Apricity
It's hard to beat the feeling of the warmth of the winter sun on your face. There's a word for it too: apricity. Uplifting, hopeful, calming — even a few short moments to bask in an unexpected, weak but glorious gleam of winter sunlight is wonderful.
A brief burst of apricity warms the spirits and your skin. It reminds me of distant warm, long, summer days, and the promise of spring in a few months. If it has been bleak and cold, apricity is that much more welcome.
From the UK's position in the Northern hemisphere, with the sun low on the horizon, you can let the sun hit full in your face in the middle of the day without craning your neck or leaning back. It's never too hot to seek shade, and often just the right brightness that facing it dead on with your eyes closed is ideal. Together with the long shadows of winter, the effect can have you swept up with the rays, letting them soak into your skin and transporting you away from the cold under your feet.
From the latin aprico, 'to warm in the sun', and in turn aperio, 'lying open', it has been around since at least 1623 . It feels to me like we'd benefit from its resurgence.