Checked the weather and it looks a bit warm at mid day, but I wouldn't cancel myself. We've shot scoters in t-shirts on the ocean and scoters and eiders in everything from 40 to 0 degree weather too. You'll be going out early in the AM I'm sure when it won't be super warm and the birds should be moving about at day break.
Have noticed that the OS in Barnegat aren't flying much in sunny weather this year but I think it's usually the wind that makes the real difference. The 29th forecast of rain changing to snow (at least where I found the weather) would be very desirable as it reduces visibility and forces the birds to look for sheltered area. I'm sure OSO knows how to deal with weather variables in their location and setup.
Would love to hunt with them but still don't have a firearms class certificate as I was grandfathered into a hunting lic long ago.
So I'd go whatever the weather, particularly as the sea duck season is short and winding down.
Just let us know how it turns out if you go.
"There can be no greater issue than that of conservation in this country." Theodore Roosevelt