MANAIR Manual of Standards and Procedures for Aviation Forecasts: introduction

1.1 Purpose of manual

This manual is incorporated as a regulatory standard by reference from Canadian Aviation Regulations (CAR) 804.01(1)(b). It specifies procedures, practices and formats to be used in the preparation of aviation weather forecasts in Canada. It expands upon the International Standards and Recommended Practices as stated in the International Civil Aviation Organization (ICAO) Annex 3 to the Convention on International Civil Aviation - Meteorological Service to International Air Navigation as referenced by CAR 804.01(1)(a). The standards in Annex 3 are superseded, domestically, by State differences filed by Canada against the Annex in accordance with CAR 800.01(2). The standards in this manual have equal weight with the standards in Annex 3 or those formed by Canadian State differences to the Annex but they take precedence over recommended procedures established in Annex 3.

1.2 Word meaning

The bolded word "shall" is used in this manual to indicate that instructions are mandatory, or must be followed. The word "should" is used to denote a recommended practice, or a good way to do something.

1.3 Applicability

This manual has been produced in conjunction with Transport Canada (TC), NAV CANADA, and the Department of National Defence (DND) and shall be used by people involved in the production and delivery of aviation weather forecasts serving all categories of aviation: civil or military, domestic, trans-border (Canada-United States) or international.

1.4 Responsibility for the aviation weather program

The Minister of Transport is responsible for the development and regulation of civil aeronautics and the supervision of all matters connected with civil aeronautics. The responsibility for the provision of civil aviation weather services in Canadian airspace and any other airspace in respect of which Canada has the responsibility for the provision of air traffic control services, has been designated to NAV CANADA. NAV CANADA also specifies the location and frequency of aviation weather observations and forecasts, and is responsible for the dissemination of this information for aviation purposes.

Note: In special circumstances, the Minister of Transport may authorize a private company to issue aviation weather forecasts for specific aerodromes.

The Minister of National Defence is responsible for the development and regulation of military aeronautics and the supervision of all matters connected with military aeronautics. The responsibility for the provision of military aviation weather services in Canada rests with the Director, Meteorology and Oceanography (DMetOc).

Note: Specific exemptions may be authorized by DMetOc in special circumstances when it is essential to conform to the standards or procedures of DND or an allied command (e.g NORAD or NATO).

The International Civil Aviation Organization (ICAO) has designed the World Area Forecast System (WAFS) to provide forecasts of enroute meteorological conditions of the greatest possible accuracy and in a standardized form for international civil flight operations.

In accordance with the standards set by the World Meteorological Organization (WMO) and ICAO, aviation weather forecasts provided by the Meteorological Service of Canada (MSC) are prepared by certified aeronautical meteorological forecasters as defined in 1.6.

1.5 Aviation weather forecast production

Aviation weather forecasts are produced by:

Environment Canada (EC):

  • Environment Canada, MSC has been contracted, by NAV CANADA, the responsibility for the production of civil aviation weather forecasts.
  • EC/MSC, under the provisions of a Memorandum of Understanding with DND, provides similar services.

Private meteorological suppliers:

  • Any private company authorized by TC or DND to issue aviation forecast for specific aerodromes.

1.6 Aeronautical Meteorological Forecaster (AMF)

An Aeronautical Meteorological Forecaster (AMF) is a meteorologist who meets, at a minimum, the definition and top-level competency standards as defined in the Manual on the Implementation of Education and Training Standards in Meteorology and Hydrology, Volume I, Meteorology (WMO-No. 1083), as they pertain to aeronautical meteorology, and who is continuously and actively responsible for the content of any aviation weather forecast service. Additional AMF competencies may be required by the service provider, which are in keeping with Canadian regulations.

1.7 Form of forecasts

Forecasts are issued in one of two forms designed to satisfy internationally agreed upon requirements. The designated formats are identified below.

1.7.1 Chart / graphical

Forecasts in chart or graphical form depict forecast conditions over large areas with greater clarity than forecasts in alphanumerical form. Specifications of this form are given in chapters 4 and 7.

1.7.2 Alphanumeric code

Forecasts in alphanumeric code are used when required by international standards (e.g. aerodrome forecasts in TAF code) or when chart forms are unsuitable.

1.8 Components and types of routine aviation forecasts

Because of differing requirements for detail and accuracy, aviation forecasts are separated into forecasts of aerodrome conditions and forecasts of enroute conditions. Each of these forecasts may be issued in one or more of the forms detailed in 1.7.

1.8.1 Aerodrome forecasts

These are normally issued for periods of 12, 24 or 30 hours at regular intervals (normally every six hours). These forecasts are issued for specified aerodromes in alphanumeric code (TAF).

1.8.2 Forecasts of enroute weather

Forecasts of enroute weather shall be issued, as described:

  • Graphic Area Forecasts (GFA): For aircraft operating over short or medium ranges (less than 1,000 nautical miles) and at altitudes below 24,000 feet, area forecasts are issued at regular intervals (normally every six hours). Detailed specifications of GFA are given in Chapter 4.
  • Significant weather forecasts: For planning operations of aircraft over longer ranges and at altitudes between 700 hPa and 400 hPa (10,000 feet to 24,000 feet), routine forecasts of weather of significance to such operations are produced in chart form as described in Chapter 7.
  • SIGMET: Information message to advise pilots of the occurrence or expected occurrence of specified weather phenomena, which may affect the safety of aircraft operations, and the development of those phenomena in time and space. Details of specifications of SIGMET are given in Chapter 5.
  • AIRMET: Information message to advise pilots of the occurrence or expected occurrence of specified weather phenomena which may affect the safety of aircraft operations, which were not already included in the GFA, and the development of those phenomena in time and space. Details of specifications of AIRMET are given in Chapter 6.
  • Upper Winds and Temperatures (FB): Forecasts in digital of wind and temperatures aloft are produced at six-hour intervals in numerical form for levels below 24,000 feet. Details of FB specifications are provided in Chapter 3.
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