In Belgium, falls are quite rainy and already a bit cold. Winters are grey with temperatures near 0° Celsius (but not usually much colder than that) and not a lot of snow. Spring is very variable, but lately (last 2 years) spring has been very nice with lots of sunshine. Summers can be quite disappointing and rainy with only a few really nice days. So go around springtime, when the weather is nice and not too hot or rainy, like right now (it is now March 27 and the temperature reached 19° Celsius today, and the sun shined all day long) but mornings and evenings can still be quite cold around that time, so remember to take something a bit warmer on your trip as well.

 

This is a link to:

Antwerp Weather Info - 5 Day Forecast