Fog in the Channel

[Allan]

We sailed from Cardiff to Wacthet on Saturday, via a lunch stop at Minehead. We saw some fog west of the Holms in the morning, as predicted. After tying up in Watchet we went for a walk on the coast path and at 6ish saw loads of fog all around the channel. This was not forcast on the VHF at all during the day, does it happen often?
I have sailed quite a few times around various parts of the Channel and not seen it before. Are there any particular weather conditions that cause it to form? I had a handheld VHF with me on the walk and heard the Swansea Coastguard talking to someone about it, he gave it a name which I didn't catch.
Allan

 

[sb99]

We went over to Watchet Saturday, arrived at 5.25PM. Amazing how quick that fog came down, glad we missed it.
I still need to do a lot of work on interpreting those Bristol Channel forecasts.
Came back to Cardiff on early tide Monday, straight over to Mermaid Quay for breakfast, then back on the boat for mid morning nap. Stayed a while for the festival, overall a nice weekend. /forums/images/graemlins/cool.gif

 

[damo]

I came down from Portishead to Cardiff on Saturday morning, and the fog was rising in the Gordano valley as I entered the lock. By the time I'd got round to Battery Point the vis was down to about 100-200m, and the large car vessel that had just locked out of Portbury was worried about the small craft. Some of us were appearing on radar, while another wasn't, so he was going dead slow and sounding his horn, which was good to know.

We crept down the edge of the channel inshore, which is disconcerting on a falling tide and no chartplotter, then saw him briefly in a short clearance, so I was able to cross over to the Welsh side OK. It didn't clear until we were almost to Cardiff.

I don't think it matters what navaids you have - thick fog is worrying, especially when you know that the tide is sweeping you down to the next buoy and you won't see it until you are about 30secs away.

 

[Allan]

We saw what I think must have been the same car carrier just after we rounded Rannie point. We were able to stay out of the fog by hugging the Welsh coast for a little longer than normal. By the time we had to cross it had lifted. The later fog arrived really quickly, luckily we were in Wachet by then.
Allan

 

[duppamiller]

Fog's scary when you're on the water - but even more so when you're in the air!

As a result the airport's are pretty hot on their visibility forecasts and conveniently we have one on either side of the (upper) channel. Unfortunately the Met Office use a form of gobbledygook for their aviation forecasts (called TAF's) and actuals (METAR's) but this site can translate them into English:

http://adds.aviationweather.gov/metars/index.php

If you enter 'EGGD EGFF' into the text box and check the 'TAFs' and 'Translated' boxes and click on 'Submit' then it'll return an actual and a forecast for both Bristol and Cardiff airports. It's a bit convoluted and you have to bear in mind that the airports are inland and higher than the channel, but they are extremely accurate (although of course not infallible) and will even include a probability factor if they're not completely sure.

If you're feeling adventurous then click on the 'stations.txt' link and you'll see that this system covers just about every airport on the planet - so if like me you've got friends holidaying on the Algarve you'll see that it was 21 degrees C at 0800 (Faro), and that a sea breeze will kick in during the afternoon - not fair!