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ralphmalph
24th Mar 2006, 20:25
EGPA 242050Z AUTO 11022G32KT 9000NDV SCT020/// BKN031/// 05/01 Q1002

Been reading these AUTO reports for a while......

Does anyone know what NDV stands for?? and what the /// stand for after the cloud bases?....

Cheers

Ralph

cl12pv2s
24th Mar 2006, 21:24
NDV= No Directional Variation....of visibility sensors. Used if its an automated station.

/// denotes that the 'automated' station cannot detect the 'type' of cloud group at this level.

cl12pv2s

FYI:

o Although all possible types of present weather cannot be coded automatically, equipment is developing and new
codes are appearing in the METAR AUTO: DZ or FG or BR or RA or SN or FZFG or SHRA or SHSN or FZRA or FZDZ.
o The abbreviation UP is used to indicate when it has not been possible to identify precipitation using the automatic observation
system.
o The attribute VC (vicinity) is not normally used by automatic systems; however certain sites can code VCTS (thunderstorms
close to airfield, i.e. between 8 and 16 km from the airfield).
o The symbol /// is inserted after the cloud code group to show that the type of cloud cannot be observed by the automatic
system.
o The abbreviation NCD is inserted in place of the cloud code group when no cloud has been detected by the automatic
system and when the system is not capable of detecting the absence of CB or TCU.
o The abbreviation NSC is inserted in place of the cloud code group when the automatic system has not detected any
cloud and the system is capable of detecting the absence of CB or TCU.
o The symbol ////// is used in front of CB (or TCU) where the automatic system has detected a CB (or TCU) and where
the coverage (or height) of these clouds has not been measured.
o The abbreviation REUP should be used to indicate that the automatic system has been unable to identify a recent precipitation.

havoc
24th Mar 2006, 21:30
Best answer I could find


http://homepage.ntlworld.com/booty.weather/metinfo/codes/METAR_decode.htm

EGZZ 231020Z 02006KT 4000 0900NE R27/0600U R32/0150D PRFG OVC007 12/11 Q1028
4000 .. 0900NE .. The first figure given is the 'prevailing visibility', which can be regarded as the 'best' figure that can be applied to at least 50% of the horizon (contiguously or otherwise). So, for example, if the visibility varies from 8km down to 4000m for at least half of the visible horizon, the prevailing visibility is 4000m. It is important to note that the visibility may be lower than this figure elsewhere, but for deviations to be reported, they must obey certain rules: if the visibility in one particular direction is less than 1500m or is less than half of the prevailing figure, then the lowest visibility observed (900m in above) is reported, with the direction shown (NE). If the lowest value applies in several directions, then the 'most operationally significant' direction is given. If the visibility is fluctuating wildly (e.g. rapid shower transistion), then only the lowest visibility is reported. Where the observation is a fully-automated one (e.g. an 'AUTO' ob.), then no variation with direction of visibility is usually possible, and the letter-group NDV is appended to the visibility value.

ralphmalph
24th Mar 2006, 21:31
cl12pv2s

Thank you for you help....you would not believe how many 'professionals' were confused/could'nt be arsed to answer this question.

Many thanks

Ralph

cl12pv2s
24th Mar 2006, 21:57
No probs...

These automated weather stations are great, but only if one knows the limitations of them.

A human observer may include VCTS in the metar just by looking out of the window. Just because the automated station does not include this code, it doesn't mean that there aren't thunderstorms about (unless coded thus).

As with any weather source, it is not enough just to be able to read the source...you need to know how and when it was collected too!

cl12pv2s

chevvron
25th Mar 2006, 08:15
Use the dial up service on 09063 - 800 - 400 and you don't have to do this decode.

Sailor Vee
25th Mar 2006, 12:37
Why would you be interested in Kirkwall any way?

Geoffersincornwall
25th Mar 2006, 16:08
Having just read the rather humorous 'German' thread I'm minded to continue the homour theme with METAR codes that we would like to add to the list, like:

WSGH - Weather ****e go home
YMBJ - You must be joking
TBFH - Too bad for helicopters
RRRR - Ideal weather for Robinson pilots who don't want to kill themselves
RRR - Not quite so ideal
RR - Dodgy, definitely needs careful thought
R - Good day for yet another Robinson suicide

G:)

remote hook
25th Mar 2006, 16:34
That's funny.

RH

just short
25th Mar 2006, 18:15
Are robinsons notoriously bad in cold weather then. If so, what do you have to watch out for ?

Oogle
25th Mar 2006, 18:57
Interesting to note the subtle differences between the UK and Aus.

In Australia, //, /// or //// indicates a report from a fully automated AWS that does not include information from sensors for vis, weather or cloud.

22clipper
26th Mar 2006, 02:30
Interesting to note the subtle differences between the UK and Aus.

In Australia, //, /// or //// indicates a report from a fully automated AWS that does not include information from sensors for vis, weather or cloud.

Can anyone tell me in this broadband age why we have to put up with obscure abbreviations more suited to the morse key era anyway? A few more 'actual weather' web cams would do me nicely.