There is a good chance that it's raining while you read this. You probably still have your heating turned up at least half way. The sky may look as though you are viewing it from inside a Tupperware box, and your coat and scarf may not be enough to keep out the late-March chill. But all the same, rejoice, for it is, officially, spring.
And how do I know this? I know because I have taken my socks off, and I shan't be putting them on again until November, regardless of what the weather may hold in the meantime. For me and my kind, it's Birkenstocks on until the snows come.
The annual jubilation that marks the clocks going forward by one hour is one of several signposts to spring that are, for the British, carved in stone. And the arbitrary nature of the dates involved only makes us cling to them all the more.
First is British Summer Time, during which anyone with Saxon blood is genetically obliged to drink a gin and tonic al fresco, whether or not there is a howling gale.
Next comes the Oxford vs Cambridge boat race, a traditional English spring rite in which we stand shivering in Putney to remind ourselves why it would not be a marvellous idea to take a year out and go back to university. This year, that coincides with Easter weekend, which is for walking in the countryside. Or on Tooting Common, if it comes to that – there are even places, apparently, where you can barely notice the dogging.
Finally, the Grand National the following Saturday marks the last blissful slide into summer. But this season on the brink of sunshine always seems to be the most delicious.
Outside of London, I am told, there are buds and green shoots and all manner of ludicrously fecund animal behaviour to indicate that winter is finally over.
At home in the Midlands, for example, my mum will be in the garden throwing stones at breeding toads, in a Sisyphean and ultimately thankless attempt to prevent the clumsy males from drowning the poor girls. In the city, on the other hand, we have to look for more subtle signals of the changing season. One is that we now have a morally-sound reason for kicking pigeons: just the male ones, mind, who in March are pests not only to us, but also to their pitiful, exhausted lady friends.
Those of us with an inch or two of outdoor space have a better window on nature than most. The astonished smile on the garden-centre owner's face when the fair-weather gardeners suddenly return en masse on the first sunny weekend of the year. The thrillingly pagan commitment ritual of a new boyfriend asking if he can plant his legumes in your freshly-dug vegetable patch. (The human female has better luck than her animal sisters in this respect, at least. And please don't worry, mum: when I say "planting his legumes" I mean only in a purely literal sense regarding broad beans.)
But the office-bound can also witness the effects of the almost imperceptible spring thaw. Tourists are walking (even) more slowly down Kensington High Street. The desk in front of the window is suddenly unbearably hot, rather than bone-chillingly cold. Starlings are nesting in the loft. The buggers.
Once spring tips into summer, it always seems to be over in a heady flash of ice cream and sunburn and pictures in the tabloids of girls in their bikinis all the way till school goes back. Which is why this tantalising turning point is so special. Just now, the year could still end up being all that you wished for.
There could yet be a satisfying election result; an end to the recession; honey still for tea. There could even be a long, hot summer. So enjoy this fleeting season of optimism while it lasts – after all, we've already just lost a whole hour of it.