Could it be related to warmer weather?

Definitely worse in cold, but it's noticeably better than last summer and fall as well. Admittedly, the car hadn't worn in much then. Seems like it's even a lot better than spring was, and today wasn't very warm. It's a welcome change, whatever the cause!

I tried coasting the whole way today on the long downhill stretch next to my house (there's a small uphill partway) and I made it! Got down to 17 mph, which is a lot slower than my old vehicles, but still it's good to know I can do it. Since you can see behind you a long way I can tell if it's safe to slow down that much.

Maybe someone mentioned this in a response, but I couldn't find it...have you made note of the wind direction when you have tried coasting? I have a hill I sometimes coast down when I am going home from work. If I have a tail wind, I'm usually going about 65 mph or better. If no wind I go down a little way then have to shift back into gear. If I have a headwind I slow down right now!

Nice thing about this hill is...at the start there are a bunch of wind turbines. I can look at them and tell the wind direction, and whether I can coast or not.

Since my reference hill is the stretch I start out on for 95+% of my trips, I've had plenty of opportunity to try it without wind (today was calm, BTW). Good thought, though. Neat trick using the wind turbines. A lot of people complain about them aesthetically, but I like 'em!