When the FAA changed its weather reporting format to match the international metar standard several years ago many of us with more than a few years in the logbook scoffed. For one thing, what was a "metar" anyway? We had grown up, and grown old, with the sequence report that used to clatter out of old low-speed teletype machines at flight service stations spread across the country. The word "sequence" made sense because it was a sequential observation of the weather conditions over the airport on the hour, or when rapid changes made a special report useful.
Metar is an acronym of some international terminology having to do with meteorology, I think. I don't really remember. It contained new abbreviations for weather phenomenon such as the letters BR for mist. What's up with BR? Derived from French, I think. And low ceiling heights were replaced with a report of "vertical visibility" in hundreds of feet. We always thought of visibility as a quantity you measured looking straight ahead, not up. If you're looking up instead of ahead when landing, it's not going to work out very well.
But most galling about the metar format was the change in order -- and apparently change in emphasis -- of the observed weather conditions. For many decades American pilots were used to seeing the ceiling and visibility come first in the sequence report. That is what we all talked about, and wanted to know. Two hundred and a half was the sequence report that separated the real pilots from others. That meant the ceiling was 200 feet and visibility one half mile, the typical minimums for an ILS approach, and ceiling and visibility always came first in the report.
The international aviation authorities who developed the metar format many years before the FAA adopted it had a different priority -- wind. The first item in a metar, after the airport identifier, is wind direction and velocity. If it is gusting, that value is reported after the speed of the steady state wind. And if the wind is variable in direction, the range of variation in degrees is also reported. Clearly wind is a big deal in the metar.
In the old sequence report, wind got the ranking it deserved; at least pilots at the time thought so. We worried most about ceiling and visibility and that was first, followed by the reason for any visibility restriction such as haze, fog, rain, snow, dust, smoke and so on. After that in the sequence report came the atmospheric pressure in millibars, information of little use to most pilots in the U.S. with altimeters that could only accept barometric pressure in inches of mercury (hg). Next was the temperature and dew point, and it was in degrees F. Temperature aloft forecasts were in C, but on the surface in the sequence report the temperature was in Fahrenheit so we didn't need to translate to guess how comfortable we would be after landing. Mostly we worried about the spread between the temp and dew point because a small spread is a good indicator of the likelihood of fog forming.
Finally, after all of that came the wind direction and speed in the sequence report. The only thing less important than the wind was apparently the altimeter setting -- that was abbreviated so you needed to translate -- and remarks, if there were any from the observer. Wind was bringing up the rear in the worries of pilots who relied on the sequence report for all of those years.
But, looking back, I have to admit those international types who created the metar got it right. Wind belongs at the front, and should be foremost in a pilot's thinking and planning when considering takeoff or landing. Yes, you need enough ceiling and visibility to see the runway to land, but it is wind that will have the final say on how that landing works out.
I started thinking about all this while reading a metar on a particularly breezy day shortly after reviewing a bunch of preliminary accident reports. Without question the most common accident scenario for all airplane types involves running off the end of, or side of, or hitting short of, the runway. Often these accidents bruise only the pilot's ego and bend his airplane, but there are also many disasters, particularly in larger and heavier airplanes. And in many of these accidents strong and gusting winds are an important factor.
