What does this metar mean ?
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Pompey till I die
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From: Guildford
What does this metar mean ?
EGLF 101220Z 25005KT 1600 R24/P1500 BCFG BR OVC002 M04/M04 Q1027
I've not seen R24/P1500 before ? Is it runway 24 visibility 1500m ? If so how is that different from RVR ? I looked at the glossary but can't see anything for it.
I've not seen R24/P1500 before ? Is it runway 24 visibility 1500m ? If so how is that different from RVR ? I looked at the glossary but can't see anything for it.
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From: Hither and Thither
P does not stand for increasing!!
It indicates the RVR is in excess of the maximum that can be read for a particular runway.
D (decreasing), U (increasing) not presently used in UK, but are in rest of Europe. There is also a code for staying the same (which I cannot recall at present).
It indicates the RVR is in excess of the maximum that can be read for a particular runway.
D (decreasing), U (increasing) not presently used in UK, but are in rest of Europe. There is also a code for staying the same (which I cannot recall at present).
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From: An ATC centre this side of the moon.
P1500=Runway Visual range greater than 1500metres. The RVR is measured by a set of either visual lights or elecronically by a set of transmisometers set along the edge of the runway.......the aerodrome visibility may often be differant from the runway visibility. RVR's are usually also quoted for Touchdown, midpoint and stop end.
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From: one dot low as usual
As R4 says, it means greater than 1500m. That is the upper range of most transmissometers used so it just means that they are using them as well as tower visibility (1600m in this example) to back up the vis report.
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From: Belgium
RVR is given only when horizontal visibility (or RVR itself) is less then 1500m. If RVR is more than this 1500m. a P is added in front. Here R24/P1500.
When letters are shown after this it indicates a trend over a period of 10 mins, as correctly said by Red Four.
"There is also a code for staying the same (which I cannot recall at present)."
It is then P1500N
When letters are shown after this it indicates a trend over a period of 10 mins, as correctly said by Red Four.
"There is also a code for staying the same (which I cannot recall at present)."
It is then P1500N
Joined: Oct 2004
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From: Hunched over a keyboard
Surely there's no need to include the RVR in this METAR?
For one, at 1600m met vis then there are unlikely to be many instrument approach restrictions and second an RVR which is LOWER than the met vis (because the RVR can't read greater than 1500m) is about as useful as the proverbial chocolate teapot.
By the way, I did see chocolate teapots for sale in a sweet shop in Le Touquet a couple of years ago - I have a picture somewhere.
For one, at 1600m met vis then there are unlikely to be many instrument approach restrictions and second an RVR which is LOWER than the met vis (because the RVR can't read greater than 1500m) is about as useful as the proverbial chocolate teapot.
By the way, I did see chocolate teapots for sale in a sweet shop in Le Touquet a couple of years ago - I have a picture somewhere.
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From: EGPT/ESVS
...at 1600m met vis then there are unlikely to be many instrument approach restrictions ...
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The rules for METAR coding in the UK (which do not include all reported elements that are possible) are published in CAP 746.
On the basis of these rules the METAR in question appears to be incorrect in that the RVR value should not have been included.
The relevant extracts from CAP 746 are:
However, the rules for reporting IRVR to aircraft by ATC are slightly different. CAP 493 (a.k.a. MATS Part 1) says:
So it looks like the METAR has been coded up using the rules for passing IRVR reports to aircraft by ATC.
On the basis of these rules the METAR in question appears to be incorrect in that the RVR value should not have been included.
The relevant extracts from CAP 746 are:
- The RVR group shall be reported in the METAR only when either the minimum visibility or the runway visual range is observed to be less than 1500 metres.
- 2000 metres should be regarded as the maximum value that is possible to report. If the actual value is greater than can be reported by the runway visual range equipment or human observed method, the maximum value shall be preceded by ‘P’.
IRVR reporting to aircraft is started:
a) whenever the aerodrome meteorological report shows the visibility to be less than 1500 metres;
b) whenever the IRVR display is indicating an RVR value equal to or less than the maximum for that system;
c) whenever shallow fog is reported and during a period for which it is forecast.
a) whenever the aerodrome meteorological report shows the visibility to be less than 1500 metres;
b) whenever the IRVR display is indicating an RVR value equal to or less than the maximum for that system;
c) whenever shallow fog is reported and during a period for which it is forecast.
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From: Mumbai
TAF AMD KRIV 2705/2804 05012KT 9999 SKC WSCONDS QNH3008INS
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Can anyone explain to me what QNH3008INS means? Firtly, why is there a 3 in there? Secondly what does that INS mean?
Finally. T21/2721Z. Is that like saying temperature is 21 at 21 Zulu on 27th?
Thanks
BECMG 2716/2717 03009KT 9999 SCT200 QNH3011INS WND 320V070
TEMPO 2720/2801 03012G18KT
BECMG 2801/2802 VRB06KT 9999 SCT200 QNH3004INS T21/2721Z
T03/2715Z AMD 270511=
Can anyone explain to me what QNH3008INS means? Firtly, why is there a 3 in there? Secondly what does that INS mean?
Finally. T21/2721Z. Is that like saying temperature is 21 at 21 Zulu on 27th?
Thanks