When it isn't being remorselessly dull, British weather is just plain weird. When I left work on the train this evening, it was beautifully bright. The low sun and clear air made even the dowdiest buildings shine like jewels. Gradually, as I got closer to my station, the colour drained away and big, fat flakes of snow started to fall. By the time I got off the train, the sky was low and a soft dove grey and I walked into a swirl of dim whiteness. It was like stepping out of the wardrobe into Narnia.