Climate averages 1991–2020
Haarlem weather
in September.
A mild, moderately wet month: the 4th warmest and the 10th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
September is a mild month in Haarlem: daytime highs average 17.7°C and nights cool to about 13.2°C. By daytime temperature it is the 4th warmest of the 12 months.
Expect about 84 mm of rain on roughly 13 days, which makes September a moderately wet month (the 10th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 44 min on an average September day.
The nearest other city in this atlas is Hoofddorp (9 km away). In September its highs average 17.9°C, about as warm as Haarlem, with 81 mm of rain.
Among the 44 cities listed in the Netherlands, Haarlem ranks joint 41st of 44 for the warmest September highs and joint 41st of 44 for the driest September (rainfall, lowest first). The mean September high of those 44 cities is 18.4°C; Haarlem is 0.7°C cooler than that mean.
From September to October, average highs fall by 3.8°C to 13.9°C, and monthly rainfall rises from 84 mm to 88 mm.
The annual picture
September in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Haarlem climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 5.8°C2.5°C | 2.5°C | 69 | 13.2 | 8.38 h |
| February | 6.1°C2.3°C | 2.3°C | 54 | 11.0 | 9.910 h |
| March | 8.6°C3.9°C | 3.9°C | 52 | 10.7 | 11.812 h |
| April | 12.0°C6.3°C | 6.3°C | 44 | 10.1 | 13.914 h |
| May | 15.3°C9.8°C | 9.8°C | 58 | 10.4 | 15.716 h |
| June | 17.8°C12.7°C | 12.7°C | 63 | 11.3 | 16.717 h |
| July | 20.0°C15.1°C | 15.1°C | 79 | 13.0 | 16.316 h |
| August | 20.3°C15.4°C | 15.4°C | 90 | 13.3 | 14.715 h |
| September, selected | 17.7°C13.2°C | 13.2°C | 84 | 12.7 | 12.713 h |
| October | 13.9°C9.9°C | 9.9°C | 88 | 14.1 | 10.711 h |
| November | 9.6°C6.3°C | 6.3°C | 77 | 14.8 | 8.89 h |
| December | 6.6°C3.5°C | 3.5°C | 79 | 14.2 | 7.88 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
September in nearby cities
- Hoofddorp in SeptemberThe Netherlands · 9 kmHigh 17.9°C · Low 13.0°C · 81 mm rain
- Zaandam in SeptemberThe Netherlands · 14 kmHigh 17.9°C · Low 12.9°C · 84 mm rain
- Zaanstad in SeptemberThe Netherlands · 14 kmHigh 17.7°C · Low 13.1°C · 84 mm rain
- Amsterdam in SeptemberThe Netherlands · 17 kmHigh 17.9°C · Low 12.5°C · 69 mm rain
- Amstelveen in SeptemberThe Netherlands · 18 kmHigh 18.1°C · Low 12.3°C · 81 mm rain
- Purmerend in SeptemberThe Netherlands · 26 kmHigh 17.9°C · Low 12.6°C · 69 mm rain
- Leiden in SeptemberThe Netherlands · 27 kmHigh 18.0°C · Low 12.9°C · 87 mm rain
- Alphen aan den Rijn in SeptemberThe Netherlands · 28 kmHigh 18.3°C · Low 12.1°C · 81 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Haarlem) is explained once on the Haarlem year overview and on the Sources, method and limits page.
Zaanstad and Zaandam lie in the same rainfall cell, so their rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.