How much change in boil-off from winter to summer

I have noticed that in the dead of winter (0 degrees F) I tend to boil off almost 2 gallons. I just brewed today which it is 25 degrees today, and I notice I have about a quarter gallon extra wort than I was thinking at the end. I have been almost spot on my last couple brews with boil off, but those have all been around 0-10 degree days, so this was weird today.

What do you guys generally experience for a changing boil-off rate from winter to summer?

I have never really noticed a difference, but the weather here never really drops below 45-50 in the dead of winter

Less than a quarter gallon difference here, but I'm in temperate CA.