Wx Watch: METARs and TAFs Ahead

I have good news and bad news. First, the bad. METARs and TAFs are going to become a fact of life, and the switch to these new weather reporting formats will still take place next year. Soon, there'll be no more hourly surface observations reported in the kind of weather abbreviations we've all come to know. Instead, METARs (meteorological reports — aviation routine) will be the rule. We'll all have to learn a new set of weather codes and abbreviations.

Same thing with terminal forecasts and their traditional jargon. They'll be replaced by TAFs (terminal aerodrome forecasts) and a whole new forecast language. All of this is being done in the name of world standardization, under terms of a set of agreements made by the World Meteorological Organization and the International Civil Aviation Organization, branches of the United Nations.

Now the good news. The implementation date for METARs and TAFs has slipped. The original plan was to make the big switch on January 1, 1996. Now, I'm told that D-Day has been moved to June 1, 1996. Turns out that the conversion is a monumental job, and governmental agencies have found the task more arduous than originally anticipated.

"It looks like June 1 will be the latest date [for implementation]," says Rich Heuwinkel, the Federal Aviation Administration's Aviation Weather Division manager. "We may beat the June 1 date by a month or two. It depends on how the internal tests work out."

This six-month slippage gives us a little more time to learn the new formats and codes. We last discussed METARs and TAFs in " Wx Watch" in the September 1993 issue of AOPA Pilot. For those of you who save your back issues, now would be a great time to review that article, which was titled "A Change in the Weather."

You might also consider purchasing an educational videotape coproduced by the FAA and the AOPA Air Safety Foundation. Titled Introduction to METAR/TAF, the tape leads viewers through sample observations and forecasts and would be a worthwhile addition to every pilot's library. Flight instructors will find the tape invaluable as a teaching aid. To order a copy, call the ASF at 800/638-3101. The price is $10 per copy, plus $3.25 shipping and handling.

For a quick refresher, check out the decoding charts published with this article. I want to stress that the information on these charts is subject to change. This draft information is provided courtesy of Howard Diamond, a program manager in the National Weather Service's Office of Systems Operations. He's been the NWS's point man in the METAR/TAF conversion effort.

The shaded blocks of information indicate the changes made to the METAR and TAF codes as of July 12, 1995. You'll see, for example, that a provision for identification of automated surface observations — AUTO — has been added. FEW, a term indicating 1/8 to 2/8 sky coverage, has also been added in the latest round of revisions to the TAF code.

Other late-breaking changes are in the works. The terms COR (a corrected observation) and SPECI (a special observation) will probably be added at the head of the METARS requiring them. Also, some language defining wind shear should also be added to the final set of METAR and TAF weather codes.

Once again, the information on the cards reproduced here is not final. We publish them for educational purposes only, to help facilitate what everybody hopes will be a massive and successful learning experience. Final versions of the cards will be distributed en masse by the NWS and the FAA as soon as everything is complete.

The production of the cards is but a tiny part of the conversion effort. The lion's share of the job involves reconfiguring 17 different communications systems; reprogramming ASOS stations so that their voice messages are in METAR-speak (latest word is that AWOS broadcasts will retain the old codes and format for the time being, then have a gradual phase-in to METAR); changing various publications; and altering texts, manuals, and tests.

The educational effort is also quite immense. It's not just pilots who have to learn the new codes, but controllers, meteorologists, flight service specialists, airline dispatchers, contract observers, and many others.

The conversion to METARs and TAFs has created no small amount of confusion, and even a little bit of outright anger. Why can't the rest of the world conform to American standards, critics ask. Isn't English the worldwide language of aviation? If so, why are we learning that FU (from the French 'fumé') means smoke, that BR (from the French 'brouillard') means mist, that MI (from the French 'mince') means shallow, or that GR (from the German 'Graupel') means hail?

Yes, English is still spoken in cockpits, towers, and ATC facilities around the world. But outside the United States, METARs and TAFs have been the norm for decades. The rest of the world gave up their native languages as the price of admission to the world aviation community, so it is now our turn to give a little bit.

At least, that's how I try to rationalize METARs and TAFs in my calmer moods. Sometimes it works, sometimes it doesn't.

How will the changeover affect you? It depends. If you're a flight instructor, you'd better start boning up right now. If you fly internationally, you'll begin seeing METARs for all U.S. destinations — and TAFs for some 80 American airports — beginning January 1, 1996. You'll see them overseas as you call up American weather.

On or about June 1, pilots flying domestically can say goodbye to SAs and FTs forever.

There is an up side. Translation into plain English will be available for DUATS briefings and for subscribers to private vendors of weather information. Also, METAR- and TAF-speak shouldn't impair in-flight or in-person communications with flight service or flight watch briefers. Together, we'll no doubt muddle through the transition period.

Our work is cut out for us. METARs and TAFs will take time to master. On top of that, these reports give us more — and more detailed — information than we ever dealt with in the old SAs and FTs. This means that we really have two missions ahead of us — learning the codes and learning how to interpret the higher volume of data. The latter may be the biggest hurdle of all.

We'll certainly keep you posted as this saga continues to unfold.

METAR/TAF Self Quiz

METAR

1. KPHL 1550Z 24007KT 7SM BKN009 OVC020 18/16/ A3005
2. KLAX 1550Z 21008KT 1/2SM R14/3500V5500FT FG OVC003 14/14 A3018
3. KACY 1545Z 00000KT 11/4SM -SHSN BKN006 OVC010 M03/M03 A2942 RMK SB30
4. KBUF 1549Z 35015G27KT 1/4SM BLSN R31/1200FT VV003 01/MO1 A3013
5. KBOS 1549Z 15012KT 6SM -RASN SCT004 BKN009 OVC015 02/MO1 A2949 RMK PRESFR
6. KBWI 1550Z 09008KT 3/4 SM R10/3800FT -FZDZ PE 008OVC M01/M01 A2990

TAF

KJKF 251720Z 1818 21007KT 5SM-SHRA BKN030 OVC080
FM 22Z 33015G25KT P6SM BKN030 BKN080 PROB40 2301 1SM TSRA
FM05 32005 P6SM 050SCT 100SCT TEMPO 0709 00000KT 1SM FG
FM12 33010 4SM FGHZ BECMG 1416 30010 P6SM NSW SKC

METAR/TAF Quiz Answers

METAR

1. KPHL 1550Z 24007KT 7SM BKN009 OVC020 18/16 A3005 PHILADELPHIA, PA 1550Z OBSERVATION, WINDS 240 DEGREES AT 7 KNOTS, VISIBILITY 7 STATUTE MILES, THE CEILING IS 900 BROKEN WITH AN OVERCAST CLOUD DECK AT 2000 FEET, TEMPERATURE 18 DEGREES CENTIGRADE, DEW POINT 16 DEGREES CENTIGRADE, ALTIMETER 30.05.
2. KLAX 1550Z 21008KT 1/2SM R14/3500V5500FT FG OVC003 14/14 A3018
   LOS ANGELES, CA 1550Z OBSERVATION, WINDS 210 DEGREES AT 8 KNOTS, VISIBILITY 1/2 MILE STATUTE, RUNWAY 14 RUNWAY VISUAL RANGE (RVR) IS 3500FT VARIABLE TO 5500FT IN FOG, THE CEILING IS 300 FT OVERCAST, TEMPERATURE 14 DEGREES CENTIGRADE, DEW POINT 14 DEGREES CENTIGRADE, ALTIMETER 30.18.
3. KACY 1545Z 00000KT 11/4SM -SHSN BKN006 OVC010 M03/M03 A2942 RMK SB30
   ATLANTIC CITY, NJ 1545Z OBSERVATION, WINDS CALM, VISIBILITY 1 1/4 STATUTE MILES IN LIGHT SNOW SHOWERS, THE CEILING IS 600 FEET BROKEN WITH AN OVERCAST CLOUD DECK AT 1000 FEET, TEMPERATURE IS MINUS 3 DEGREES CENTIGRADE, DEW POINT IS MINUS 3 DEGREES CENTIGRADE, THE ALTIMETER IS 29.42, AND REMARKS INDICATE THAT THE SNOW BEGAN FALLING AT 1530Z.
4. BUF 1549Z 35015G27KT 1/4SM BLSN R31/1200FT VV003 01/M01 A3013
   BUFFALO, NY 1549Z OBSERVATION, WINDS ARE 350 DEGREES AT 15 KNOTS GUSTING TO 27 KNOTS WITH 1/4 MILE (STATUTE) VISIBLITY IN BLOWING SNOW, RUNWAY 31 RUNWAY VISUAL RANGE (RVR) IS ONLY 1200 FEET, AND THE CEILING IS INDEFINITE 300 FEET, TEMPERATURE IS 1 DEGREE CENTIGRADE, DEW POINT IS MINUS 1 DEGREE CENTIGRADE, AND THE ALTIMETER IS 30.13.
5. KBOS 1549Z 15012KT 6SM -RASN SCT004 BKN009 OVC015 02/M01 A2949 RMK PRESFR
   BOSTON, MASS 1549Z OBSERVATION, WINDS FROM 150 DEGREES AT 12 KNOTS, VISIBILITY 6 STATUTE MILES IN MIXED LIGHT RAIN AND SNOW, SCATTERED CLOUDS AT 400 FEET, A BROKEN CEILING AT 900 FEET AND AN OVERCAST DECK AT 1500 FEET, TEMPERATURE IS 2 DEGREES CENTIGRADE, DEW POINT IS MINUS 1 DEGREE CENTIGRADE, THE ALTIMETER IS 29.49 AND REMARKS INDICATE THAT THE PRESSURE IS FALLING RAPIDLY.
6. KBWI 1550Z 09008KT 3/4SM R10/3800FT-FZDZ PE 008OVC M01/M01 A2990
   BALTIMORE, MD 1550Z OBSERVATION, WINDS DIRECTLY OUT OF THE EAST (090 DEGREES) AT 8 KNOTS, WITH ONLY 3/4 STATUTE MILE VISIBILITY, RUNWAY 10 HAS A RUNWAY RANGE (RVR) OF ONLY 3800 FEET IN LIGHT FREEZING DRIZZLE AND ICE PELLETS, WITH A CEILING OF ONLY 800 FEET, TEMPERATURE IS MINUS 1 DEGREE CENTIGRADE, A DEW POINT OF MINUS 1 DEGREE CENTIGRADE, AND THE ALTIMETER IS 29.90.

TAF

KJKF 251720Z 1818 21007KT 5SM -SHRA BKN030 OVC080
FM 22Z 33015G25KT P6SM 030BKN BN080 PROB40 2301 1SM

TSRA
FM05 32005 P6SM 050SCT 100SCT TEMPO 0709 00000KT 1SM

FG
FM12 33010 4SM FGHZ BECMG 1416 30010 P6SM NSW SKC

THIS IS THE TERMINAL FORECAST FOR JOHN F. KENNEDY AIRPORT FOR THE 25TH DAY OF THE MONTH, PREPARED AT 1720Z, FOR THE PERIOD FROM 1800Z OF THE 25TH UNTIL 1800Z ON THE 26TH. THE TAF CALLS FOR, FROM THE BEGINNING OF THE FORECAST PERIOD (1800Z) UNTIL 2200Z, WINDS OUT OF THE SOUTHWEST AT 7 KNOTS, WITH THE VISIBILITY TO BE 5 STATUTE MILES IN LIGHT RAIN SHOWERS, WITH A CEILING OF 3000 FEET AND AN OVERCAST DECK AT 8000 FEET. AFTER 2200Z, IT CALLS FOR WINDS OUT OF THE NORTHWEST (NOTICE THE WIND SHIFT) AT 15 TO 25 KNOTS, WITH VISIBILITY IMPROVING TO MORE THAN 6 STATUTE MILES WITH JUST BROKEN CLOUDS, ONE DECK AT 3000 FEET AND THE OTHER AT 8000 FEET WITH A PROBABILITY OF (OCCASIONALLY), BETWEEN 2300Z AND 0100Z, VISIBILITY DROPPING TO 1 STATUTE MILE IN THUNDERSTORMS AND RAIN SHOWERS. AFTER 0500Z, THE WINDS ARE EXPECTED TO BE OUT OF THE NORTHWEST AT ONLY 5 KNOTS, VISIBILITY MORE THAN 6 STATUTE MILES WITH JUST SCATTERED CLOUDS AT 5000 AND 10,000 FEET, BUT TEMPORARILY (CHANCE OF), BETWEEN 0700Z AND 0900Z, THE WINDS BECOMING CALM AND VISIBILITY DROPPING TO 1 STATUTE MILE IN FOG. AFTER 1200Z, THE FORECAST CALLS FOR WINDS OUT OF THE NORTHWEST AT 10 KNOTS WITH VISIBILITY 4 STATUTE MILES IN FOG AND HAZE BECOMING BETWEEN (OR BY) 1400-1600Z, WINDS OUT OF THE NORTHWEST AT 10 KNOTS, VISIBILITY MORE THAN 6 STATUTE MILES WITH NO SIGNIFICANT WEATHER AND CLEAR SKIES.