Braving the gap windsDec 16, 2013
An off-season voyage from Mexico to Panama
Threatening clouds over the Mexican coast.
(page 1 of 2)
We slipped out of Guaymas, Mexico, in the northern Sea of Cortez, in late October aboard our Tayana 37 sloop Anna. This was only the first part of a 2,500-nm passage from northern Mexico to the Perlas archipelago in the Gulf of Panama. A trip that would take us through the dreaded Gulfs of Tehuantepec and Papagayo with their possible gale-force winds and choppy seas.
There was no room for complacency on this trip, especially in October and November, along the near-offshore route to Panama. Late-season tropical storms, in the northeast Pacific Ocean, developed and spun off into hurricanes along the Pacific coast of Central America; and they were a threat into December.
Rich and Cat Ian-Frese’s Tayana 37, Anna.
Offshore or coastal routing
During the season of strong Papagayos (heavy northerlies lasting from December to May) the dangers of the coastal route can be bypassed with a direct 2,400-nm offshore passage from the southwest tip of the Baja Peninsula to the Gulf of Panama. This route would skirt the Gulf of Tehuantepec and the Gulf of Papagayo by as much as 500 nm, off their respective coastlines; both of these gulfs can be ferocious from November through April.
The offshore route, however, has its own idiosyncrasies. In addition to the intermittent tropical storms and hurricanes that track through at the tail end of hurricane season, are the variable winds and counter currents, interspersed with calms and squalls and large, tedious, sloppy seas. This mixed bag of unfavorable ocean conditions during the off season had us pondering the merits of the near-offshore strategy; a route where careful timing of the Gulf of Tehuantepec and the Gulf of Papagayo crossing took top priority.
We weighed the existing weather and sea conditions, computer model forecasts, normal seasonal patterns and anomalies, and then thought about how much of a beating we would be prepared to take when conditions fell apart; and we concluded that the near-offshore strategy, from the northern Sea of Cortez to Panama, was preferable during the months of November through April. But if the weather window at Tehuantepec or Papagayo shut down — and a strong probability existed that it would — then we could get seriously hung up, possibly for weeks or more.
We made three stops en route to the northwest entrance of the Gulf of Tehuantepec. We could wait in Huatulco, Mexico, for good conditions to complete the 250-nm crossing of the Tehuantepec. We would pick up our international zarpe (exit clearance papers) in the Port of Chiapas, Mexico, and continue on to Central America.
Our strategy for crossing the Gulf of Tehuantepec was to skirt the curve of the beach, close to shore, where the fetch of the wind waves across the gap at the north side of the isthmus would have no chance to develop. We could still get hammered by the wind, but it is the progressively larger, breaking seas, farther out, which cause the bigger headache. Cutting across the center of the Gulf, on a rhumbline course to Chiapas, while a bit shorter, is exponentially more risky in the off season.
Alfred Wood/Navigator Publishing illustrations
Inshore and offshore routes from Mexico to Panama.
Gap wind areas: 1) Gulf of Tehuantepec, 2) Gulf of Fonseca, 3) Gulf of Papagayo and 4) Gulf of Panama.
On Dec. 20, a storm warning was issued for the Gulf of Tehuantepec: 50- to 60-knot winds were forecast to funnel through and generate 20-foot breaking seas with a six-second period between wave peaks. It was expected to settle down on Dec. 23, for 48 hours — not enough time to transit before the next wind event was forecast to blow through.
Late on Dec. 23, weather guidance shifted and indicated a 60-hour window opening up on Dec. 24; wind and seas would abate. The tight isobars were easing up in the Gulf of Mexico (on the opposite side of the isthmus) and promised to give Anna an opportunity to push across the Tehuantepec before it closed down once again.
In the Tehuantepec, the gap winds are heaviest in December and January. Both early November and May are considered the optimal times to complete the crossing, unscathed. But contrary to the rule of thumb, we found that November was fraught with storm activity. December, on the other hand, had at least two good weather windows where sailing was a viable option for a good portion of the ride across.
Anna departed early on Dec. 24 to make Chiapas and arrived in 54 hours. We based our decision to go on the concurrence of three GRIB models: the COAMPS, WW3, and GFS. It was a good decision; the models had been exhibiting consistency and accuracy over time, and therefore, our level of confidence in them had been reinforced. We had the predicted head winds, but also a strong current in our favor — Anna zipped along at 7 to 8 knots for the first 80 nm; a very good start. Then the current reversed and we had 2 to 3 knots against us for the next 70 nm — slower going, but we still maintained 4 to 5 knots through the water. The last hundred miles offered us an indifferent current and a light variable breeze, changing in direction from hour to hour. Over the 54 hours it took Anna to complete the crossing, the wind waves and swell were of small to moderate size, and well spaced.
For the 100-nm stretch from Salinas to Solo Dios we rounded the isthmus within four miles of the beach. This would give us the option, if necessary, of coming in just two miles and anchoring in 30 feet of excellent holding sand — to take a rest, sleep, or wait for conditions to ease. We opted not to anchor along the open roadstead as we wanted to put as much distance as possible behind us while good conditions prevailed. We knew that once we made Solo Dios, on the eastern shoreline — about two-thirds the way around the Gulf to Chiapas — the winds would slacken. Even if the forecast fell completely apart, the heavy funnel effect of the gap winds rarely reach beyond Solo Dios.
Our easy crossing of the Tehuantepec was remarkable. We had only one surprise: we were able to use our full, unreefed mainsail and fly our drifter for long stretches.
With the Tehuantepec now in our wake, the toughest leg was behind us — or so we thought, until we met Tehuantepec’s evil twin, the Gulf of Papagayo and the 125 nm of contemptible coastline leading up to it. With weather windows of 12 hours or less, from the well-protected industrial Port of Corinto, Nicaragua, to the windy, but safe haven of Bahia de Salinas, Costa Rica, the coastline would offer no true protection from severe weather and seas.