BRally

BRally
BRally - Europe or Africa to Angra dos Reis

2012/01/02

Winds and Currents of Brazil:





The coast of Brazil is divided into North Coast (5S and above), East Coast (5S – 23S), and South Coast  (bellow 23S).

On the North and East Coast the predominant winds are in the range of 10 to 15 knots, from NE, E and SE, where the NE and E are predominant in the summer, and the SE in the winter.  On the North Coast, rain is more common during the summer, whereas in the East Coast rain is during the winter.

Bellow 20S, the predominant winds are NE and N, changing in the winter to SE, S and SW. During the winter, it is common to have the cold fronts coming from the South, bringing colder temperatures and some gusts.  The cold front is noticeable because there will be a sudden raise in the air pressure, a change in temperature, becoming colder, some rain and thundering, with the wind turning  from NE to NW and then SW, when gusts are noticeable.  The darker clouds coming rapidly from the SW are a good sign of an incoming cold front. A cold front will remain between 2 to 3 days. Generally, the faster  the change, the smaller the time.
Rain is evenly distributed amongst the seasons, with higher intensity around 23S, moderate around 23S, and rare more to the South.

The seasons in Brazil follow the Southern Hemisphere seasons, Summer during Dec/21 and Mar20, Autumn during Mar/21 and Jun/20, Winter during Jun/21 and Sep/20, and Spring during Sep/21 and Dec/20.

Along all the Brazilian Coast it is common during the night the presence of a wind coming from the land side, called “Terral”. Boats sailing closer to shore will notice the change from the predominant wind to the Terral. This is most perceptive bellow lat 23S, where the coast arches to West and where the predominant wind is less noticeable.

On the North Coast, the ITCZ is seldom noticeable in the winter and is generally located between 0 and 10N, but will affect boats crossing to the Caribbean on that season. In the summer it moves 5° more to the South, thus promoting some changes to sailing the North Coast during the that season.

There are no Sailmail stations close to Brazil, being Africa and Panama the ones more likely to be reached for the receipt of GRIB files and emails.

The current affecting the East Brazilian coast come North from South Africa (Bengal), goes West crossing the Atlantic, and divides North/South on 7S 32W in the summer, and 16S 37W in the winter.  The Southern portion of that current is called Current Brazil. The average speed of the Brazil Current  close to the Brazilian coast is up to 2k during the Summer, and up to 1k during the Winter. Stronger NE winds can increase the intensity of the current, that can be present up to 200 miles from the coast.

On the North Coast, the current is always NW.

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