Me... I tend to be so much more exploratory in the warmer months.
maybe its the weather, or the lack of clothing to begin with. the fact we are already hot and bothered.  
we seem to be stripping more in the summer. Skinny dippin pool parties beach days bike rides seems to be loads of chance encounters. more so than in the dead of winter.
I love playin outdoors when ever the opportunity presents itself and in the summer it seems to be more avail to us.

Definitely winter.  There's nothing like the anticipation of unbundling layers of clothing in a nicely warmed bedroom, watching your companion do the same, and then sliding beneath sheets and being further warmed up by bare skin against bare skin.

I have to agree with you Nic however, I have been keeping myself warm lately. There's nothing like taking a summertime walk in the woods looking for the right stump or rock to bend you over or maybe lay a blanket in a pine patch for some cool refreshing 69. I love that smell!!

... When it comes to sex, there IS NO OFF-SEASON!  Just do it!  

I use to have a pool, something about booze and bikinis go perfect togeth

And winter is depressing and geez, I hate being cold....  Hey sex on the beach is an idea...  ))  

For me its either spring or fall. Not too hot or too cold. Ride the kangamangus with a bottle of wine and a blanket in the saddle bag and pull over somewhere and walk into the woods.

Agreed. I especially love the Fall time. There's something about going out into the woods, smelling the freshly fallen leaves, and getting ravaged with mud and leaves in your hair ; - ). Reminds me of when I was younger...