The season goes from April to November. In that time air from spring 10-20°C, in summer up to 30°C and autumn 10-16°C. Water spring 8-13°C, summer 18-23°C, autumn 8-14°C. You always need a wetsuit. You can go out off-season but it will be very cold, a thick wetsuit or better drysuit, mask, shoes and gloves recommended.
Drive from Aalborg towards Egense. Then follow the signs towards Øster Hurup. Just before the city there is a camping place. This is where you park and start from. From the south take 507 north, then 541 east towards Visborg, then Als and then Øster Hurup to the camping place.