Time to Transit the Gulf of Tehuantepec?
Spring has sprung, and summer is approaching, so boaters throughout Mexico are discussing where they will spend hurricane season 2023. This column will discuss each of the most likely choices over the next few weeks.
Basically, the options are (1.) bash back up the outside of Baja. But that’s no fun.
Or (2.) cruise slowly up to the northern end of the Sea of Cortez, where hurricanes seldom reach, and spend summer bouncing between three primary hurricane holes up there.
Or (3) reserve a 4- or 5-month slip in one of the five hurricane-hole marinas in the lower Sea of Cortez and Jalisco.
Or (4.) scoot safely south of Mexico’s hurricane-nursery zone to meander among the many cruiser marinas of El Salvador, Nicaragua, Costa Rica, and Panama.
In the following few issues, we’ll discuss each of these options, but first, let’s explore option (4.), starting with why it has to be first.
Tropical storms in the eastern Pacific are normally born in the waters just off southern Mexico’s Gulf of Tehuantepec. (See graphic.) These summer storms are born as early as mid-May as Tropical Depressions by feeding on the increasingly warm seawater. Because cyclonic storms must spin counter-clockwise (Northern hemisphere, remember?), they generally travel northwest following the Mexican coastline. By staying coastal, sailing from Barra de Navidad (hurricane hole) down to Acapulco is easy.
But the tricky part of the option (4.) is getting through the Gulf of Tehuantepec. And we need to do that pretty soon, or one of those baby storms might block our route further south.
As Captain Jack Aubrey would say, “Time is of the essence!”
KNOW WHEN TO TRANSIT TEHUANTEPEC
The traditional rule of “Keep one foot on the beach” is a bit outdated thanks to advanced onboard communications – unless you’re an absolute Luddite and traveling blind to any developing weather.
Star Link works all the way down Mexico, thank heavens, and – trust me – southbounders at this time of year will share every shred of information about the weather ahead.
From Barra South to Acapulco, we’ll monitor at least the local marine-weather forecasts for southern Mexico, which all the Port Captains broadcast on VHF 16 and 22 daily at 0800 in Spanish and 0900 in English.
But we’ll also look for any “easterly waves” of low pressure that are quickly moving west across the western Caribbean or Gulf of Mexico because a deep wave (29.35 to 29.75 MB) there can actually cross over into the Pacific and foment a new Tropical Depression.
The originator of this arcane pressure-wave data is the National Weather Service’s telecom station NMG (November Mike Golf) in New Orleans, broadcasting 24/7 over SSB, WX-fax, and Ham radio frequencies. Boats lacking HF radio capability can always ask neighbors on VHF or might temporarily hire a weather-routing service. We’d ask our router to notify us of any suspicious easterly waves.
A gale predicted in the Gulf of Tehuantepec is even bigger news on NMG. (See chart.)
WEATHER WINDOW TO GO
Punta Sacraficios is where we’ll turn into the Gulf of Tehuantepec and can tell by any large waves if a “T’peck” gale has already started. But at cozy Marina Chahue in Huatulco, we’ll fuel up and wait until we get a favorable “weather window.” That means it’s predicted to stay open long enough for the boat (depending on max speed and navigation ability) to get safely to Marina Puerto Chiapas on the other side.
Many cruising boats hang out around Huatulco while awaiting their window, so here’s a chance to temporarily buddy boat with a similar vessel able to run at the same speed and having similar crew capabilities. The faster power boats can run at fast cruises. Most sailboats will probably have to motor overnight, and the slowest ones plan for perhaps two overnight runs. Get rested up because the helm is usually draining.
WHICH ROUTE? (See chart.)
With an appropriate weather window, we can lay a 260 n.m. course (note the straight red dotted line) directly across from Huatulco to Puerto Chiapas. This is the easier route, but it means being as far as 60 n.m. offshore, where it’s no place to break down. Also, we’ll ensure everyone onboard is OK with being out of the sight of land for a day and a night.
On the other hand, if we’re unsure of our weather window’s predicted duration, we could parallel the gulf’s curving coastline staying two nautical miles offshore (note the curving red dotted line). This is the traditional “one foot on the beach” route. We can handle this method as long as (1.) we monitor VHF 13 and 16, stay well outside Salina Cruz’s ship anchorage and busy traffic lanes, and (2.) we also jog 90° out to 10 fathoms and then 90° back in again to avoid two specific shoals: off Boca San Francisco and off Boca Tonala.
If a gale is blowing along the eastern half of this gulf, we might travel as close in as 36 feet of water. But this requires diligent hand steering while constantly adjusting our course in small increments to avoid getting in too shallow or out into the fray. It also requires a finely tuned radar (changing range frequently) and an accurate depth sounder at night. Some recreational boats hire a professional watch stander specifically for this inshore route.
If a gale is blowing on this inshore route, our waterline will get slapped by the tops of small wind waves, the spray might require windshield wipers, and our decks might acquire drifts of beach sand. But at least we’ll avoid those huge and dangerously breaking seas found 60 miles out.
During an infamous Tehuantepec gale, your nautical neighbors on this inshore route will likely be professional delivery skippers, big tournament sportfishers, rusty old shrimpers, commercial fishing vessels, and a few veteran cruising boaters like ourselves.
WHY GO THERE?
Not every boat crossing the Gulf of Tehuantepec is fleeing the start of hurricane season in Mexico. Throughout the year, several hundred sportfishers fish the world-famous tournaments in the coastal waters off of Costa Rica’s Papagallo and Nicoya Gulf. Another hundred cruising yachts pass through Tehuantepec to visit Costa Rica’s rain forests or to snorkel and scuba dive through magnificent coral reefs off Panama’s Isla Coiba National Park.
Most of our fellow boaters are en route to transit the Panama Canal from the Pacific into the Caribbean – or heading back north toward the U.S. West Coast.
Next issue, we’ll look closely at option (3.) for summering over.