Wind Talk

Thread starter #1
So I race Sunfish on a 60 acre L shaped lake that is at 1357ft. It is surrounded by 60 foot pine trees and cliffs that rise immediately on the right side of the starting line to 1425ft (not including the trees) and gradually to 1600ft on the other three sides. The airplane pilots say that the wind drops down off the cliffs. I'm well aware of the 3 winds described in the Sunfish Bible. Any comments on the "dropping wind" and how one would expect it to behave (center of lake vs along the same or opposite wall). Thanks!


Well-Known Member
Is the Sunfish Bible's "dropping wind" describing "katabatic winds"?

With about the same height difference of your land mass and trees, I rely on katabatic winds to get me home late in the day. The cooler temperatures of wooded areas bring a gentle flow down on the waters. Close to shore, I make decent progress using that "wind", but it's more like a cool draft.

Unless there's a strong breeze to affect it, I'd expect your lake's center to have "confused winds", :confused: and sometimes, none at all:(.
Thread starter #3
Thanks. We race at 2PM. The lake (which is pretty narrow) is probably a little cooler than the woods at that time. Sometimes it seems that the "heavier" air (>10mph) just bounces off the walls. This was a tough season. Very light & variable.
Thread starter #4
I figured out that it is an afternoon offshore expansion differential wind (created when the pressure levels above an elevated lake fail to rise as much as those above the surrounding heated lowlands; brings upper, higher velocity airflow in an overflowing gradient or expansion differential wind offshore onto the lake surface). Its a strong, gusty wind.


Active Member
Where is this lake located and does it have a name so I can find it on Google Earth? GPS coordinates? And what direction does this "strong, gusty wind" come from?

- Andy
Thread starter #6
Merriewold Lake in Sullivan County, NY. Gusty is a relative term to what was a light variable wind this summer. This afternoon, the wind was mainly NNW, then things went dead, and then the gust came out of the SE for a bit. The wind then reverted to NNW. The direction varies each weekend. Early in the season, when the lake is colder...I've seen this type of wind catch the novice sailors off guard and one of them always capsizes. It's a very small lake that freezes real nice in the winter for one of my slower iceboats (an Arrow).