Many of you are aware that we experienced a major hurricane on the 23 rd of October. After getting many emails to ask us how we were I decided it was about time I got this Blog up and running again. I was just waiting for something exciting to write about. Well excitement we got and then some! I do not want to worry any of you or keep you in suspense so I will tell you the ending before I begin. We are fine and the boat is fine. There were some nervous moments but all is good with the world and things are almost back to normal.
Just a little side bar: I was going to return to the Blog with a short recap of what we did this summer. I had the script all written and when I went to copy and paste it into the Blog I cut it instead. That means I have to rewrite the whole thing. Well that could take a while and I am sure you are more interested in the hurricane so I have decided to post this first and tell my story about our summer later.
Once I started writing I realized that this edition was turning into a chapter in a book. So I have decided to divide it into three parts. In keeping with my past Blogs, I have always tried to explain aspects of our sailing adventures to those reading this Blog who are not sailors. You got it - that means another education session - Hurricanes 101!
So Part One will try to do that. The experienced sailors may want to skip this part except for the specific characteristics as they applied to Hurricane Patricia. Part Two will describe exactly what we went through, our experiences with the people, the destruction and the unbelievable attitude of the Mexican people in this area to deal with the situation. Part Three will be the aftermath.
First of all you may hear a hurricane called a typhoon, a cyclone, a tropical revolving storm or a willy- willies. I kind of like the last one! But what it is called is usually related to what part of the world it occurs in. It is called a hurricane once the wind speed exceeds 64 knots. But wind alone does not define it. It also has to have certain characteristics that go with the speed.
The formation of a hurricane begins as the winds blow around an area of low pressure. In the northern hemisphere this occurs in an anti- clockwise direction. As the wind moves towards the center it begins to spiral causing it to get sucked even further into the center or core. This core or eye defines the hurricane.
Hurricanes in this part of the world usually get their start between 7* and 15* latitude on either side of the equator. The breeding ground is the Intertropical Convergence Zone (ITCZ) where the two opposing trade wind systems meet. During the hurricane season starting in May the ITCZ starts to move north into Mexican waters. In our case this area of low pressure or tropical depression originated in the Gulf of Tehuantepec. Remember when we crossed that area last year? - at the narrowest part of Mexico.
They usually travel about 10-12 knots and head in a NNW to NE direction. Note that this is the direction of the movement of the depression and not the direction of the wind! During the summer the sun heats up and the sea water heats up warming and moistening the air above it. It is actually the revolution of the earth on its axis that creates the counter clockwise spin on the rising air current (Coriolis effect). It is the combination of the low barometric pressure, the warm water temperatures and the increased moisture that results in the formation of the hurricane. And it is the heat that is released when the water vapor condenses that gives the hurricane its energy. So as long as the hurricane remains over warm water its energy supply is endless.
And this is exactly what happened with Patricia. In Patricia's case the barometric pressure was the lowest ever recorded at 880 millibars. The sea temperature was also warmer than normal at 29 C. El Niño and global warming? The winds were also light in the upper atmosphere preventing any shearing effect on the top part of the formation. When these winds are strong they can help to cut down the strength of the hurricane and disrupt the eye. This did not happen.
Through most of the summer these winds tend to travel in a WNW direction and die in cold waters as they approach Hawaii. All of the Hurricanes this summer have done just that, including Carlos which threatened us in late June. But come October their movement can become a little more erratic, intensifying rapidly, recurve and hit the Mexican coast. This is exactly what happened with Patricia.
So during this time of the year you just do not want to be sailing on this part of the coast. What you do want to do is find an area along the coast that will provide you with some sort of protection. These are referred to as Hurricane Holes and though no area is completely safe certain ones have a history of being safer than others.
Barra de Navidad, particularly the marina on Isla de Navidad, and the place where we have kept our boat for the last two summers, is one of those holes. The location is 19* 12.0" N 104* 41.4 " W.
Punta (Point) Graham provides excellent shelter for the marina and adjacent hotel. In the picture below you can see the town of Barra in the foreground. On the other side of the entrance to the lagoon is the hotel and marina tucked in at the base of the hill. In fact parts of the hill are actually cut into the Rock.
So the point not only provides a nook away from the main coast but the elevation also provides protection. Think of Gros Cap or Horshoe Bay.
The grey dot denotes the location of the marina and hotel.
Surges could have been an issue but in this case Patricia was kind and there was really only one surge that raised the docks within three feet of the top of the pilings. The design as well as the location of the marina makes it a pretty safe place to keep the boat. The marina basin has been dredged out so it is lower than the lagoon and all pilings are 4-5 feet above ground level.
There is one aspect of a hurricane that I still need to explain before I get to Part Two and what we experienced.
A hurricane is divided into quadrants, mainly for the purpose of determining the safest point of sail when you are caught in a hurricane. Of course the best thing is to avoid the hurricane altogether. But when you are stationary you just end up in whatever quadrant you end up in.
Take the circle of the hurricane and draw a cross through it with the y axis pointing in the direction that the wind is going. The right top quadrant is the most dangerous one. The right lower quadrant is less dangerous but still not a place you want to be. You really want to be in the left lower quadrant.
In respect to our location, we were in the top right quadrant as the front of the hurricane passed over us. The eye touched land 29.5 miles to the north of us. The red dot is where Patricia went to shore. The blue dot was our location.
This put us in the wall of the eye of the hurricane!
That is pretty darn close! After the eye passed then the winds changed and we were sitting in the lower right quadrant. Still a pretty dangerous situation. The winds were measured at 165 mph where it came ashore and maxed at 75-100 where we were. We think the only reason why they were slower right in the marina and the hotel was due to the elevation of Ponta Gordon!
So if you go back to this picture of Punta Gordon I will try to explain how the wind approached us.
If you draw a line from the dot to the bottom of the yellow circular road you get the direction of Patricia before the eye passed. If you draw a line from the dot to the end of the red line right on the shore y get the direction of Patricia after she turned and produced her strongest winds. But as you can see the point helped shelter us from some of it.
By 0700 it had moved quite a ways inland, ran into the mountains, lost a lot of its power and petered out! It was a wild 12 hours! Saturday turned into a sunny day, light winds and no rain.
So now that you know everything that I know about hurricanes it is time to go to Part Two. What did we actually experience? I will warn you. It was nothing as dramatic as what the news was reporting! But I have to say, and David will agree, the potential of what could have happened could give one nightmares!
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