I'm learning to fly airplanes. Weather is important. Pilots get weather reports as METARs and TAFs. Which are inscrutible at first blush, but remarkably concise and efficient once you learn it.

You can get a sense for how inscrutible the language is when you learn that METAR officially stands for "aviation routine weather report". The actual reports are no better.

KSQL 081950Z 35006KT 20SM SCT100 16/05 A3008
KPAO 081947Z 34010KT 30SM SCT150 A3007
KHAF 081955Z AUTO 32007KT 5SM HZ CLR 17/07 A3006
KSFO 081956Z 04004KT 10SM FEW100 SCT180 17/08 A3007 RMK AO2 SLP182 T01670083
That wodge of text is current weather at four airports in the Bay Area. The first line is San Carlos, where the wind is from the north at 6 knots, visibility is 20 miles, cloud cover is scattered at 10,000 feet, and it's 16°C (dewpoint 5°C). That report is pretty simple; it gets more complex when you have codes for thunderstorms, fog, volcanic ash, etc. Charmingly some of the codes are English (TS: thunderstorm) and some are French (GR: grêle, hail).

On first and second exposure I was horrified at this coding. It felt like a 1940s telegram. But having spent a couple of hours studying it I can appreciate its brevity. One particularly nice feature is that it's (more or less) fixed width, so you can quickly vertically compare reports over time or from multiple airports. They're also ideally suited for Twitter: @KSQL, @KPAO.

The METAR websites offer a "translated view", with the data all unpacked into multi-line English. I see now why the pilots I know don't use it; too wordy, and you know the compact format already why not use it? I still think you could make a better reporting system using simple HTML tables, but aviation is conservative. mobilemetar.com strikes a nice balance for iPhone users.

I'm toying with writing blog entries about the pilot learning process, maybe even a separate pilot blog. Or maybe just mix them in here. Have an opinion? Mail me.

  2009-11-08 20:14 Z