When it comes to a stowaway showerproof jacket for warmer, wetter days, the Etxeondo Flux-Life ticks all the boxes.
It’s extremely light, it folds up into a jersey pocket and it held off the best efforts of a winter storm during testing. You can even do up the zip with heavy-duty gloves on.
You’re unlikely to encounter conditions like that from March onwards, even in Great Britain, but it’s nice to know you’d be OK if you did.
A trade-off for the low weight and pack size is the lack of elastication around the waist.
It does mean a bit of flapping around in the wind, although, on the other hand, this leaves jersey pockets within easy reach and the extra material did a good job of blocking splashes from the road.
Of course it won’t do the job of a winter coat, but if there is even the slightest chance of a drop of rain spoiling an otherwise dry day, then you wouldn’t really have any excuse to leave it at home.