Wx Watch: The METAR/TAF Takeoff

Every once in a while I'm lucky enough to have the chance to ferry airplanes to and from Europe — and sometimes beyond. So believe me when I say that operating in foreign airspace can provide plenty of challenges and concerns. One of them is deciphering foreign weather reporting formats and abbreviations. All of the nations in the world- -save the United States and Canada — use International Civil Aviation Organization (ICAO) weather formats and codes. These include METARs and TAFs, the ICAO equivalent of our SAs (hourly surface observations) and FTs (terminal forecasts), respectively.

So there I was last February in Guernsey, a small British island off France's Normandy coast, poring over the weather information for Malta's Luqa Airport — my next destination. It's about 0700Z, and the flight should take approximately eight hours. And, yes, there's more than enough fuel on board my airplane, thanks to an extra 100 gallons loaded in the ferry tanks. I'm looking at a TAF that says (pay attention, a quiz follows):

LMML 040500Z 040615 13007KT 0600 FG SCT004 TEMPO 0607 0100 BECMG 0709 3000 BR SCT010 BECMG 0911 9000 SCT012 BKN100 PROB30 TEMPO 1315 5000 RA BKN005 OVC080.

Not great weather, but not bad, either. At least I could read the forecast without any trouble — something I couldn't say 10 years ago when I began ferrying, and well before the newest TAF codes came into being. Back then, only ferry pilots and crews of international airline and military flights had any need to know METARs and TAFs. Now, we all do.

By now, most pilots here in the United States should have learned that METARs and TAFs are coming to these shores and that SAs and FTs are on the way out. The latest proclamation from the National Weather Service (NWS) indicates that these major switches in our weather formats will take place on July 1, 1996, at precisely 0800 Zulu time. No more delays, the NWS and FAA swear.

After July 1 — assuming that the FAA can put the plan into action on a timely basis — pilots scanning printouts at flight service stations will see a whole new world of abbreviations and reporting sequences. Those tuning in to ASOS, AWOS, and ATIS broadcasts will hear the first recorded METAR reports.

In case you've been napping, METAR stands for aviation routine meterological report and TAF is the abbreviation for terminal aerodrome forecast. METARs will supplant SAs; TAFs will take the place of FTs. It's all part of a scheme to set a worldwide standard for all aviation weather reporting, and it comes to us via ICAO, a branch of the United Nations.

Over the past year or so, AOPA and AOPA Pilot have received plenty of mail and telephone calls from members angry about the change to these new reports. Because I've written about the METAR/ TAF conversion in past issues (see "Wx Watch: A Change in the Weather," September 1993 Pilot, and "Wx Watch: METARs and TAFs Ahead," September 1995 Pilot), I'm considered by some around the building as the resident expert on the subject, so I get my share of calls.

The complaints seem to run along the same lines. English is the international language of aviation, so why adopt abbreviations of French origin? The United Nations is trampling all over our sovereignty by jamming these new codes down our throat, so why cave in? Then there's the big complaint — that AOPA dropped the ball on the issue. The fact is that AOPA fought the good fight against the ICAO proponents but lost. Tom Haines, AOPA Pilot's editor-in-chief, explained the atmosphere surrounding the issue very well recently (see "Waypoints: And now the news...," March Pilot), so I feel no need to open this subject once again.

Instead, I bring two messages. One is of trust and confidence. Trust that all will work out well in the end. Trust that pilots and flight instructors will be diligent in learning and teaching the new codes and formats. Trust that the Federal Aviation Adminstration will do the same for its personnel and programs affected by the change. Confidence in our ability as well-informed, high-achieving individuals to master the new jargon.

The other message is a bit sterner. To all fellow American pilots out there, I say, "Get over it."

I know that this kind of bluntness all but ensures my receiving yet another round of feisty mail and hot phone calls. But what can I say? The rules will go into effect — if not on July 1, then some day soon afterward. We'll all have to learn them. We'll all have to use them. It's not the end of the world. The sun will come up again tomorrow, and we'll still fly.

It shouldn't be that bad, actually. Flight service briefers will still give you briefings in plain English and answer any questions you may have about the new abbreviations and formats. DUATS providers will give you a choice — METARs and TAFs in straight code or plain English. The plain English versions will present their information in the same sequence as the straight code format, but will include translations of all the foreign-origin abbreviations.

This means that there will be plenty of opportunites for on- the-job training. Each time you receive an FSS or DUAT briefing or obtain a weather update on flight watch (122.0 MHz), you'll have the chance to ingrain a little bit more of the new codes and formats.

About the only times you'll come across unvarnished METAR- and TAF-speak would be when reading straight-code DUATS, untranslated FSS reports and forecasts during an in-person briefing at a flight service station, or when listening to METARs on AWOS, ASOS, or ATIS broadcasts.

Now for some news. At least it was news to me, and as far as I know there has been very little official publicity about yet another aspect of the switch to the ICAO codes. The abbreviations used in METARs and TAFs will also appear in area forecasts (FAs), airmets, sigmets, pireps, TWEB forecasts, and Center Weather Advisories.

There won't be a shortage of learning aids to help us through the change. The FAA will send to you, free, one or more training booklets. Just call 202/267-7770 and leave your request on the voice mail. You want the booklet called New Aviation Weather Formats: METAR/TAF, or publication ASY-20.

AOPA is working on a free pocket-sized translation card.

The AOPA Air Safety Foundation has developed an educational videotape on METARs and TAFs. It's available for $13.25. Contact the Foundation at 800/638-3101, and have your Visa or MasterCard at the ready.

Video educators John and Martha King of King Schools tell me that they'll be offering a tape on METARs and TAFs. The tape's duration should be one hour, 15 minutes, and the price is now set at $29. Sporty's Pilot Shop and Jeppesen also have educational tapes in the works.

The NWS has set up a home page on the World Wide Web. Here you can access and download the latest developments in the METAR/TAF saga, training guides, test data, and much more. The address is: www.nws.noaa.gov/oso/oso1/oso12/metar.htm.

If the move to METARs and TAFs has you fuming, just remember two other recent major conversions. In 1975, many pilots went into a rage when our aircraft performance specifications and navigation formulas were switched from statute to nautical miles. In 1993, an airspace reclassification — again, to bring our airspace nomenclature in line with the rest of the world's — came about despite howls of protest. Today, having fully assimilated the changes, we wonder what all the fuss was about.

So it will be with METAR/TAF. I'll make a prediction that the switch to the ICAO format will be a smooth one. After a month or two of working out the kinks, we'll all be conversant in the new lingo. That's what happens when you're staring at a TAF and you have to make a go/no-go decision. The learning incentive skyrockets when you're faced with real-world operational decisions involving new sets of information.

Which brings us back to Guernsey — and the quiz. Please answer the following questions about the weather report:

1. What's the date of the flight?
2. When was the TAF issued?
3. What are the valid times for the TAF?
4. What is the forecast surface wind and visibility at Malta for 0600Z?
5. What does "0600 FG" mean?
6. What does "SCT004" mean?
7. What temporary change can we expect between 0600Z and 0700Z?
8. Translate "BECMG 0709 3000 BR SCT010."
9. What is the weather forecast to become between 0900Z and 1100Z?
10. What does "PROB30" mean?
11. What will the weather be at the ETA?
12. This TAF uses one type of code and two format elements that won't be used in U.S. forecasts. What are they?
13. Provide the entire translation.
14. Extra credit: The next day, my TAF read: HELX 050400Z 05 0615 28015KT CAVOK. Where was I going, and what was the forecast?

Answers:

1. The fourth of February
2. 0500Z
3. From 0600Z to 1500Z
4. 130 degrees true at 7 knots, visibility 600 meters in fog
5. 600-meter visibility in fog
6. A scattered layer of clouds at 400 feet agl is predicted.
7. 100-meter visibility
8. "Becoming from 0700Z to 0900Z, visibility 3,000 meters in mist, 1,000 feet scattered."
9. Visibility 9,000 meters, 1,200 feet scattered, 10,000 feet broken
10. A 30-percent probability
11. A 30-percent probability of temporary 5,000-meter visibility in rain, with a broken layer at 500 feet, and an overcast at 8,000 feet
12. a) The visibility values are given in meters. In the United States, statute miles and fractions of statute miles will be used.
    b) European TAFs use forecast periods valid for 9 hours. In the United States, 24-hour forecast validity periods will be used.
    c) The "PROB30 TEMPO" code will not be used in the United States. Instead, only the term "PROB30" will be used. The reasoning is that a 30-percent chance of an event's happening, by itself, indicates the likelihood of a temporary condition.
13. TAF for Malta/Luqa issued on the fourth day of the month at 0500Z effective from the fourth day of the month at 0600Z until 1500Z on the fourth. Initial prevailing conditions call for winds from 130 degrees at 7 knots, visibility 600 meters with fog, and a scattered layer at 400 feet. Temporarily, from 0600Z to 0700Z, the visibility will decrease to 100 meters. From 0700Z to 0900Z there will be another change to a new set of prevailing conditions, with an increase in the visibility to 9,000 meters, with a scattered layer at 1,200 feet and a broken layer at 10,000 feet. There is a 30- percent probability that a temporary change will occur between 1300Z and 1500Z, when the visibility may decrease to 5,000 meters with moderate rain and a broken layer at 500 feet and an overcast layer at 8,000 feet.
14. TAF for Luxor, Egypt, issued on the fifth day of the month at 0400Z. For the fifth day between 0600Z and 1500Z winds are forecast to be 280 degrees at 15 knots. Visibilities 10 kilometers or better; no clouds below 5,000 feet, no cumulonimbus; and no precipitation, thunderstorms, sandstorms, duststorms, fog, or snow. CAVOK, which implies all the conditions in the last sentence, will not be used in U.S. TAFs.

METAR/TAF Trivia

Q: How much cloud coverage does a SCT layer have?
A: 3/8 to 4/8 of the sky.

Q: What about a BKN layer?
A: 5/8 to 7/8 sky coverage.

Q: And OVC?
A: You got it. 8/8 coverage.

Q: What's the difference between mist (BR) and fog (FG)?
A: BR is fog with visibilities of 5/8 SM or better. FG means fog with visibilities less than 5/8 SM.

Q: What's VC BLSN mean?
A: Blowing snow is in the vicinity of the airport (between five and 10 statute miles from the point of observation).