Offshore Physical Environmental Guidelines
4.0 Forecasting

4.0 Forecasting
4.1 Site-Specific Marine Weather and Sea State Forecasting
4.2 Aviation Forecasting
4.3 Ice and Iceberg Forecasting

4.0 Forecasting

Two types of weather forecast services are normally required: site-specific marine forecast services for normal and emergency conditions related to drilling or production operations; and aviation weather forecast services for support flights. In addition, in areas subject to sea ice or iceberg incursion, tactical ice forecasts are also required.

4.1 Site-Specific Marine Weather and Sea State Forecasting

The Operator must arrange for site-specific weather and sea state forecasts in support of its operations.

The Operator should ensure that its Weather Forecasting Contractor is familiar with the requirements for forecast services contained in the Operator's Contingency and Response Plans.

Essential elements of the site-specific forecast service include:

• Forecast issuance at least every 6 hours, or more frequently as required;
• Forecast preparation by a qualified meteorologist who has access to all available and appropriate meteorological and other data should maintain a continuous weather watch;
• Data sources should be sufficiently secure and redundant to enable guaranteed data access at all times;
• A forecast amendment service with defined forecast amendment criteria (threshold values);
• Forecast for each synoptic (i.e. 00, 06, 12, 18 UTC) hour in the forecast period of wind speed and direction, sea state (wave and swell height, period and direction), precipitation, visibility, sky conditions, air temperature, freezing spray and icing conditions (when appropriate); and a synopsis of present weather patterns;
• Forecasts should extend over, at least, a 48-hour period;
• An outlook covering the period from the last valid time of the forecast out to 120 hours should be included and should be more qualitative in content than the forecast;
• If a major departure from the MSC regional forecast appears warranted, the forecaster preparing the site-specific forecast should consult with the appropriate MSC Weather Centre;
• In the case of an emergency, special forecasts tailored to the emergency shall be prepared and updated as required; and,
• An effective data communications system is required to ensure the timely transmission and receipt of environmental data and forecasts.

4.2 Aviation Forecasting

TC requires that graphical area forecasts (GFAs) be available to support aviation services to offshore installations. These forecasts are provided by NAVCAN. Real time aviation observations from offshore installations, prepared according to the standards listed in Section 2.0, are required to support the preparation of GFAs.

The Operator may arrange for the provision of Aerodrome Forecasts (TAFs) from either a government or private forecast provider. These TAFs will be prepared in accordance with standards and procedures defined in MANAIR. The provider of TAFs to an Installation must meet regulatory requirements established by TC.

4.3 Ice and Iceberg Forecasting

The Operator should obtain forecasts of ice movements on a daily basis. The CIS ice charts are one such source of daily ice forecast information. As part of their Ice Management Plan, the Operator should have available sea ice and iceberg trajectory forecasting capabilities to address specific tactical requirements.

Date modified:

2021-09-16