Go swimming in the lake this morning.
Then stand stand dripping wet outside for a half hour.
Go in the house and it will no longer feel cold to you.
But seriously, it's all about what you are accustomed to. (I know, bad grammar).
Consider the feeling one gets on a 54° day in February.
Compare that to the same weather in September.
Keep the thermostat low... lest Greta come get you!
