More About Weather

Living on a sailboat, weather becomes a much more integral part of your life.  Good forecasts are important because if you get caught by surprise you can set yourself up to be quite uncomfortable and in extreme cases you can find yourself in real danger.  Unlike at home when we were primarily concerned with temperature highs and lows and whether it was supposed to rain, if we were concerned at all, out here we are much more concerned with wind speed and direction, and if planning a passage, what the sea state is supposed to be like.  When at a major port with internet access, getting these forecasts as often as we want is pretty easy.  But most of the time we are out at more remote anchorages without internet, so we rely solely on our SSB radio.  We have two ways to get weather forecasts via the radio: 1) Voice nets and 2) Data downloads (via the pactor modem connected to the radio).  There are two morning radio nets that provide weather forecasts.  The superior by far is the Sonrisa Net, which includes an extensive forecast by Gary (that I described in my last essay, Gary is the guy who hosted the cruisers 4th of July part at El Burro Cove).  The other is the Amigo Net, which includes reading wind and sea state forecasts from the solmatesantiago website.  This is actually not all that useful in the Sea of Cortez when you are just coastal cruising and hopping from anchorage to anchorage, because the winds can be dominated a lot by local landform effects, so there’s often the disclaimer that in the Sea of Cortez this forecast is good mainly for “down the middle.”  If I miss a voice net because I sleep in or don’t have good enough reception, not to worry, the information from both of these nets is also available to download.  The main way to download weather products is by using the saildocs service, which is a free document service for the bandwidth challenged.  There is an extensive NOAA weather product library, and solmatesantiago forecasts are also available.  Additionally, you can grab the text of any webpage using saildocs, and Gary actually uses voice to text software and publishes the text on his website, so that it can even be downloaded.  The main NOAA products we’ve used so far are tropical forecasts by the National Hurricane Center for the NE Pacific.  There is an “outlook” file that just tells you if there are any lows brewing and gives percent likelihood of it turning into a tropical cyclone.  Then there is a “discussion” file that goes a little more in-depth and provides more information than just tropical storms (like gap winds in the Tehuantepec).  And if there is a tropical storm in progress, there are storm specific files that can be downloaded that give details and forecast track and intensity.  Last, but not least, we can also download .grb files (“Gribs”) through saildocs.  We typically use these only when planning for our longer passages.

In addition to the low likelihood threat of a tropical storm, summertime in the Sea of Cortez brings another weather “feature” to look out for: the Chubasco.  A Chubasco is a very intense but relatively shortlived squall accompanied by thunder and lightning.  They are caused by convection over the land but have the tendency to move out into the sea any time from the late afternoon to early morning, but most common in the middle of the night.  I read some blogs from last summer’s cruisers and also talked with the folks on Interabang, who experienced a 60 kt Chubasco early in the summer last year.  Luckily, this year, Jake (on the sailboat Jake) started a nightly Chubasco report on SSB radio.  He was in or around Puerto Escondido all summer with internet connectivity, so every night he checked on the convection situation and then reported it out to all of us.  To be clear, there’s no way to really predict if a Chubasco will hit a specific anchorage.  However, Jake was able to let us know what convection was going on over on the mainland and whether we were likely to have a quiet night or whether we should be on alert.  The best reports were when Jake told us there was no convection.  Of course, hearing the report was sometimes a challenge if atmospheric propagation of the radio signals wasn’t cooperating.  Sometimes it seemed like some sort of sick joke what we could or couldn’t hear… it would often go like this, “This evening it should be quiet in the Puerto Escondido area, and up in BLA it SHHH–HISS–CRACKLE–HISS.  Any questions?”  Those of us up in the BLA area got in the routine that if we actually got a good copy on the report we would repeat it for everyone else, so most nights at least one person got it.  I took these Chubasco reports very seriously and woe to the Exodus crew member or even the guest on Exodus who talked or shuffled cards during the report.  I was never shy about shushing anyone!  When there was a threat of a Chubasco, or even if there wasn’t really, we started taking extra care to button up the boat at night.  We had no idea how Exodus would react to 60 kt winds, but we tried to put away and secure everything, so at least we wouldn’t lose any gear in the blow.  We also tied down the mainsail bag and secured the solar array panels.

We did end up getting what is affectionately called a “mini-Chubasco” when we were at Isla Partida.  That night on the Chubasco report, Jake was “cautiously optimistic” that we would have a quiet night, but we semi-secured everything anyway, just in case.  The wind woke us at about 2 am, and both Tim and I got up and quickly did some last-minute tucking in here and tightening up there.  We only saw about 22 knots sustained with gusts up to 30 kt, from all directions.  The lighting show was pretty spectacular though, so all the portable electronics (handheld VHF, laptop, iPads, iPhones, Camera) were quickly stored in the oven, an effective Faraday cage, for the rare chance we actually got struck by lightning.  We came through it completely unscathed, and the good news is our anchor held firm.  Love that Rocna!