Conveniently located some 500 miles southwest of Gibraltar, the Atlantic island groups of Madeira, Canary and Cape Verde are ideally placed stepping stones for a voyage from the Mediterranean to the Caribbean. These islands lie along the northeast trade winds on the route favored by sailors crossing back west.
Along with their natural beauty and favorable trade-wind weather, these islands also have their own special winds and ocean currents, resulting from their location close to the convergence of the northeast and southeast trade winds, an area called the Inter Tropical Convergence Zone.
The Madeira Archipelago is exceedingly beautiful with high mountains peaks and large valleys. Along the south coasts, the land slopes gradually to the interior, while the north and west coasts are high and bold. But there are a few well sheltered harbors, the most known are Funchal, located on the south side of Madeira, and Baia de Porto Santo, on the south side of Ilha de Porto Santo.
The Madeira Island are in the main southwesterly flowing Canary Current. Like a rock in the middle of a stream, the islands split the current, which flows around the islands. The current breaks at Porto Santo then rejoins south of Madeira. Eddies and swirling that extends some 4 or 5 miles off the coast occurs at this convergence. As unnerving as these eddies may be when first seen, they are in fact in deep water.
Madeira Islands, lying in the northeast trade-windbelt, do, indeed, experience year-round northeasterlies, but with an exception. In the summer and periods of hot weather, an afternoon sea breeze--a southerly--often builds, over-riding the northeast trade winds. You also will not find a northeaster on the south side of Madeira Island where, due to the island's mountains, the wind condition is actually calm.
Rising up to 6,141 feet, Madeira's mountain range extends east- west for the length of the island. Funchal is the major port and has an extensive marina which can accommodate yachts up to 60 feet and 13- foot draft.
The three-island Ilhas Desertas group is volcanic and rugged with steep cliffs and dangerous shoals lying up to 2 miles to seaward. There are few good anchorages in this group, which, in general, should be approached with caution.
An interesting underwater aspects of the Madeira Islands is the chain of sea mounts that extends out from the islands in a northeast direction. Recent oceanographic research indicates shoaling in their vicinity with resultant eddies and turbulence. Though most yachts will find little difficulty in passing over them, these sea mounts are avoided by ships. Notice to Mariners should be consulted prior to departure from Gibraltar or other European ports.
Pico de Teide, on the Island of Tenerife, is the highest. Rising to 12,269 feet, it makes for an impressive landfall. The Canary coastline is largely cliff and rock, with few lees. Due to the height of these islands, you can expect a wind shadow of up to 30 miles out on the leeward side. (Note: Calms and variable winds routinely extend from the lee side of an island to a distance eight times an island's maximum height on the lee side of an island.) Wind shadows have actually been detected as far downwind as 100 miles from mid-ocean islands. Determining how to pass such islands is a significant tactical decision. Around-the-world racers passing through the Atlantic give careful consideration to how they will pass the Canary and Verde islands.
La Palma, the most northwest of the Cararies, is frequently enveloped in fog, caused by the meeting of the warm moist Atlantic atmosphere and cooler Canary currents flowing through. There is a general haze that seems to set over the Canaries, making them a misy landfall that is not visible from afar. These islands also experience heavy swells and a strong west and southerly wind called El Caldereto. This wind, which can reach up to hurricane velocity, is often spurred by a passing mid-latitiude low pressure system to the north. Winds here tend to funnel, sometimes racing up to 15 to 20 knots faster than winds north or south of the islands. The current, on the other hand, is not much of a factor as it sets to the west at a knot.
The typical Canary breeze is northeast, with the exception of when a low pressure system passes to the north, typically in winter. This causes strong southerlies to blow and also brings large swells into harbors on the island's south side. It also causes formation of haze, reducing visibility to 5 miles or less.
There are several off-lying dangers near the Canaries that should be mentioned here:
Cape Verde Islands
In winter when trade winds become well developed, dust from the African continent becomes airborne wafting out into this Atlantic route. The dust is so prevalent it can cover the decks as well as reduce visibility down to only a few hundred yards. In this condition, distances are often difficult to judge and land is difficult to see.
Gales and mid-latitude weather systems are rarely experienced here but squalls can blow down from the tall mountains, which reach heights of up to 6,531 feet. Mountain-induced winds are often encouraged by strong trade winds.
Tide range is approximately 4 feet and tidal currents are weak and variable. There is one off-lying danger near the Cape Verde islands, a shoal named Baixo Joao Leitao, located at 15.8N/23.2W. It consists of coral and shell and is usually awash. Breakers can normally be seen on the bank except when the wind is calm. Fishing vessels are often seen in its proximity.
Onward to the Caribbean
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