | 38.1 | 29.5 | 36.7 | 44.1 |
| Annual Avg | 40.1 | 48.7 | 57.4 | 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 Boston and Washington feel alike; where they separate, they are genuinely different places to be.
Hover or tap any point to read the exact figures. Boston Washington
See how Boston 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 Boston 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 14.1°C (57.4°F) in Boston — roughly 3.8°C (6.8°F) warmer by day. Nights are milder in Washington, with average lows of 8°C (46.4°F) versus 4.5°C (40.1°F).
Boston is hottest in July, averaging highs of about 27.3°C (81.1°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.
Boston gets colder. In its coldest month (January) overnight lows average about -7.9°C (17.7°F), compared with -4°C (24.8°F) at the low point of the year in Washington.
Boston is the wetter city, collecting about 1,213 mm (47.8 in) of rain a year versus 1,108 mm (43.6 in) in Washington. Boston is wettest in October and driest in February; Washington is wettest in July and driest in February.
Boston is the more humid of the two, averaging 80% relative humidity over the year against 76% in Washington.
The most comfortable months in Boston are June, July and August, 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 March, about 4.4°C (7.9°F), and narrowest in November, about 2.7°C (4.9°F).
Both have a similar seasonal range — around 26°C (46.8°F) between the coldest and hottest months — so neither climate is noticeably more extreme than the other.
On climate alone, Washington comes out ahead — it offers warmer days, less rain and lower humidity than Boston. Boston is the better fit only if you'd actually prefer cooler weather, more rainfall and a more humid climate.
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 Boston and Washington, not a single year's weather or a short-range forecast.
