The most important factor in determining which runway to use for takeoff or landing is arguably the weather. Whether you are on VATSIM, PE or offline (pun intended) you cab obtain current and forecasted weather reports with a METAR. This Class will help you decode a METAR and teach you what the abbreviations stand for.
Requesting a METAR
VATSIM
To request a text METAR on VATSIM using XSB, type this in the chat:
.metar CODE where CODE is the ICAO of the airport wanted.
i.e. Juneau, you would type .metar PAJN
X-PLANE
To request a METAR click your map on the airport desired to obtain the radio frequency needed to hear the ATIS and get the latest report.
A Typical Example
Lets examine a METAR for, say, Amsterdam, sexy women and good food! METARs right, sorry!
Keep in mind over in Europe they use meters instead of miles.
EHAM 291050Z 24015KT 9000 RA SCT025 BKN040 10/09 Q1010 NOSIG
Decoded: METAR for Amsterdam Schiphol dated the 29th at 10h50z; wind direction is at 240 degrees and 15 knots; 9000 meters visibility; Rain, scattered cloud at 2500 feet; broken cloud at 4000 feet; Temperature is 10 degrees; dew point is 9 degrees; QNH is 1010; No significant change expected in the next few hours.
Decoding Legend
In the example above you get a vague idea of what some parts of a METAR mean, let’s break it down by sections and help you understand further.
EHAM 291050Z 24015KT 9000 RA SCT025 BKN040 10/09 Q1010 NOSIG
The first section always contains the ICAO code for the airport
EHAM 291050Z 24015KT 9000 RA SCT025 BKN040 10/09 Q1010 NOSIG
The second part is the date
EHAM 291050Z 24015KT 9000 RA SCT025 BKN040 10/09 Q1010 NOSIG
After the date is the time of the report, which is always UTC
EHAM 291050Z 24015KT 9000 RA SCT025 BKN040 10/09 Q1010 NOSIG
Then the wind direction in degrees and its speed in knots
EHAM 291050Z 24015KT 9000 RA SCT025 BKN040 10/09 Q1010 NOSIG
Visibility in meters (for Europe, miles are used elsewhere)
EHAM 291050Z 24015KT 9000 RA SCT025 BKN040 10/09 Q1010 NOSIG
RA means there is rain
EHAM 291050Z 24015KT 9000 RA SCT025 BKN040 10/09 Q1010 NOSIG
SCT means there are scattered clouds
025 means they are at 2500 feet
EHAM 291050Z 24015KT 9000 RA SCT025 BKN040 10/09 Q1010 NOSIG
BKN means there are broken clouds
040 means they are at 4000 feet
EHAM 291050Z 24015KT 9000 RA SCT025 BKN040 10/09 Q1010 NOSIG
In this section the temperature is always first, followed by the dew point so:
- The temperature is 10 degrees
- The dew point is 9 degrees
EHAM 291050Z 24015KT 9000 RA SCT025 BKN040 10/09 Q1010 NOSIG
When you see NOSIG at the end of a METAR this means that no significant changes are expected in the next few hours
Decoders
There are some free tools online which allow you to decode METARs easily and I recommend their use to learn what all the abbreviations and terms within them mean.
http://heras-gilsanz.com/manuel/METAR-Decoder.html
http://www.iflightplanner.com/Resources/MetarTafTranslator.aspx
http://www.metarreader.com/