Favorable Wind spell help

[Hamiloin]

My party just boarded a ship sailing with approx 30 mph winds and the druid cast Favorable Wind into the sails which creates a 30 mph gust of wind. The question at the table was whether or not the ship would go any faster, and if so, how much faster. Any thoughts?

[VoxRationis]

If the wind speed is 60 mph in a sudden gust, what's going to happen is that it will damage the rigging and the ship will have to slow down or stop while the sailors make repairs.

[eggynack]

I don't think it would increase speed, no. You just get a 30 ft. wind, and that doesn't get added on to any preexisting wind conditions. If you want evidence of that, check out control winds (http://www.d20srd.org/srd/spells/controlWinds.htm), which does have language that indicates the ability to increase wind speed from some base level, unlike favorable wind which just grants one static speed.