When winds are from the N, NE, or E, a good rule of thumb is....Forecast waves 2ft or less = 1-3's. forecast 1-3= 2-4ft, forecast 2-4= 3-5's. The waves have a lot of water to build upon when wind is from any of those directions and a computer generated wave forecast goes on speed only without taking into consideration direction. I have found windfinder to be the most accurate but I check at least 3 different sites and compare. I also use the South Bass or Put In Bay location.