Trade Wind Routes

Offshore Passage Planning · Global Routes

Every major ocean crossing that goes smoothly does so because someone understood the trade winds. These steady, reliable wind belts — blowing at 15 to 25 knots through thousands of miles of open ocean — are the foundation on which European exploration, the Age of Sail, and modern bluewater cruising were all built. Understand why the trade winds exist, and the routing decisions that baffle new offshore sailors become almost self-evident.

The trade winds are not simply weather. They are a product of the global atmospheric circulation system, predictable by season rather than by forecast, and stable enough that passage timing was planned by calendar rather than GRIB file for most of human sailing history. Modern sailors still consult pilot charts — the distilled averages of centuries of ship's log entries — when planning a trade wind passage, because the patterns are that consistent.

Why Trade Winds Exist: The Hadley Cell and the ITCZ

The tropics receive more solar energy per square meter than any other part of the planet. That energy heats the air at the equator, causing it to rise. The rising air creates a band of low pressure at the surface — the Intertropical Convergence Zone, or ITCZ — and, because rising air means reduced surface winds, this is the zone sailors have always called the doldrums. The ITCZ is where ships were becalmed for weeks in the pre-engine era. It remains a light-air slog for modern cruisers who cannot avoid it.

The air that rises at the ITCZ has to go somewhere. It flows north and south at high altitude, cools, and descends around 25–30° latitude. As it descends, it creates the subtropical high-pressure systems — the Azores High in the North Atlantic, the Pacific High off the California coast, the South Atlantic High — that govern the surface wind patterns in the trade wind latitudes. The descending air flows back toward the equator at the surface, completing the Hadley cell circulation. Because the Earth is rotating, the Coriolis effect deflects this surface flow: from the northeast in the Northern Hemisphere, from the southeast in the Southern Hemisphere. This is why the trade winds blow from those directions so reliably.

The ITCZ migrates north and south with the seasons, following the overhead sun with a lag of about six weeks. In Northern Hemisphere winter, it sits near or below the equator; in summer, it moves to 5–10°N across the Atlantic and further north across the Pacific. This seasonal migration determines the optimal windows for each of the major trade wind passages.

The Canary Island Hop: Atlantic Downwind to the Caribbean

The classic Atlantic trade wind route is among the most-sailed offshore passages in the world. The departure point is the Canary Islands — specifically Las Palmas de Gran Canaria, the traditional staging harbor — and the arrival is the Eastern Caribbean, typically the island of St Lucia (the ARC finish) or Barbados (the landfall of choice for many independent passages). The distance is approximately 2,700 nautical miles. In the northeast trades, at a comfortable 6–7 knots average, that is 18 to 25 days at sea.

The timing is late November. The ARC — Atlantic Rally for Cruisers — departs Las Palmas in the third week of November, a date chosen because the NE trades are reliably established by then and hurricane season in the Caribbean has officially ended. Independent sailors have learned from the ARC's timing. Departing before mid-November risks catching the trades before they have filled in; departing in December means arriving in the Caribbean during the peak of the Christmas charter season.

Many boats stop in the Cape Verde Islands, 900nm south of the Canaries, before the final 1,800nm run to the Caribbean. Cape Verde puts you further south, closer to the latitude where the NE trades are most reliable (15–20°N), and reduces the risk of light air in the first few hundred miles out of the Canaries. The tradeoff is the extra stop and the slightly longer total distance. For boats that find the trades slow to fill in north of 20°N, the Cape Verde stop is good insurance.

The passage itself, once in the trades, is sailing as it is supposed to be: a steady wind from astern or the quarter, no cold fronts, no complex routing, warm air, and the simple task of keeping the boat moving downwind for two to three weeks. Most boats fly a poled-out headsail or a spinnaker. Watch schedules settle into a rhythm. Fishing lines go out. The daily mileage becomes the organizing fact of shipboard life.

The Pacific Trade Wind Route: Mexico and Panama to the Marquesas

The Pacific trade wind crossing is longer than the Atlantic — approximately 3,000 nautical miles from the west coast of Mexico or Panama to the Marquesas — and in some ways more demanding, because the ITCZ crossing is unavoidable, and the Pacific ITCZ is wider and more variable than its Atlantic counterpart.

The optimal departure window is March through April. Leaving from Mexico (Cabo San Lucas or the Banderas Bay area around Puerto Vallarta), boats head south to get into the SE trade wind belt before turning west. The ITCZ must be crossed somewhere between 5°N and the equator, and the strategy is to cross it quickly: sail south on a direct track, minimizing time in the light-air, squall-riddled convergence zone, and pick up the SE trades as soon as possible south of the equator.

The width of the ITCZ on the Pacific varies considerably by season and year. In the optimal March–April window it may be as narrow as 200nm; in other seasons or years it can stretch to 500nm or more. Boats that leave too early (January–February) often find the ITCZ at its widest and the SE trades light on the far side. Boats that leave after May are sailing into the early hurricane season north of the equator. March and April are the window for good reason.

South of the ITCZ and into the SE trades, the Marquesas are a straightforward downwind run. Nuku Hiva is the typical landfall — a dramatic volcanic island with a well-protected anchorage at Taiohae Bay. From the Marquesas, the Pacific cruising circuit opens up: the Tuamotus, Tahiti, the Cook Islands, Tonga, Fiji, and beyond.

The South Atlantic: Cape Town to Brazil

The South Atlantic trade wind route runs from Cape Town, South Africa, to Brazil — typically Salvador (Bahia) or Recife — a distance of roughly 3,500 nautical miles. This passage is less frequently sailed than the Atlantic or Pacific crossings but follows the same logic: the SE trade winds blow steadily in the South Atlantic between roughly 5°S and 25°S, and a boat heading west in that latitude band will have wind behind it for most of the passage.

St. Helena — the remote British Overseas Territory famous as Napoleon's final exile — sits almost exactly halfway across the South Atlantic at 15°S, 5°W. It is the natural stopping point on this crossing: a well-protected anchorage in Jamestown Bay, reasonable provisioning for such an isolated place, and a fascinating historical curiosity. Boats making the South Atlantic crossing often plan their departure from Cape Town specifically to arrive at St. Helena, then continue west to Brazil after a few days.

The timing for the South Atlantic crossing is typically March through May for boats completing a circumnavigation or sailing the Southern Ocean circuit. The SE trades are well established in this period, and boats arriving in Brazil in April or May can then head north through the Caribbean before the Atlantic hurricane season.

The Indian Ocean Trades: Chagos to Reunion

The Indian Ocean trade wind circuit is the least-discussed of the major trade wind passages, but for circumnavigators completing the route through SE Asia and down the east coast of Africa, it is the critical link. The standard route runs from the Chagos Archipelago (British Indian Ocean Territory) west to Rodrigues, then Reunion (or Mauritius), before the final leg around the Cape of Good Hope.

Timing here is dictated by cyclone season. The Indian Ocean cyclone season runs roughly November through April in the southern Indian Ocean. Boats transiting this route must clear the cyclone-prone latitudes by late November or early December — which means leaving SE Asia or Thailand no later than October, transiting the Strait of Malacca, crossing the Bay of Bengal, and arriving in the Chagos area before the cyclone season closes the route. Reunion and Mauritius are generally considered safe from major cyclone strikes, but boats caught in the open Indian Ocean in January or February are in a dangerous position.

The ITCZ Problem: Crossing the Doldrums

The Intertropical Convergence Zone is the obstacle on every trade wind passage that requires crossing the equator or near-equatorial latitudes. The ITCZ is not a wall — it is a band of disturbed, variable weather characterized by light winds punctuated by violent squalls, heavy rain, and confused seas. It can be 100 miles wide or 500 miles wide. It can be crossed in 24 hours or it can take a week.

The strategic options are: motor through it as fast as possible, accepting the fuel cost; sail through it, accepting the frustration of variable winds and frequent sail handling; or find the narrowest part of it. The ITCZ is narrowest in the eastern Atlantic (around 20–25°W) in the November–December window, which is one reason the ARC route works as well as it does. In the Pacific, the ITCZ is narrowest in the March–April window on a track south from Mexico.

Experienced offshore sailors treat the ITCZ as a cost of passage rather than a planning failure. Run the engine when the wind dies below 5 knots; shorten sail aggressively when squalls appear on radar; accept that this part of the passage will be uncomfortable and slow. The trades on the other side are worth it.

GRIB Routing vs. Trusting the Season Patterns

Modern passage planning involves a tension between GRIB weather file routing — which gives you a 7 to 10 day forecast of wind and sea state — and the season-pattern thinking that has guided offshore sailors for centuries. For trade wind passages, the season patterns usually win.

GRIB files are most useful for departure timing: choosing the specific day to leave based on the next week's weather, particularly for getting out of port and through the first few days of a passage before the boat is well offshore in the trade winds. Once in the trades, the daily GRIBs become more confirmatory than directive — they tell you the trades are holding, which you already knew from the pilot chart probability statistics for that month.

Where GRIB routing genuinely earns its value on trade wind passages is the ITCZ crossing and any light-air zones at the edges of the trade belt. Weather routers with satellite access and specialized tropical forecasting models can often identify a narrower ITCZ crossing window, a developing disturbance to avoid, or a brief strengthening in the trades worth waiting a day to catch. For shorthanded offshore sailors on their first trade wind passage, a weather router consultation before departure is a reasonable investment.

← All Sailing Routes  |  Circumnavigation Routes →

Frequently Asked Questions

What atmospheric mechanism creates the trade winds and why are they so consistent? The tropics receive more solar energy per square meter than anywhere else, heating equatorial air until it rises — creating the low-pressure band called the Intertropical Convergence Zone where surface winds are light or absent. The risen air flows north and south at altitude, cools, and descends around 25 to 30 degrees latitude, creating the subtropical high-pressure systems. As descending air flows back toward the equator at the surface, the Coriolis effect deflects it northeast in the Northern Hemisphere and southeast in the Southern Hemisphere. This Hadley cell circulation is why the trade winds blow so reliably from those directions.

What is the classic Atlantic trade wind passage and what departure timing does it require? The classic route runs approximately 2,700 nautical miles from the Canary Islands — specifically Las Palmas de Gran Canaria — to the Eastern Caribbean, typically St. Lucia or Barbados. The passage takes 18 to 25 days in the northeast trades at 15 to 25 knots from behind. Departure timing is late November: the ARC departs in the third week of November because the NE trades are reliably established by then and Caribbean hurricane season has officially ended. Departing before mid-November risks catching trades before they fill in; departing in December means arriving during the peak Christmas charter season.

Why is Cape Verde worth considering as a stopover on the Atlantic crossing? Cape Verde, 900 nautical miles south of the Canaries, puts boats further south and closer to the latitude band where the NE trades are most reliable — 15 to 20 degrees North. Stopping there reduces the risk of light air in the first few hundred miles out of the Canaries before the trades establish. The tradeoff is the extra stop and slightly longer total distance. For boats that consistently find the trades slow to fill in north of 20°N, the Cape Verde stop is good insurance against days of drifting in light air early in the passage.

What is the Pacific trade wind crossing departure window and what makes the ITCZ crossing challenging? The optimal Pacific departure window is March through April. The Pacific ITCZ — the Intertropical Convergence Zone — is both wider and more variable than its Atlantic counterpart, ranging from 200 to 500 nautical miles depending on season. In March and April it is at or near its narrowest; boats departing in January or February find it at its widest with SE trades light on the far side. Boats departing after May sail into the early hurricane season north of the equator. The crossing from Mexico or Panama to the Marquesas is approximately 3,000 nautical miles.

What is the strategic choice when crossing the ITCZ doldrums? The three options for crossing the ITCZ are: motor through as fast as possible accepting the fuel cost; sail through accepting variable winds and frequent sail handling; or find the narrowest crossing point. The ITCZ is narrowest in the eastern Atlantic around 20 to 25 degrees West in November and December — one reason the ARC route works as well as it does. In the Pacific it is narrowest in March and April on a track south from Mexico. Experienced offshore sailors treat the ITCZ as a cost of passage rather than a planning failure: shorten sail aggressively for squalls, run the engine when wind drops below 5 knots, and accept that this section will be uncomfortable and slow.

When does GRIB weather routing add value on trade wind passages versus trusting seasonal patterns? For trade wind passages, seasonal patterns from pilot charts usually win over short-range GRIB forecasts — the patterns are that consistent. GRIB files are most valuable for departure timing, choosing the specific day to leave based on the next week's weather, particularly for getting through the first few days before reaching open ocean in the steady trades. Once established in the trades, daily GRIBs become confirmatory. Where GRIB routing genuinely earns its value is at the ITCZ crossing, where weather routers with specialized tropical forecasting models can often identify a narrower crossing window or an approaching disturbance.