Huat’s Up? Crossing the Tehuantepec

 

Screenshot of the weather forecast app, Windy, showing the next T-pecer
coming in about a week.  Gusts are predicted to blow 50+ knots.

The Challenge of the Tehuantepec Gulf

We arrived in the small coastal town Huatulco (waa tool kow), Oaxaca (waa haa kuh) after crossing the notorious Gulf of Tehuantepec (tuh wahn tuh pek).  For weeks we studied and agonized over the wind intensities that streamed blue, green, yellow, red and purple on weather models mapped over our proposed route.

For mariners, the Tehuantepec Gulf is one of the most respected bodies of water in the region for good reason. Beginning in the fall and continuing to early spring of each year, a violent north wind (“mountain gap wind”) originates in the Bay of Campeche in eastern Mexico and travels through the Chievela Pass on the isthmus. “T-pecers”, as they are called, are commonly sustained gale force winds (>25 kts) with even higher gusts. On occasion the winds may be over hurricane force (> 75 kts). Similar to putting your thumb on the end of a garden hose, the geography of the isthmus and mountains compress and increase the force of the winds that blow from shore and far out to sea. These winds can be relentless for 4-5 days or more, only to die down for a few days and then begin again.   

It is not just the winds but the waves propagated by the T-pecers that demand attention. Wave height and period are influenced by the force and the duration of the winds, as well as, the fetch, or the size of the area over which the winds blow. Combine the extremes of the high winds that blow for days over a large area, and the seas will build to dangerous and frightening conditions for even the most seasoned sailor.  Wave heights in such extreme conditions can be over 20 feet.

 

Watching and waiting for the monster to go to sleep

We imagined we were waiting for the mythical “monster” of the t-pecer wind to take a nap. To traverse the Tehuantepec Gulf going either north or south, sailors typically time their passage to coincide with a lull when the winds and seas have died down, at least for a few days. One strategy is to time the crossing with light winds and motor as fast as you can on a direct line to the other side. Another strategy is to “keep one foot on shore”, or follow close to shore (1/4 to 1 mile) to reduce the wind and “unkindly” seas.

 We waited, watched, and finally, along with two other sailboats, we saw the weather models project that the winds would decrease and remain low for several days. Although the lighter winds were not optimal for sailing, we were prepared and happy to motor the entire passage if we needed to.

Sunset at Marina Chiapas as we wait for a weather window

Recall cruising sailboats, including Leilani, are not racing boats. We use an average of about 5-6 knots (~ 5.7-6.9 mph) to estimate our passage time. We decided to stay close to shore and take the longer passage of about 250 miles. We made a conservative estimate of about 48 hours to make it across to our destination, Huatulco.

The track from our passage across the Tehuantepec Bay. 
We stayed close to shore, around 5 miles offshore, for most of the passage,
but hugged the coast as we approached the strongest winds. 

How did it go?

We left Marina Chiapas around 4 pm on November 9^th, with just enough light to navigate out the channel and after a 48 hour passage, allow us to arrive in daylight.  Seas were fairly calm and winds were light, around 5 knots.  We put up the genoa and anxiously motor-sailed toward the T-pecers.  About 10 hours into the passage the winds picked up to around 15 knots and continued to increase to 20-30 knots as we navigated through the strongest section of the T-pecers, with gusts up to 33 knots.  With a current in our favor and the genoa double reefed, we were cruising over 7 knots.  As soon as we cleared the shipping lanes at Salina Cruz and hugged the coast, the winds started decreasing.  The worst of the passage was over.  About 42 hours from when we left, we arrived at our anchorage in Bahia Conejos.  After dropping the anchor and having a celebratory rum, it was time for a much needed nap.

Sunrise on the first morning

A witch moth joined us for part of our journey.

Conditions were comfortable just before the winds started picking up.

We had a bit more wind than expected, but the winds were manageable.  Keeping the genoa sail to the size of a handkerchief ensured we wouldn't overpower the boat, and gave us some extra speed.  We averaged 6 knots over the passage, which got us to the anchorage about 6 hours earlier than expected.  It also meant that we arrived at the strongest winds sooner than expected and before they calmed down completely. 

Pelicans dove into fish balls like this one just before the winds really picked up.

Sunset on the second evening

 Taking in the new scenery as we approach Huatulco

We hope you all will have wonderful holiday season. We will be moving on north to Acapulco in about a week. That is the extent of our plans for now.