Climate Insights for Greenwich

The climate in Greenwich is cool. The average annual temperature is 9°C and approximately 1162mm of precipitation falls per year. Greenwich receives a notable amount of rainfall throughout the year, including during its driest month. Greenwich is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: July, August, June. The coldest months are January, February, December, when temperatures can drop to -7°C. Greenwich experiences heavy snowfall, typically from January through December.

Temperatures in Greenwich vary considerably across the year, with a 35°C difference between the coldest and warmest months. The warmest month is July, when average highs reach 28°C and the mean temperature sits around 23°C. The coldest month is January, when overnight lows fall to -7°C and the daily average is -4°C. On average, daily temperatures fluctuate by about 9°C between overnight lows and afternoon highs. The sharpest temperature change occurs between October and November, with a 8°C shift in average temperatures.

Greenwich is a moderately rainy area, receiving approximately 1162mm of precipitation annually, which averages out to around 97mm per month. The wettest month is October, averaging 135mm of rainfall. April and November also tend to see above-average precipitation. The driest month is September, with just 78mm. That's 57mm less than October, the wettest month. Rainfall is relatively evenly distributed throughout the year, so there is no pronounced dry or wet season to plan around. Greenwich receives heavy snowfall, accumulating around 202cm annually from January through December. The snowiest month is February, with approximately 46cm. Winter travel should account for significant snow cover.

Greenwich is relatively calm, with an average annual wind speed of 3km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is March, averaging 3km/h, though still comfortable for most outdoor activities. The calmest conditions occur in August, with average winds dropping to 2km/h, making it an ideal period for wind-sensitive activities. There is moderate seasonal variation in wind speed, with a 1km/h gap between the calmest and windiest months.

It is currently spring in Greenwich, which began on March 20, 2026. Greenwich is in the Northern Hemisphere, where spring begins in March, summer in June, autumn in September, and winter in December. The warmest period peaks in July at around 28°C, while the coldest stretch bottoms out in January near -7°C. Summer is next, beginning on June 21, 2026 — 7 days from now.

The best time to visit Greenwich is during June, July, August and September, when the weather is most comfortable for travellers. During these months, average temperatures hover around 20°C with modest rainfall averaging 83mm per month. By contrast, January can be quite cold with temperatures dropping to -7°C. Despite being the best months overall, some rain is still likely — pack a waterproof layer and plan a mix of indoor and outdoor activities.

The table below shows monthly climate averages for Greenwich based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Snow is measured in centimetres (cm) and reflects average monthly snowfall accumulation. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.