Out and out wet weather tyres

I have never heard of a tyre being marketed purely as a wet-weather specialist, probably because the huge majority of buyers won't or can't keep swapping their wheels to match today's weather. But many tyres are suitable for extended racing with all the major brands, and a few smaller companies, offering high-end rubber. Almost without exception they will give good grip in the rain, by which I mean good grip for the tiny size of the contact patch.
That nice Mr Google provides a long list of reviews so you can read some relatively unbiased opinions about hundreds of tyres. I always ignore the fairy stories told by friends and acquaintances, people only recommend what they have just bought and tales of a million miles without a single puncture soon begin to pall.
Best of luck.

Rode all winter (over 1000 miles) on 25mm Continental GP 4-Season's and they gave me excellent traction, especially cornering, even with wet cobbles and brick. Got my first flat on them at 1400 miles from an industrial staple. The roads I ride are urban with lots of glass and rough tarmac. Currently using 25mm Vredestein Senso All Weather's as they were on sale and are supposed to have good performance in cold, wet conditions but we've been having a series of heat waves so can't comment on their wet weather traction yet.

I find my Open Paves fine on the winter bike in all weathers.
Though so were my open corsas (25)on Sundays 70 in the wet.