How Do I

[tugmistress]

FOG

ok maybe not fog as in the usual sense but a sea mist or harr rolling in?

my partner works a charter angling boat and today, the forecast bit on this site said it would be pretty good sunshine, 50% chance of thunderstorm from midday and a top temp of 27c, in reality we had 24c at 10am and then the fog rolled in off the sea and the temp levelled out approx 14c! advance warning of me being able to forecast a chance of this fog would be great as he cancelled tonights trip during this afternoons fog and now it is a lot clearer.

anyone give me a basic breakdown of what to look for or am i biting off more than i can chew?

[Paul]

An onshore breeze is certainly something to look for - also high humidity - above 70% may also be a clue.

[johnholmes]

sea fog usually shows up very well on sat piccs Paula, during the day on the visual. Infra red is not that much use. Have a look at what the surface flow is off, say, the Met O Fax charts. That will give an idea if the flow is off the sea. Perhaps somewhere down wind of you, as in most cases, sea fog in your part of the world, but correct me if I'm wrong, comes in from somewhere between east and se! Like I say correct me if I'm wrong. beyond that it gets a bit complex.

pm me if you like.

John

Edited July 21, 2006 by johnholmes

[The PIT]

Well my father was good at this.

I can remember being on the south beach at Scarbourgh and there was this wispy cloud over the hotel there. I can't describe it but if I saw it again I could say Sea fog is on the way in. My father said it's going to get foggy half n hour later it rolled in although you could see higher up before it arrived.

[Dawlish]

sea fog usually shows up very well on sat piccs Paula, during the day on the visual. Infra red is not that much use. Have a look at what the surface flow is off, say, the Met O Fax charts. That will give an idea if the flow is off the sea. Perhaps somewhere down wind of you, as in most cases, sea fog in your part of the world, but correct me if I'm wrong, comes in from somewhere between east and se! Like I say correct me if I'm wrong. beyond that it gets a bit complex.

pm me if you like.

John

John's right Tugmistress; sea fog shows up as amorphous white on a visible image. Hopeless trying to spot it at night, with the infra-red though, same difficulty as in the daytime; the haar is often the same temp as the sea below and is therefore indistinguishable from it in the infra-red - and visible image satellites don't work at night! If you can see the sea, keep your eye on the horizon - a haar can be spotted several miles off, if the horizon seems to disappear.

This morning, I awoke to hear a foghorn, out in in Lyme Bay. It's another indicator of a sea fret, out at sea. If the wind shifts to directly onshore, expect the rotten, spoiling haar!!

Paul

[tugmistress]

thanks for the replies guys B) that makes sense.

John, yes the breeze (what little we have had) has been of a easterly or southeasterly direction except for a slight swing into the NW which cleared the mist for a while the other day

the pit,

yes i know what you mean, i spent many a summer day at scarborough and bridlington and i see the same here, you can see it up high first.

paul,

that's a nice easy indicator i can use to gauge a risk, thank you

dawlish,

a fog horn would be handy but we don't have one here and i have never heard one from the lighthouse at dunnet either only off the ship itself when it comes through ha ha ha.