"Jon O'Rourke" wrote in message
...
The new rules being put to good use at Heathrow this morning..

EGLL 040920Z 31001KT 3500 1500W BR BKN040 06/05 Q1029 NOSIG
EGLL 040850Z 28001KT 3500 1500W BR FEW000 BKN042 06/05 Q1029 TEMPO 1200
EGLL 040820Z 27002KT 3500 1200W R27L/P1500 R27R/P1500 BCFG BR FEW000
SCT025
BKN042 05/05 Q1029 NOSIG
EGLL 040750Z 28003KT 3500 0800W BCFG BR FEW000 BKN038 05/05 Q1029 TEMPO
2000
BR
EGLL 040720Z 28003KT 3000 0800W BCFG BR FEW000 SCT002 BKN038 05/05 Q1028
TEMPO 1200 BKN002
EGLL 040650Z 28004KT 4300 2000W BR FEW003 BKN038 05/05 Q1028 TEMPO 1500
BKN003
EGLL 040620Z 27004KT 4700 2300SW BR FEW003 BKN038 05/05 Q1028 TEMPO 1200
BKN002

Prevailing vis strangely not evident in many other obs, most puzzling,
*cough*.

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

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.

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!

Julian