Although certainly the computer planning program for weather depending on the pilot charts would be good for a South Pacific run and many trade wind passages, it does not replace real time weather planing--such as given by a number of services. These services depend somewhat on models--but also on examination of the meterologic data which is available. For example if a major front with squeezed isobars is heading across the high North Atlantic, or the Pacific High is displaced abnormally low--as it as during the Nordhavn 40's around the world voyage--it would not show up on the weather planing programs, but would on real time meterologic data. Obtaining the surface data, the various higher level pressures and winds aloft, and intregration of these into models will give much more accurate data for real world conditions which will be encounted and what adjustments maybe made for the route. I don't know if the weather planing material gives credance to the El Nino Effect, but we are in the end of an El Nino Cycle--and the currents and wind patterns will be affected in the S. Pacific by this. This may be more important for sailboats--but continual head winds and seas will take more fuel for power passagemakers. Bob Austin