Bass Pro in Clarksville has some thin synthetic gloves in the Archery or hunting department. Very thin and tight fitting. different models have different size bumps on the outside. The smallest is very small. I would guess they would be a big help down to about 30 degrees. Keep a couple of those heater packs in your coat pocket to warm your hands occasionally.

Haven't used mine yet but have used similar in the past and can cast spinning and baitcaster. Thumb may wear out if baitcasting.

Peter