Climate Insights for Haarlem

The climate in Haarlem is temperate. The average annual temperature is 16°C and approximately 492mm of precipitation falls per year. September is the wettest month, receiving around 59mm of rainfall. Haarlem is in the Southern Hemisphere. The seasons are reversed — summer runs from December to February, while winter falls between June and August. The summer months are: January, February, March. The coldest months are July, August, June, when temperatures can drop to 5°C.

Temperatures in Haarlem vary considerably across the year, with a 22°C difference between the coldest and warmest months. The warmest month is January, when average highs reach 27°C and the mean temperature sits around 20°C. July is the coolest month, with minimum temperatures around 5°C and an average of 11°C. On average, daily temperatures fluctuate by about 12°C between overnight lows and afternoon highs. The sharpest temperature change occurs between March and April, with a 3°C shift in average temperatures.

Haarlem is a relatively dry area, receiving approximately 492mm of precipitation annually, which averages out to around 41mm per month. The wettest month is September, averaging 59mm of rainfall. November and February also tend to see above-average precipitation. The driest month is May, with just 27mm. That's 32mm less than September, the wettest month. Rainfall is relatively evenly distributed throughout the year, so there is no pronounced dry or wet season to plan around.

Haarlem is mildly breezy, with an average annual wind speed of 16km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is December, averaging 17km/h, though still comfortable for most outdoor activities. The calmest conditions occur in May, with average winds dropping to 13km/h, making it an ideal period for wind-sensitive activities. Wind conditions are fairly consistent throughout the year, varying by only 4km/h between the calmest and windiest months.

It is currently autumn in Haarlem, which began on March 20, 2026. Haarlem is in the Southern Hemisphere, where the seasons are reversed — spring starts in September, summer in December, autumn in March, and winter in June. The warmest period peaks in January at around 27°C, while the coldest stretch bottoms out in July near 5°C. Winter is next, beginning on June 21, 2026 — 89 days from now.

The best time to visit Haarlem is during January, February, March, April, October, November and December, when the weather is most comfortable for travellers. During these months, average temperatures hover around 18°C with modest rainfall averaging 42mm per month. By contrast, July can be quite cold with temperatures dropping to 5°C. A light rain jacket is recommended, though showers are generally brief and shouldn't disrupt your plans.

The table below shows monthly climate averages for Haarlem 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. 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.