Boston Climate & Weather Averages
United States · Humid Continental climate · Data averaged from 2020-01-01 to 2024-12-31 (5 years)
Best Time to Visit Boston
Based on temperature comfort, low rainfall, and sunshine hours, the best months to visit Boston are:
July, August, June
Scores based on ideal temperature (18-28°C), low precipitation, and high sunshine. July scores 64/100.
Boston has a Humid Continental climate with warm summers and very cold winters. The warmest month is July with an average temperature of 23.8°C (74.8°F), while January is the coldest at -0.4°C (31.3°F). Annual precipitation averages 1219.0mm spread across approximately 161.0 rainy days per year, with December being the wettest month at 131.7mm and November the driest at 74.4mm. The city receives an average of 5.6-11.4 hours of sunshine per day, with the sunniest months being June and July. Humidity remains relatively consistent throughout the year, averaging around 71.0% annually, while average wind speeds reach 20.6 km/h. The overall annual mean temperature is 11.2°C (52.2°F), reflecting the humid continental conditions shaped by Boston's latitude (42.36°) and surrounding geography. For travelers, the best time to visit is July, August, June, when temperatures are comfortable and rainfall is lower.
Boston's four distinct seasons make it one of the most dynamic New England cities for climate study. I've tracked the data and found that the city experiences beautiful autumns, cold winters, mild springs, and warm summers. The best time for visiting is May to October, with September being the ideal month for comfortable temperatures and the famous fall foliage.
Seasonal Climate Overview
Spring (Mar-May)
Average temperature 9.2°C (48.6°F), rainfall 100.1mm, sunshine 9.1 hrs/day, humidity 67.3%. Mild transitional weather characterizes this period. Expect around 14.3 rainy days per month.
Summer (Jun-Aug)
Average temperature 22.3°C (72.1°F), rainfall 95.4mm, sunshine 11.1 hrs/day, humidity 72.1%. Warm season conditions prevail. Expect around 17.3 rainy days per month.
Autumn (Sep-Nov)
Average temperature 12.9°C (55.2°F), rainfall 105.7mm, sunshine 7.9 hrs/day, humidity 74.2%. Mild transitional weather characterizes this period. Expect around 11.8 rainy days per month.
Winter (Dec-Feb)
Average temperature 0.6°C (33.1°F), rainfall 105.2mm, sunshine 6.0 hrs/day, humidity 70.4%. Cold season conditions dominate. Expect around 10.1 rainy days per month.
Monthly Temperature Averages (°C / °F)
| Month | Avg High | Avg Low | Mean Temp |
|---|---|---|---|
| January | 3.6°C (38.5°F) | -4.2°C (24.4°F) | -0.4°C (31.3°F) |
| February | 4.9°C (40.8°F) | -4.9°C (23.2°F) | -0.0°C (32.0°F) |
| March | 9.3°C (48.7°F) | -0.6°C (30.9°F) | 4.3°C (39.7°F) |
| April | 13.2°C (55.8°F) | 3.9°C (39.0°F) | 8.4°C (47.1°F) |
| May | 20.1°C (68.2°F) | 9.7°C (49.5°F) | 14.8°C (58.6°F) |
| June | 25.8°C (78.4°F) | 15.4°C (59.7°F) | 20.4°C (68.7°F) |
| July | 28.7°C (83.7°F) | 19.4°C (66.9°F) | 23.8°C (74.8°F) |
| August | 27.6°C (81.7°F) | 18.4°C (65.1°F) | 22.7°C (72.9°F) |
| September | 23.0°C (73.4°F) | 14.5°C (58.1°F) | 18.5°C (65.3°F) |
| October | 17.7°C (63.9°F) | 9.1°C (48.4°F) | 13.1°C (55.6°F) |
| November | 11.6°C (52.9°F) | 2.8°C (37.0°F) | 7.1°C (44.8°F) |
| December | 6.2°C (43.2°F) | -1.7°C (28.9°F) | 2.2°C (36.0°F) |
Monthly Precipitation (mm)
| Month | Avg Rainfall | Bar |
|---|---|---|
| January | 109.0 mm | |
| February | 74.9 mm | |
| March | 114.7 mm | |
| April | 98.6 mm | |
| May | 86.9 mm | |
| June | 75.6 mm | |
| July | 118.5 mm | |
| August | 92.2 mm | |
| September | 126.5 mm | |
| October | 116.1 mm | |
| November | 74.4 mm | |
| December | 131.7 mm |
Monthly Rainy Days (avg days with rain > 0.1mm)
| Month | Avg Rainy Days | Bar |
|---|---|---|
| January | 9.6 | |
| February | 8.8 | |
| March | 14.0 | |
| April | 15.0 | |
| May | 14.0 | |
| June | 16.8 | |
| July | 18.2 | |
| August | 17.0 | |
| September | 14.8 | |
| October | 11.2 | |
| November | 9.4 | |
| December | 12.0 |
Monthly Humidity (%)
| Month | Avg Humidity | Bar |
|---|---|---|
| January | 69.3% | |
| February | 69.1% | |
| March | 66.8% | |
| April | 68.8% | |
| May | 66.2% | |
| June | 69.8% | |
| July | 73.0% | |
| August | 73.6% | |
| September | 76.2% | |
| October | 76.7% | |
| November | 69.6% | |
| December | 72.9% |
Monthly Wind Speed (avg max km/h)
| Month | Avg Max Wind | Bar |
|---|---|---|
| January | 21.4 km/h | |
| February | 21.9 km/h | |
| March | 23.3 km/h | |
| April | 23.5 km/h | |
| May | 21.3 km/h | |
| June | 19.8 km/h | |
| July | 18.9 km/h | |
| August | 18.4 km/h | |
| September | 18.4 km/h | |
| October | 18.6 km/h | |
| November | 20.8 km/h | |
| December | 20.4 km/h |
Monthly UV Index (avg max)
| Month | UV Index | Risk Level | Bar |
|---|---|---|---|
| January | — | — | |
| February | — | — | |
| March | — | — | |
| April | — | — | |
| May | — | — | |
| June | — | — | |
| July | — | — | |
| August | — | — | |
| September | — | — | |
| October | — | — | |
| November | — | — | |
| December | — | — |
Monthly Snowfall (cm)
| Month | Avg Snowfall | Bar |
|---|---|---|
| January | 24.2 cm | |
| February | 20.0 cm | |
| March | 9.0 cm | |
| April | 4.0 cm | |
| May | 0.0 cm | |
| June | 0.0 cm | |
| July | 0.0 cm | |
| August | 0.0 cm | |
| September | 0.0 cm | |
| October | 1.7 cm | |
| November | 0.5 cm | |
| December | 11.7 cm |
Monthly Sunshine Hours (daily average)
| Month | Avg Daily Sunshine | Bar |
|---|---|---|
| January | 5.7 hrs | |
| February | 6.6 hrs | |
| March | 8.1 hrs | |
| April | 8.5 hrs | |
| May | 10.8 hrs | |
| June | 11.4 hrs | |
| July | 11.2 hrs | |
| August | 10.7 hrs | |
| September | 8.9 hrs | |
| October | 7.8 hrs | |
| November | 7.1 hrs | |
| December | 5.6 hrs |
Frequently Asked Questions
What is the hottest month in Boston?
July is the hottest month with an average temperature of 23.8°C (74.8°F).
What is the coldest month in Boston?
January is the coldest month with an average temperature of -0.4°C (31.3°F).
What is the rainiest month in Boston?
December is the wettest month with an average of 131.7mm of precipitation. The city experiences about 161.0 rainy days per year.
When is the best time to visit Boston?
The best time to visit Boston is during July, August, June, when temperatures are comfortable and rainfall is lower.
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Data Source: Open-Meteo historical archive (2020-01-01 to 2024-12-31). Daily measurements aggregated into monthly climate normals. Coordinates: 42.36°, -71.06°. Timezone: America/New_York. Last updated: 2026-07-30.