Ports.com

ACAPULCO

THE DECISION TO SORTIE OR REMAIN IN PORT

General

Under normal circumstances, the decision on whether to sortie or remain in port is largely based on the answer to a single question: Would the vessel in question be better off attempting an evasion at sea or remaining in port?

Evasion rationale should include consideration of the following general factors:

1. Vessel characteristics
2. Berth and anchorage conditions
3. Most recent tropical cyclone warning advisory
4. Tropical cyclone climatology

Individual vessel characteristics and berth/anchorage conditions are best determined by those responsible for each vessel and local port authorities. Tropical cyclone warnings are issued by the Naval Pacific Meteorology and Oceanography Center/Joint Typhoon Warning Center Pearl Harbor for Department of Defense assets and are rebroadcast over the weather channel in Mexico. The interpretation of tropical cyclone climatology is addressed in the following sections.

Evasion at Sea

Evasion at sea is not the recommended course of action for ships at anchorages or berths in Acapulco.

Commanding officers and ship masters with access to tropical cyclone warnings and advisories coupled with OTSR services are most capable of making the safest and most prudent decision for successful storm evasion and avoidance. In all sortie situations, OTSR services should be requested and utilized. The best sortie route in a specific tropical cyclone scenario is largely dependent on the location of the tropical cyclone and the forecast track. During any tropical cyclone threat there is normally one to three options available to the commanding officer and ship master. Selection of the best option is the objective of all concerned!

Keeping in mind that tropical cyclones normally approach the Port of Acapulco from the southeast, the following guideline is offered: An evasion route to the west-northwest would provide following wind and sea for almost all approaching tropical cyclone situations once the T is crossed. However, storms originate normally within 72 hours of CPA south of the Port, which allows very little time and margin of safety to depart from the Port, cross the T, and maneuver to evade northwesterly heading tropical cyclones.

In all cases, the timing of the evasion is affected by:

1. The time required to make preparations to get underway
2. The time required to reach open water and gain sea room
3. The forward speed of the tropical cyclone
4. The radius of hazardous winds and seas that can adversely impact a vessel's ability to reach open water.

Remaining in Port

Remaining in port is the recommended course of action for all ships at the primary pier or at anchorage in the Port of Acapulco. An anchorage is considered to be the safest location during a worst-case scenario. Use of the primary pier is not recommended since it can be impacted by swell from passing tropical cyclones. Vessels may be required to shift to a different anchorage based on the recommendation of the Pilots or the Captain of the Port/Harbor Master and the track of the storm. Note that Designated Anchorage Positions "A" and "B" are less exposed to the open ocean than Designated Anchorage Position "C".

Source: http://www.nrlmry.navy.mil/port_studies/thh-nc/mexico/acapulc/text/sect8.htm