Portland Harbour works best in Southwest and West winds. This gives a sideoffshore and offshore wind, resulting in silky flat conditions parallel to the pebble beach. Easterly winds gives onshore conditions and lots of chop. The wind is very gusty and unusable on anything North, Northwest and South. This is because the wind passes over the island of Portland on a southerly and over the mainland on anything with North in it.
Kiting is restricted to low tide only on Easterlies and not allowed at high tide (due to kite flying towards the road). When flying on lows and Easterly then kiters should remain at least 3 kite lengths off the beach.