Meteorological data for the Netherlands, 1990-2002
The Netherlands has a maritime climate characterised by mild winters, cool summers and precipitation throughout the entire year. The prevailing wind direction is from the south-west.
| Unit | 1971/2000 | 1990 | 1995 | 2000 | 2001 | 2002 | |
| Days with precipitation | number of days | 131 | 124 | 125 | 158 | 157 | 139 |
| >= 1.0 mm | |||||||
| Snow days | number of days | 25 | 15 | 40 | 12 | 32 | 5 |
| Dry days | number of days | 109 | 127 | 131 | 91 | 105 | 134 |
| Days without sunshine | number of days | 76 | 66 | 43 | 55 | 56 | 51 |
| Fog days | number of days | 65 | 46 | 58 | 45 | 50 | 93 |
| Sunshine | hours | 1 524 | 1 622 | 1 814 | 1 515 | 1 623 | 1 688 |
| Global radiation 1) | kJ/cm2 | 347 | 366 | 366 | 338 | 359 | 362 |
| Precipitation | mm | 827 | 764 | 798 | 975 | 1091 | 988 |
| Evaporation | mm | 543 | 583 | 590 | 541 | 571 | 574 |
| Relative humidity | % | 82 | 79 | 83 | 84 | 84 | 83 |
| Ice days (max. temp <0.0oC) | number of days | 8 | 0 | 12 | 2 | 3 | 6 |
| Frost days (min. temp <0.0oC) | number of days | 58 | 33 | 61 | 35 | 66 | 40 |
| Summery days (max. temp >=25.0oC) | number of days | 22 | 32 | 41 | 22 | 24 | 18 |
| Tropical days (max. temp >=30.0oC) | number of days | 3 | 3 | 11 | 2 | 6 | 4 |
| Average of: | |||||||
| - Hourly observations (entire year) | oC | 9.8 | 11.1 | 10.4 | 10.9 | 10.4 | 10.8 |
| - Winter (1 Dec - 28/29 Feb) | oC | 3.3 | 6.0 | 5.3 | 5.0 | 4.1 | 4.8 |
| - Summer (1 June - 31 Aug) | oC | 16.6 | 16.8 | 18.2 | 16.3 | 17.4 | 17.6 |
| Averaged daily minimum temperatures in winter (1 Dec - 28/29 Feb) | oC | 0.4 | 3.2 | 2.3 | 2.1 | 1.3 | 1.7 |
| Averaged daily maximum temperatures in summer (1 June - 31 Aug) | oC | 21.4 | 21.9 | 23.4 | 21.1 | 22.4 | 22.3 |
| Number of degree days 2) | number of degrees | 3 075 | 2 677 | 2 916 | 2 659 | 2 880 | 2 720 |
| Source: KNMI (2003a, 2003b). | CBS/EDC/May03 | ||||||
| N.B. All figures are for De Bilt. 1) The amount of solar radiation reaching the earth's surface. 2) Degrees under the heating degree threshold (=18oC), on the basis of the average daily temperature in De Bilt. | |||||||
Interaction between climate and the environment
The Netherlands has a maritime climate characterised by mild winters, cool summers and precipitation throughout the entire year. The prevailing wind direction is from the south-west. The weather can have a direct impact on the environment. A few examples are:
- Cold winters (with persistent snow on the ground) affects bird migration patterns.
- Air circulation plays an important role in the creation of smog and odour nuisance.



