On Monday, November 9, 2015 at 1:54:57 PM UTC, Dave Ludlow wrote:
On Mon, 9 Nov 2015 12:21:02 -0000, "Eskimo Will"
wrote:

"Graham Easterling" wrote in message
...

I think you'd also have to allow for distance from an onshore location.
(possibly a variable distance dependent on forecast wind strength?). E.g, St
Ives is currently offshore, but as the spray cloud covers the entire Land's
End peninsula, it makes little difference.

The sea state makes a difference to, there may be a lot of white water from
a big ground sea, increasing the amount of spray above the wind calculated
value. But sea state is pretty well forecast now, so building that in would
be simple enough.

I think that's about it!
=====================

An example of how things can get over-complicated, happens all the time. If
one is not careful one ends up with something that works over Cornwall and
not elsewhere. Another complication would be cliff top versus sea level
sites.
KISS :-)

Not to mention estuaries, harbours and (narrow-ish) channels.

Oh, I just did!

--
Dave
Fareham (W)

Yes, but sea spray in the air, except in really stormy conditions, is really limited to exposed areas. It's the big swell & ground sea http://www.landsendweather.info/ that is really affecting visibility today, not so much the strength of wind, which is generally only a F5, F6 over the sea. You can get summer sea breezes of F4-5.

There is so much spray in the air over Mount's Bay, you can only just make out the Mount from Mousehole (4 miles) yet the forecast visibility is still excellent http://www.metoffice.gov.uk/public/w...27?tab=fiveDay Scilly is currently reporting 9km, where the forecast is also excellent.

Visibility should be excluded from post code forecasts, unless some attempt is made to get it vaguely correct. To chose to ignore probably the most important factor affecting visibility in areas near exposed Atlantic coast is rather silly.

Graham
Penzance