I tried the iwindsurf site and seems to be working fine on my computer. Might check to see if your 'pop up blocker' is on which could make it not work.

I use windfinder.com and iwindsurf to compare what they are forecasting and then average the two. IMO windfinder.com is the most accurate. Any site is only good out to about 48 hrs even if they list a 5 -10 day 'outlook'.