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Old December 4th 04, 06:23 PM posted to uk.sci.weather
Jon O'Rourke Jon O'Rourke is offline
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"Julian Scarfe" wrote in message
...
snip

Well it *is* evident, but it looks like many of the observers haven't read
the rubric carefully enough. :-)


I've seen few, but not many and I'm sure it's not being used on 99% of
occasions when it should be (Heathrow excluded).
Although I should add that there's still quite a few airfields (like Gatwick
IIRC) who have yet to switch to the new practice.


METAR EGNH 290920Z 09005KT 9999 9000E VCFG FEW030 00/M01 Q1022=
METAR EGGD 302120Z 10007KT 9999 7000SE BKN063 05/04 Q1009=
METAR EGGW 031250Z 21004KT 5000 3000S BR SCT076 04/04 Q1022=
METAR EGFF 041320Z 25008KT 9999 8000N FEW007 SCT008 BKN016 10/09 Q1030=

The directional vis should only be reported if less than 50% of the prev
vis, or 1500 m.


Oh dear.


An early issue at EGLL
EGLL 281550Z 33008KT 290V010 9999 7000NW -RADZ FEW009 SCT012 OVC020 06/04
Q1011 TEMPO 4000 BKN009=

but nothing naughty since. I doubt the world will come to an end if
unnecessary extra vis fields are included!


Probably not, but I suspect additional vis filelds will be the exception
rather than the rule at most airfields. Not least because the equipment only
provides a single vis and the lower directional vis requires a look out the
window.. allegedly ;-P

Jon.