Boston and London have similar daytime temperatures, London has 1.7°C (3.1°F) warmer nights, Boston gets 508 mm (20 in) more rain a year.
Boston is at its warmest in July and coolest in January, while London peaks in July and bottoms out in February. Month for month, Boston is the warmer of the two in 6 of 12 months.
Boston is the wetter of the two, collecting 1,213 mm (47.8 in) of rain a year against 705 mm (27.8 in) in London. The most comfortable time to visit is June, July and August in Boston and June, July and August in London.
| Boston | Metric | London |
|---|---|---|
| 🌡️ Temperature | ||
| 14.1°C | 🌡️Average daytime high | 14.3°C |
| 4.5°C | 🌙Average nighttime low | 6.2°C |
| July | 🔥Hottest month | July |
| January | ❄️Coldest month | February |
| 🌧️ Rain | ||
| 1,213 mm | 🌧️Annual rainfall | 705 mm |
| October | ☔Wettest month | October |
| February | 🏜️Driest month | April |
| 💨 Climate | ||
| 80% | 💧Average humidity | 85% |
| 0.7 m/s | 💨Average wind speed | 3.4 m/s |
Overnight, Boston typically falls to around 4.5°C (40.1°F) while London settles near 6.2°C (43.2°F).
Boston is hottest in July and coldest in January, whereas London peaks in July and is coolest in February.
Boston sees the most rain in October and the least in February; London is wettest in October and driest in April.
London feels the more humid of the two, averaging 85% relative humidity against 80%.
For London, the pick of the year is June, July and August.
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 | London | ||||
|---|---|---|---|---|---|---|
| Min | Avg | Max | Min | Avg | Max | |
| January | -7.9 | -3.9❄️ | 0.2 | 1.3 | 4❄️ | 6.7 |
| February | -7 | -2.7 | 1.6 | 1.2 | 4.4 | 7.5 |
| March | -3.1 | 1.5 | 6.1 | 2.5 | 6.5 | 10.4 |
| April | 2.1 | 7.3 | 12.5 | 4 | 8.7 | 13.3 |
| May | 8 | 13.3 | 18.6 | 7.1 | 11.9 | 16.7 |
| June | 13.3 | 18.4 | 23.5 | 10 | 14.9 | 19.9 |
| July | 16.9 | 22.1🔥 | 27.3 | 12.3 | 17.4🔥 | 22.4 |
| August | 16.3 | 21.7 | 27.1 | 12.3 | 17.3 | 22.4 |
| September | 12.3 | 17.8 | 23.2 | 10.1 | 14.8 | 19.5 |
| October | 6.5 | 11.4 | 16.4 | 7.5 | 11.3 | 15.1 |
| November | 1 | 5.3 | 9.6 | 4.3 | 7.2 | 10.2 |
| December | -4 | -0.3 | 3.4 | 2.4 | 4.9 | 7.3 |
| Annual Avg | 4.5 | 9.3 | 14.1 | 6.3 | 10.3 | 14.3 |
Min / mean / max temperature (°C). 🔥 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 London feel alike; where they separate, they are genuinely different places to be.
Hover or tap any point to read the exact figures. Boston London
See how Boston and London 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 London — each drawn straight from the climate figures above.
Boston and London are about equally warm. Daytime highs average 14.1°C (57.4°F) in Boston and 14.3°C (57.7°F) in London, so neither is clearly the warmer choice over the year. Nights are milder in London, with average lows of 6.2°C (43.2°F) versus 4.5°C (40.1°F).
Boston is hottest in July, averaging highs of about 27.3°C (81.1°F), while London peaks in July at around 22.4°C (72.4°F). That makes Boston 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 1.2°C (34.2°F) at the low point of the year in London.
Boston is the wetter city, collecting about 1,213 mm (47.8 in) of rain a year versus 705 mm (27.8 in) in London. Boston is wettest in October and driest in February; London is wettest in October and driest in April.
London is the more humid of the two, averaging 85% relative humidity over the year against 80% in Boston.
The most comfortable months in Boston are June, July and August, when average temperatures are at their mildest.
London is at its most pleasant around June, July and August, based on the mildest average temperatures of the year.
Boston is the warmer city in 6 of the 12 months of the year. The gap is widest in January, about 7.9°C (14.2°F), and narrowest in October, about 0.1°C (0.2°F).
Boston has the bigger seasonal swing, about 26°C (46.8°F) between its coldest and hottest months versus 13.4°C (24.1°F) in London — so London has the steadier, more even climate.
It depends what matters most to you: pick London if you prefer drier conditions and go for Boston 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 Boston and London, not a single year's weather or a short-range forecast.
