How this works: Each game's park factor combines three live effects. Wind is compared against the stadium's true compass orientation — so a 15 mph wind "blowing out" at Wrigley boosts home runs, while the same wind blowing in suppresses them. Altitude adds carry (Coors gets the biggest boost). Temperature affects ball flight — every 10°F above 70° adds roughly 2% to fly-ball distance. Numbers are shown relative to MLB average.