Talk:METAR

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I removed airline because all pilots use METARs, not just airline pilots. bDerrly talk contr 14:05, 21 July 2005 (UTC)

Good edit. I missed that when I wrote it originaly :-) - Ottergoose 14:57, 21 July 2005 (UTC)

--Ymorby 22:42, 9 January 2006 (UTC) Added runway status information (9949//91) Information retrieved from Meteo France and translated into english

--Perhaps it's best not to mention the RMK section in any detail, because it is basically an undefined section where countries can add whatever they want - the US chooses to use it in the way described. Also, METARs are reported half-hourly from many airports, not hourly - in the UK half-hourly is the norm BaseTurnComplete 02:46, 21 February 2006 (UTC).

The point of having the two examples (which were deliberate made as different as possible while trying to hold a few likenesses to show similarity) is to give the range of possibilities. I have no problem with adding more examples, or even creating an entire page dedicated to the nuances of METAR code. Famartin 05:39 21 February 2006 (UTC).

--Famartin 06:14 14 February 2006 (UTC): Removed edits of previous wikipedian in the US/Canada METAR code. First, the comment about temperature is inaccurate: US ASOS systems are designed to be accurate to the nearest degree Fahrenheit, so they DO have that amount of accuracy.

But the remarks section expresses them to the nearest tenth of a degree Celsius, not in whole degrees Fahrenheit. That is much greater precision than whole degrees Fahrenheit (0.1 °C = 9/50 °F); most (especially those which use the remarks temperatures) do not really have that 0.1 °C accuracy. It is false precision, creating the impression that the numbers are more precise than they actually are. 66.97.236.230 07:21, 14 February 2006 (UTC)

Second, not all of the RMK section is not duplicated in Canada. They do have remarks in Canada, including SLP... here's an example: METAR CYYZ 130800Z 29016KT 15SM FEW026 BKN067 M03/M07 A2977 RMK SC2AC5 SLP090=

They do have remarks in Canada, but there are absolutely no international standards for what comes after the remarks section. 66.97.236.230 07:21, 14 February 2006 (UTC)

To illustrate my point, here are 24 hours of reports for the Trenton, NJ airport used as an example:

     KTTN 130753Z 28004KT 10SM CLR M07/M13 A2985 RMK AO2 SLP106 T10671128 $
     KTTN 130853Z 23003KT 10SM CLR M09/M13 A2987 RMK AO2 SLP110 T10941128 51015 $
     KTTN 130953Z 24004KT 10SM CLR M08/M13 A2989 RMK AO2 SLP119 T10831133 $
     KTTN 131053Z 26003KT 10SM CLR M09/M13 A2991 RMK AO2 SLP126 T10891133 $
     KTTN 131153Z 24005KT 10SM CLR M09/M13 A2993 RMK AO2 SLP132 70008 T10891133 11056 21106 51022 $
     KTTN 131253Z 25006KT 10SM CLR M07/M13 A2994 RMK AO2 SLP137 T10721128 $
     KTTN 131353Z 24007KT 10SM CLR M05/M11 A2996 RMK AO2 SLP141 T10501111
     KTTN 131453Z 26009G15KT 10SM CLR M03/M10 A2996 RMK AO2 SLP140 T10331100 50009
     KTTN 131553Z 27012KT 10SM CLR M02/M09 A2996 RMK AO2 SLP143 T10171089
     KTTN 131653Z 25008KT 10SM CLR 00/M08 A2995 RMK AO2 SLP139 T00001083
     KTTN 131753Z 25011KT 10SM CLR 01/M08 A2992 RMK AO2 SLP128 T00061083 10011 21106 58012
     KTTN 131853Z 26011KT 10SM CLR 01/M08 A2991 RMK AO2 SLP123 T00111083
     KTTN 131953Z AUTO 25011G19KT 10SM CLR 01/M08 A2991 RMK AO2 SLP124 T00111083
     KTTN 132053Z AUTO 24010KT 10SM FEW049 01/M08 A2992 RMK AO2 SLP128 T00111083 55001
     KTTN 132153Z AUTO 24008G17KT 10SM BKN055 01/M08 A2992 RMK AO2 SLP129 T00061083
     KTTN 132253Z AUTO 25008KT 10SM BKN060 01/M08 A2994 RMK AO2 SLP135 T00061083
     KTTN 132353Z AUTO 23004KT 10SM BKN055 M01/M08 A2995 RMK AO2 SLP140 T10061078 10017 21006 53012
     KTTN 140053Z AUTO 21005KT 10SM CLR M02/M08 A2995 RMK AO2 SLP139 T10171083
     KTTN 140153Z AUTO 22005KT 10SM CLR M02/M08 A2996 RMK AO2 SLP142 T10221083
     KTTN 140253Z AUTO 21005KT 10SM CLR M03/M08 A2997 RMK AO2 SLP145 T10281083 53006
     KTTN 140353Z AUTO 20005KT 10SM BKN090 OVC120 M03/M08 A2998 RMK AO2 SLP147 T10281078
     KTTN 140453Z AUTO 19004KT 9SM OVC080 M03/M07 A2998 RMK AO2 SLP148 T10331072 400171106
     KTTN 140553Z AUTO 00000KT 9SM FEW065 SCT095 M04/M07 A2999 RMK AO2 SLP151 T10391067 11006 21044 53006
     KTTN 140653Z AUTO 00000KT 8SM CLR M03/M07 A2999 RMK AO2 SLP152 T10331067

The temperatures reported in the remarks section are as follows (you can figure out the dew points yourself):

-6.7 °C

-9.4 °C

-8.3 °C

-8.9 °C

-8.9 °C

-7.2 °C

-5.0 °C

-3.3 °C

-1.7 °C

+0.0 °C

+6.1 °C

+1.1 °C

+1.1 °C

+1.1 °C

+0.6 °C

+0.6 °C

-0.6 °C

-1.7 °C

-2.2 °C

-2.8 °C

-2.8 °C

-3.3 °C

-3.9 °C

-3.3 °C

So, over that day-long period, the temperatures ranged from -9.4 °C to +6.1 °C.

Yet, only a few different numbers show up.

No matter how long you watch the reports for KTTN, you will never see any of these temperatures in that range: -9.3, -9.2, -9.1, -9.0, -8.8, -8.7, -8.6, -8.5, -8.4, -8.2, -8.1, -8.0, -7.9, -7.7, -7.6, -7.5, -7.4, -7.3, -7.1, -6.9, -6.8, -6.6, -6.5, -6.4, -6.3, -6.2, -6.0, -5.9, -5.8, -5.7, -5.5, -5.4, -5.3, -5.2, -5.1, -4.9, -4.8, -4.7, -4.6, -4.5, -4.3, -4.2, -4.1, -4.0, -3.8, -3.7, -3.6, -3.5, -3.4, -3.2, -3.1, -3.0, -2.9, -2.7, -2.6, -2.5, -2.4, -2.3, -2.1, -2.0, -1.9, -1.8, -1.6, -1.5, -1.4, -1.3, -1.2, -1.0, -0.9, -0.8, -0.7, -0.5, -0.4, -0.3, -0.2, -0.1, 0.1, 0.2, 0.3, 0.4, 0.5, 0.7, 0.8, 0.9, 1.0, 1.2, 1.3, 1.4, 1.5, 1.6, 1.8, 1.9, 2.0, 2.1, 2.3, 2.4, 2.5, 2.6, 2.7, 2.9, 3.0, 3.1, 3.2, 3.4, 3.5, 3.6, 3.7, 3.8, 4.0, 4.1, 4.2, 4.3, 4.5, 4.6, 4.7, 4.8, 4.9, 5.1, 5.2, 5.3, 5.4, 5.5, 5.7, 5.8, 5.9, or 6.0.

Rather, the only numbers you will see in that range are -9.4, -8.9, -8.3, -7.8, -7.2, -6.7, -6.1, -5.6, -5.0, -4.4, -3.9, -3.3, -2.8, -2.2, -1.7, -1.1, -0.6, 0.0, 0.6, 1.1, 1.7, 2.2, 2.8, 3.3, 3.9, 4.4, 5.0, 5.6, and 6.1.

Pretty misleading not to mention that, isn't it? Gene Nygaard 08:16, 14 February 2006 (UTC)

Note that they always jump by 0.5 °C or 0.6°C, skipping all the numbers in between. Gene Nygaard 08:21, 14 February 2006 (UTC)

Yes I know that, that's why I said they reported them accurately to the nearest degree FAHRENHEIT above. Famartin 05:47 15 February 2006 (UTC)

No, they don't "report" anything in degrees Fahrenheit. They misleadingly report in tenths of a degree Celsius. Gene Nygaard 20:34, 19 February 2006 (UTC)

Note that what is actually reported is incorrect, to the stated precision, a whopping 82% of the time, assuming accurate measurements of the temperature. Furthermore, even what is reported in the main body of the METAR (the element containing something along the lines of 06/M02) is incorrect 2 times out of 15—for example, if the actual temperature were 41.72 °F, it gets measured as 42 °F and converted to 6 °C in the main body of the METAR, but actually 41.72 °F = 5.40 °C and should round to 5 °C, if FMH-1 were followed and the readings actually made to the nearest tenth of a degree Celsius. Gene Nygaard 15:10, 20 February 2006 (UTC)

Get over yourself and your ridiculous nitpicking complaints against US METARS. They're done for a reason (preference for Fahrenheit over Celsius, but pressure to report in metric units whenever possible over Imperial units), and if you don't like it, too bad. The explanation that I have in there currently is more than adequate. You're introducing POV into the article. STOP IT! Famartin 05:23, 21 February 2006 (UTC)

--Graphex 20:14, 27 November 2006 (UTC) Removed erroneous abbreviation (METAR does NOT mean METeorological Aerodrome Report) and added in the original French words from which METAR was derived. Updated definition to FAA standard, "Aviation Routine Weather Report".