Met Documentation and Briefing

Meteorology · Chapter 28 · DGCA CPL and ATPL

What the met office gives you before you fly, how it decides what goes in your folder, and how heights are written on it.

Remember

AMOs supply operators, crews (before departure) and aircraft in flight: winds aloft, reports, forecasts, SIGWX charts, imagery.
Briefing 3 h before departure. Short notice (AMO 3 h, AMS 12 h in this chapter) → oral briefing in the Briefing Register.
Low level/VFR: to FL100 (FL150+ in mountains); visibility ≤ 5000 m; SIGMET for all levels.
T-3 tabular ≤ 500 NM; T-4 cross-section > 500 NM. International: WAFC SIGWX FL250-630 + 250 hPa chart. National: national SIGWX + WAFC winds; low level 600/1500/3000 m.
National SIGWX: MWOs → Chennai; medium FL100-250 (with 0 °C level), high FL250-630; 4 a day, issued 9 h after data, valid 24 h. Heights: en route FL, aerodrome above elevation.

What met information does the AMO give, and to whom?

Who gets what

Who the airport met office serves, how, and with what. Tap Next.

Three kinds of user The aerodrome met office (AMO) serves three kinds of user. Operators get it for planning before the flight, during it, and when they re-plan in flight. Flight crews get it before departure. Aircraft already in the air get it by radio.
In what form The information comes as printed papers, digital data, a briefing, consultation, or a display. A briefing is the forecaster talking you through the weather on your route. Consultation means you can ask questions and talk it over. A display is the charts, reports and pictures put up on screens or boards in the briefing room. Printed or digital papers are what you carry on board.
Five kinds of information Winds: upper winds and temperatures, the maximum wind, the jet stream and the tropopause. Reports: METAR, SPECI, TREND, AIREP, SIGMET and volcanic ash. Forecasts: en-route weather, TAF, take-off, wind shear warnings, and local or area forecasts. Charts: SIGWX. Imagery: satellite and ground radar pictures.

Memory hook: Winds · reports · forecasts · charts · imagery.

Takeaway: The aerodrome met office (AMO) serves operators (for planning before and during flight, and re-planning), flight crews before departure, and aircraft in flight. It gives printed documents, digital data, briefings, consultation and displays. The information is of five kinds: winds aloft, reports, forecasts, SIGWX charts and satellite or radar pictures.

When are you briefed, and what if you gave too little notice?

Briefing rules

When you are briefed, what happens with short notice, and what a low-level flight gets. Tap Next.

Three hours before The briefing tells you the weather now and the forecast at the departure airport, along the route, at the destination and at the alternates. It is given in person to the crew or operations staff 3 hours before the planned departure. If that is not practical, it is given by phone or another link.
Oral briefing The met office needs notice to prepare your documents: in this chapter 3 h for an AMO and 12 h for an AMS. If you gave less, you get only an oral briefing with the same information. It is written in the Briefing Register ("documentation not provided for want of adequate notice") and the crew signs it. Avoid oral briefings when you can.
Low-level and VFR flights For low-level and VFR flights the briefing goes up to FL100, or FL150 and above over mountains. It stresses visibility of 5000 m or less, anything likely to spread visibility below 5000 m, and cloud that may affect the flight. SIGMETs are briefed to flights at all levels, high or low.

Memory hook: Brief 3 h before. Low level to FL100 (FL150 mountains). Vis ≤ 5000 m.

Takeaway: The briefing covers the actual and forecast weather at departure, en route, at the destination and alternates. It is given in person 3 h before the planned departure, or by phone. If the met office had too little notice (3 h for an AMO, 12 h for an AMS), you get only an oral briefing, written in the Briefing Register. Low-level and VFR briefings go up to FL100 (FL150 over mountains) and stress visibility of 5000 m or less, cloud and SIGMET.