this morning, surrounded by mild temperatures..
EGPE 020620Z 00000KT 0300 R23/0550 R05/0900 FZFG OVC001 M00/M00 Q1022=

Quite an active trough in the Mediterranean at the moment.

Phil


--

http://homepage.ntlworld.com/phil.layton/meteo.htm

"Phil Layton" wrote in message ...
this morning, surrounded by mild temperatures..
EGPE 020620Z 00000KT 0300 R23/0550 R05/0900 FZFG OVC001 M00/M00 Q1022=

Freezing fog, as Air Trafficers and Pilots know only too well, is one
of those phenomena we can well do without. But perhaps my biggest
hate of all is freezing rain.

That report from Inverness certainly takes me back some seven or eight
years. We needed 150 metres for take off (as best I can recall -
amazing, I have only been retired 6 years, but have totally forgotten
the details of the regulations). The fog kept thinning to 175 then
thickening to 100 (it wasn't the freezing variety thank goodness) and
finally we got off when it had been 200 metres for the first two
runway segments for a couple of minutes. The following aricraft was
delayed some while after the fog thickened again - I guess our engines
had stirred it up! What I do recall very well was the marvellous view
after we had taken off shortly after dawn, of the fog filled valleys
in and around the Cairngorms. That's the sort of thing I miss most of
all. Still, I do fly my glider from time to time, but not normally
when the visibility is 200 metres :-)

Jack

"Jack Harrison" wrote in message
m...
That report from Inverness certainly takes me back some seven or eight
years. snip


Jack,
In 2004, we have been lucky regarding FG, let alone FZFG.

In January, there was just 1251mins delay - mainly at STN
Feb, 189mins at STN & LCY
March up to 12,976mins mainly on 4th and 5th at LHR LGW LCY BHX
April 3,812mins
May 6,594mins
June nil
July 483mins at LGW on 16th/22nd
Aug nil
Sep nil.

So bearing in mind that one day while I was in leave recently, LHR had
11,000mins - its been a fog free year - so far!

Phil

"Phil Layton" wrote in message
...


Jack,
In 2004, we have been lucky regarding FG, let alone FZFG.

snip

Phil, remind me, do LVPs come into force from the beginning of the period of
a fog warning or are they governed by current conditions alone ?

Heathrow certainly did well on Saturday night to escape the worst of the low
cloud/poor vis that was around.

Cheers,
Jon.

Just a reminder that in a METAR, freezing fog does not necessarily mean
'fog depositing rime' .. as in the SYNOP. As long as the temperature is
sub-zero, then the fog must be coded as 'freezing'; just because the air
temperature is below 0degC, doesn't mean that ice is being deposited - a
lot depends upon how long the temperature has been below zero, what the
thermal capacity of the particular surfaces under consideration are etc.

Martin.


--
FAQ & Glossary for uk.sci.weather at:-
http://homepage.ntlworld.com/booty.weather/uswfaqfr.htm

In article ,
Phil Layton writes:
So bearing in mind that one day while I was in leave recently, LHR had
11,000mins - its been a fog free year - so far!

The days at LHR must be longer than elsewhere, containing upwards of 180
hours!
--
John Hall
"If a man will begin with certainties, he shall end in doubts;
but if he will be content to begin with doubts,
he shall end in certainties." Francis Bacon (1561-1626)

"Jon O'Rourke" wrote in message
...
Phil, remind me, do LVPs come into force from the beginning of the period
of
a fog warning or are they governed by current conditions alone ?

LVPs come into force when the RVR is 600m or cloud ceiling 200ft or less.
That said, Traffic Managers do sometimes apply a regulation on the basis of
a forecast :-) which can bring delays even if LVPs do not materialise.
Fog warnings per se are not really useful to us, as they do not recognise
the LVP criteria (as they are looking for a vis less than 1000m? but no
reference to cloud) and they often arrive after the fog has formed - but
we'll put that down to the AFTN :-)


Phil

"John Hall" wrote in message
...
The days at LHR must be longer than elsewhere, containing upwards of 180
hours!
--
John Hall

Believe me John, they feel that long sometimes! - you have to divide that by
the 650 planes that land there each day - perhaps I should have mentioned
that the wind was the attribution on that occasion.

Phil

"Phil Layton" wrote in message
...

LVPs come into force when the RVR is 600m or cloud ceiling 200ft or less.
That said, Traffic Managers do sometimes apply a regulation on the basis
of
a forecast :-) which can bring delays even if LVPs do not materialise.
Fog warnings per se are not really useful to us, as they do not recognise
the LVP criteria (as they are looking for a vis less than 1000m? but no
reference to cloud) and they often arrive after the fog has formed - but
we'll put that down to the AFTN :-)

Thanks for that, Phil. Airfield fog warnings are issued for a (met.)
visilbility of 600m or less and I would hope are normally issued well before
any fog materialises at the airfield, thus it's somewhat disappointing to
note they're not really useful to you. Certainly a warning should be out in
advance if fog is in the short TAF and on occasion a warning will be issued
when fog isn't in the TAF, i.e. the risk is considered significant but 30%.

Jon.

In article ,
Phil Layton writes:

"John Hall" wrote in message
...
The days at LHR must be longer than elsewhere, containing upwards of 180
hours!

Believe me John, they feel that long sometimes! - you have to divide that by
the 650 planes that land there each day

Ah, I see. So the units aren't really minutes but what one might call
plane-minutes.

- perhaps I should have mentioned
that the wind was the attribution on that occasion.

Now you've lost me, I'm afraid.
--
John Hall
"If a man will begin with certainties, he shall end in doubts;
but if he will be content to begin with doubts,
he shall end in certainties." Francis Bacon (1561-1626)