Weeronline says mostly dry and sunny weather is expected for the first half of June, but temperatures can fluctuate a lot. Later in the month, the chances of showers increase and it gets warmer.
Temperatures can stay between 15 and 18 degrees Celsius, especially in coastal areas, due to north-northeast winds. When the wind blows from the east, the temperature can rise to 20 to 25 degrees. The southeastern and eastern regions are most likely to have summer days with maximum temperatures above 25°C. According to Wheelonline, even the west coast has an easterly wind, so while the sea temperature is only about 14 degrees Celsius, it’s still warm enough for a day on the beach.
In the second half of June, the easterly wind will warm the air, so there will be more rain such as thunderstorms and torrential downpours. Weeronline says temperature forecasts are uncertain at this time because the sun will be hard to beat at that time. However, the Bureau of Meteorology expects dry, clear skies to persist for most of the time.
https://nltimes.nl/2023/05/28/dry-sunny-early-summer-expected-june-netherlands A dry and sunny early summer is expected in the Netherlands from June