We are currently in position 04 01S 036 36W, saillng at 5 knots on a course of 350M. The wind is E at 10-12 knots with a slight sea and short 1.5m SE swell. We are sailing under full main and double-furled yankee. Scattered small cumulus. Our day's run was 112nm, our DMG was 88nm and we have 1955nm to go.
The speed and course above are our speed through the water and our heading. Our SOG (speed over the ground) is 6.0 knots and COG (course over the ground) is 335M, so we have over 1.5 knots of current flowing approx 290M. Nice! Quite close to that predicted by RTOFS.
Below is a screenshot from the routing app qtVlm showing the ocean currents for today off the Brazillian north coast. Yellow is up to1 knot, orange is 1 to 2, red is 2 to 3 and the dark blue offshore area has over 3 knots! The current flows strongest along the continental shelf. QtVlm can take these currents into account when producing routes from A to B, as well as wind data and the boat's polars of course.
RTOFS GRIB
Yesterday afternoon the winds were ESE at 8-10 knots which made progress a little slow. During the afternoon we noticed we had an escort of several fish, each about 0.3m in length. They seemed quite happy to keep us company. Later a pod of dolphins sped past our bow, clearly on an important mission elsewhere. It's always a treat to see dolphins at sea. The water here is very clear and we could see the dolphins when they were well underwater. Although we're off the continental shelf there are an array of shallow sea-mounts along this coast and they probably attract a lot of sea life.
At sunset we gybed onto port and headed WSW to close the coast and get into the current. This "zig" reduced our DMG for the day but hopefully sets us up for good current for several days. For much of the night winds were 6-8 knots and we were struggling to keep the boat speed over 3.5 knots.
Around dawn a bank of clouds came over and the wind backed to ENE and picked up to 8-12 knots or so. By that time we were in good current and there were an array of lights - probably fishing boats - several miles ahead so we gybed back onto stbd. The wind has gradually filled in a little more, the skies have cleared and we're having a great sail now.
Hopefully we can stay in this current without having to gybe to and fro often. It will be well worth it if necessary though. Still waiting for the ITCZ to materialise!
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