Racing & sea breezes

snowleopard

snowleopard

Well-Known Member
Joined
16 May 2001
Messages
33,645
Location
Oxford
Visit site
Taking part in a race from Plymouth to the Eddystone this w/e. It promises to be ghosting conditions and sunny. I was wondering when the sea breeze is likely to kick in and how far offshore the effects are likely to be felt. The cliffs are around 200 ft along here so skimming along the beach is probably not a good tactic.

I'd normally just start the donks in this weather but I guess it might be frowned on.
 
Twister_Ken said:
Good question. I know where I'd want to be with a flat coastline - just off the beach once it was established, but what effect will the cliffs have?
Click to expand...

Undoubtedly. There will be a "wind shadow" to windward of them as the breeze separates from the water to head over the cliffs. I've heard a rule of thumb of wanting to be at least 10 times the height of the cliffs away from them.
 
flaming said:
Undoubtedly. There will be a "wind shadow" to windward of them as the breeze separates from the water to head over the cliffs. I've heard a rule of thumb of wanting to be at least 10 times the height of the cliffs away from them.
Click to expand...

On that rule of thumb I'd want to be at least 1/2 mile off which is no hardship as I have to come out to round Rame Head on the way back but I wonder how far offshore it is safe to go - I guess it will vary as the land warms up.

The cliffs are a slope of 45° ish. I have seen paragliders hovering 20 or 30 feet above the cliff tops riding the breeze coming up the slope.
 
I don't think you can tell until the sea breeze starts developing to be honest. Sounds very much like a day to keep your eyes out of the boat and look for clues around you, whether that's other boats under sail, breeze lines, smoke from cargo ships or whatever.
 
Get yourself a copy of this: it's just come out.

http://www.amazon.co.uk/Seabreeze-Handbook-Marvel-Seabreezes-Advantage/dp/1408145561

9781408145562.jpg


One of the more amazing things I discovered from the book is that in perfect conditions, the seabreeze can make it to Reading.
 
Last edited:
Keen_Ed said:
One of the more amazing things I discovered from the book is that in perfect conditions, the seabreeze can make it to Reading.
Click to expand...

I've certainly felt its effect there - made me wish I was closer to the coast.

To the OP: if the wind starts out really flat and patchy, looking for the best wind from deck level only tells part of the story as you really can't see much of the surface of the sea. Getting someone to occasionally climb even just a short way up the rig - 10ft makes a big difference - will give you a much better picture of where the best wind - and the biggest holes - are at any given time.
 
flaming said:
This is a pretty good guide.
http://www.sailingworld.com/article/Four-Ways-to-Win-the-Sea-Breeze-Game
Click to expand...

Good article

Tho i thought that a land breeze was when the wind headed to the land (ie when land hotter than sea during daytime) and sea breeze was opposite (usually at night when sea hotter than land) tho maybe i am mis remembering my school geography?

Anyway, have been sailing a dinghy for last two weeks around yealm/noss mayo - if i get up at 5ish there is often a fair sea breeze, tho p'haps this is the underlying predicted easterly wind and combination of funnelling down yealm estuary come from north. (high pressure) and for the first week often had a good land breeze from south in the afternoon, but not so predictable in the afternoon during 2nd week (this week).

Anyway ahve a good race at the weekend, alas we have to drive home :-)
 
bikedaft said:
Good article

Tho i thought that a land breeze was when the wind headed to the land (ie when land hotter than sea during daytime) and sea breeze was opposite (usually at night when sea hotter than land) tho maybe i am mis remembering my school geography?

Anyway, have been sailing a dinghy for last two weeks around yealm/noss mayo - if i get up at 5ish there is often a fair sea breeze, tho p'haps this is the underlying predicted easterly wind and combination of funnelling down yealm estuary come from north. (high pressure) and for the first week often had a good land breeze from south in the afternoon, but not so predictable in the afternoon during 2nd week (this week).

Anyway ahve a good race at the weekend, alas we have to drive home :-)
Click to expand...

The convention with naming wind directions is that it is called where it is coming from, for example ,when the wind is coming from the west we say it is a westerly. So when the wind comes from the sea it makes sense to call it a sea breeze.
 
You must log in or register to reply here.

Share this page

Top