Oh it might sound weird catching tailwinds from two directions. Here is the explanation and it has to due with wine AVAs: The Petaluma Gap vinicultural area first blows east from the sea, cooling grapes in the afternoon, then it splits mostly north and south. It is know for its Pino. The Carneros AVA gets it cooling wind off the north bay, blowing north to that auto parts store, Napa. Both AVAs touch Sonoma Mountain. Los Carneros is known for its Chardonnet. So, that is how you get tail winds in two directions while cycling through vineyards.