I've just noted that the latest beta version of SailMail (aka AirMail)
supports ROTFS GRIB files. These provide predictions for the Gulf Stream
and other currents showing the direction, rate and temperature for up to 72
hours in advance.
I don't quite understand their current speed predictions as they seem too
low, but at least it shows the relative speed and direction.
I placed a JPEG image of the GRIB display on my web site:
http://www.geoffschultz.org/Temp/rotfs.jpg
-- Geoff
www.GeoffSchultz.org