Although the Olympic Centre at Weymouth can be a great venue to sail in Weymouth Bay, most of the Championships I have raced there, have been mostly been sailed inside the Harbour. This was true of the Laser Nationals, RS300 Nationals, LDC 2000 Nationals and numerous qualification events over the years.
The harbour is rather large and can often have more wind than the bay, but there are some quirks that you might want to take note of:
Wind from the:
Tide - negligible in the harbour, check the buoys in the area as you sail out but less than 3/4 kt (maximum near the gaps in the harbour wall.
North - If the wind is light, the wind can bend around the Nothe point giving a right-hander at the NW section of the bay. Likely to oscillate from the land so track the wind. It will be gusty.
East - Clean wind May move right on a sunny day (rare to get a SE sea breeze) but possible enhancement if easterly gradient might get waves/swell near entrances.
South East - Portland starts to play a role, the east side of the harbour will have cleaner wind than the right, wind shadow near the academy area, prominent wind bend around the Bill, left-hander at the top of the beat
South - Wind will bend around the bill, depending on how south the breeze is the East side of the harbour will be very light and patchy best bet to go middle right and play the shifts.
South West - Compression effect and bend off the bill, top left always good, hard right never pays, you will steadily head off the line tack to take advantage of the shift on port to the mark, Keep on the bill side downwind.
Sea Breeze - sets in around 210 and moves slowly right to 240 and can get fresh, bends as per the detail above
West - Clean wind with pulses of breeze (rolling over the causeway) If in the northern part of the harbour you may get influence from the land to the north.
North West - Gusty and shift as it rolls off Weymouth and the hills, Gust and Shift sailing, eyes out of the boat for pressure
I hope you enjoy your RS Games at Weymouth and now at least you have something to think about if you find yourself racing in the harbour.
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