Section 4 - Chapter 5 - Meteorological Information

Question 1

What meteorological information is supplied to Area Control Centres (ACCs) and how is it categorized?

Answer 1

• Routine Reports: For main and alternate aerodromes within the FIR and adjacent FIRs.
• Trend Forecasts: For main and alternate aerodromes within the FIR.
• Forecast of Conditions in the FIR: Met forms 214/215 or AIRMET Regional/Area Forecasts.
• Aerodrome Forecasts: Met forms 214/215 or AIRMET Regional/Area Forecasts.
• SIGMET Messages: Met forms 214/215 or AIRMET Regional/Area Forecasts, also broadcast on SHANNON HF VOLMET.
• Forecast Regional Pressure Setting Values: For all altimeter setting regions within or partly within the FIR.
• Runway Visual Range: Directly from each aerodrome.
• Advice on Diversions: Provided when requested.

Question 2

How do ACCs obtain and supplement meteorological information for aircraft in flight?

Answer 2

• Primary Source: Most meteorological information is obtained directly from the VOLMET broadcast.
• Supplemental Information: Occasionally supplemented on operational frequencies, especially for SIGMET messages and RVR observations.

Question 3

What are the methods and guidelines for transmitting meteorological information to aircraft in flight?

Answer 3

• Methods of Transmission:
  1. Direct transmission to individual aircraft.
  2. Broadcast on ATC frequencies.
• Conformance: Ensure information transmitted matches the type requested (e.g., report vs. forecast).
• SIGMET Messages: Relay with minimal delay to all affected aircraft, without compromising flight control.
• RVR Values: Transmit when requested by pilots or at controller’s discretion.
• Source of Information: Generally, only transmit meteorological information supplied or agreed by the Meteorological Office, with exceptions detailed in Section 3, Chapter 1.