What's the difference between a gentle and moderate breeze?

wonkywinch

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Wondering whether to go sailing on Fri or Sat (can't do both). It's a choice between a gentle breeze on Friday or moderate one on Saturday.

According to the BBC, not sure I'd even notice :cool:

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I think I wouldn’t base my decision only on a general, land-orientated forecast. The grib files show 10 knots all Friday except for 15 knots during one hour. Saturday is a solid day of 15 knots.
The reality is often 5 knots more than in the grib files.
 
I think I wouldn’t base my decision only on a general, land-orientated forecast. The grib files show 10 knots all Friday except for 15 knots during one hour. Saturday is a solid day of 15 knots.
The reality is often 5 knots more than in the grib files.
The reality in the solent has been a hard NE wind with some fairly powerful gusts for some weeks now. My forecast gives 14kn with gusts up to 20 or so. We’ve had a few quiet days, but tomorrow and Saturday won’t be the quiet ones. F4-6 is more like the truth.
 
The persistent easterlies turn around the usual plans: sailing from Portsmouth i would normally go as far west on the first day out assuming a westerly back. So heading out today, thinking of Newtown as being not as far back against the wind as say Lymington or Yarmouth?
 
Or try Met Office which shows average and gust strength, and matches Chiara's Slave forecast.
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I have been out all week (but N Wales), beautiful weather but decidedly fresh wind in the afternoons matching the local gust forecasts.

Take care to look for a forecast for the area you will sail in. For example, Bembridge shows gusts of 20 knts on Saturday versus 26 knts at Southampton. Sea breeze effects?
 
Or try Met Office which shows average and gust strength, and matches Chiara's Slave forecast.
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I have been out all week (but N Wales), beautiful weather but decidedly fresh wind in the afternoons matching the local gust forecasts.

Take care to look for a forecast for the area you will sail in. For example, Bembridge shows gusts of 20 knts on Saturday versus 26 knts at Southampton. Sea breeze effects?
No sea breeze effects with a NE gradient wind. It’s just the beastly easterlies, not at all unusual at this time of year, but maybe more persistent.
 
The reality is often 5 knots more than in the grib files.

I'm convinced that for the last two or three years winds have consistently been at the top end or above forecast. I'm sure it used to be the other way round. It used to be a F4 forecast and I'd be suspecting there might be **** all, now a F4 forecast and I'm making the kids put their oilies on.

I'm pretty sure there was a thread about it, I don't recall the conclusion.
 
I'm convinced that for the last two or three years winds have consistently been at the top end or above forecast. I'm sure it used to be the other way round. It used to be a F4 forecast and I'd be suspecting there might be **** all, now a F4 forecast and I'm making the kids put their oilies on.

I'm pretty sure there was a thread about it, I don't recall the conclusion.
Here in general I’d say you are right, unless the forecast is for lighter conditions, in which case there may be none at all.
 
It depends on the size of your boat. On my friend’s 22’er F3 gentle is a normal sailing breeze and F4 moderate distinctly bouncy, while on my 34 F3 is just enough to get moving and F4 a nice light breeze.
 
I'm convinced that for the last two or three years winds have consistently been at the top end or above forecast. I'm sure it used to be the other way round. It used to be a F4 forecast and I'd be suspecting there might be **** all, now a F4 forecast and I'm making the kids put their oilies on.

I'm pretty sure there was a thread about it, I don't recall the conclusion.
The thread I remember was about overly pessimistic gust forecasts, which apparently quite a few people experienced last year. Seeing a lot of days with "11 gusting 30" and actually getting 11 gusting 15 or so. That said, after the thread I did also experience a day forecast "18 gusting 28" which actually gave me 30+ in the worst direction near steady. I think that balanced out all the other forecasts on its own.

I've had pretty much spot on forecasts lately except that one very hot day where very little wind was forecast, but the actual wind was perfect. I'm sure I'm saving up a nice set of "that wasn't in the forecast"s for the worst possible moments. We shall see.
 
It depends on the size of your boat. On my friend’s 22’er F3 gentle is a normal sailing breeze and F4 moderate distinctly bouncy, while on my 34 F3 is just enough to get moving and F4 a nice light breeze.

We put the first reef in at about 15knots when cruising. It’s perfectly well behaved with a reef, but you really know when you need one.
 
The thread I remember was about overly pessimistic gust forecasts, which apparently quite a few people experienced last year. Seeing a lot of days with "11 gusting 30" and actually getting 11 gusting 15 or so. That said, after the thread I did also experience a day forecast "18 gusting 28" which actually gave me 30+ in the worst direction near steady. I think that balanced out all the other forecasts on its own.

I've had pretty much spot on forecasts lately except that one very hot day where very little wind was forecast, but the actual wind was perfect. I'm sure I'm saving up a nice set of "that wasn't in the forecast"s for the worst possible moments. We shall see.
My wife has a long held grudge against me for the last time we came home via the Roompot. The forecast was F4 gusting to about 15kn. The current runs at around 4kn for a short section that we knew would be a bit bumpy in these conditions but we are unprepared for a F6 on the nose and true wind in the mid 20s. The seas were monstrous by local standards and as we motor-sailed straight into them they swept across our deck in the manner of a Cape Horner. I quite enjoyed it.
 
I'm convinced that for the last two or three years winds have consistently been at the top end or above forecast. I'm sure it used to be the other way round. It used to be a F4 forecast and I'd be suspecting there might be **** all, now a F4 forecast and I'm making the kids put their oilies on.

I'm pretty sure there was a thread about it, I don't recall the conclusion.
I don’t believe general forecasts from general tv and so on.

I use a few online sources that seem accurate and really have learned to trust my barometer over many decades.
 
My wife has a long held grudge against me for the last time we came home via the Roompot. The forecast was F4 gusting to about 15kn. The current runs at around 4kn for a short section that we knew would be a bit bumpy in these conditions but we are unprepared for a F6 on the nose and true wind in the mid 20s. The seas were monstrous by local standards and as we motor-sailed straight into them they swept across our deck in the manner of a Cape Horner. I quite enjoyed it.
That sounds like the time I thought F4-6 S becoming SW was a good forecast to come home to Gosport from Weymouth in a Snapdragon 24, but the true wind was more like top of 7. Madame still hasn't forgiven me that one.
 
Must admit, at the lower end I have felt the Met office were predicting MPH not Beaufort. However at the upper end they tended to be spot on.
 
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