Ghent
If you're hunting for hidden treasures, this is it.
Ghent is a small city with 297 bars, 50.000 students, an alive music scene with free concerts every day, good secondhand shopping, very relaxed natives and almost no cannibals. The city lies between Bruges and Brussels, and that's also what it feels like: you get a romantic setting with pretty medieval buildings (like Bruges) mixed up with a living nightlife (like Brussels).
This city is not well known, but really worth a night or two.
THIS IS THE WEATHER IN GHENT RIGHT NOW:

White cloud
Max Temp: 14°C (57°F)
Min Temp: 10°C (50°F)
TWO DAY FORECAST:
- Friday: white cloud, Max Temp: 17°C (63°F), Min Temp: 13°C (55°F)
- Saturday: sunny intervals, Max Temp: 19°C (66°F), Min Temp: 13°C (55°F)