SAN FRANCISCO (CBS SF) — A thick, misty layer of fog draped over San Francisco’s TPC Harding Park Golf Course Wednesday morning. For most San Franciscans it was a pretty typical start to an August day, but for the best golfers in the world in town for the PGA Championship, it was a sign of conditions to come.

After several weeks playing in hot, humid weather back east, the PGA Tour pros are confronted with the conditions that normally baffle late summer tourists and fuel the sales of sweatshirts in the shops on Fisherman’s Wharf.

Few of the pros have the local knowledge of Tiger Woods, who played collegiately at Stanford.

“For me, when it’s cooler like this, it’s important to make sure my (body) core stays warm,” Woods said. “I know that I won’t have the same range of motion that I would have back home in Florida where it’s 95 every day. That’s just the way it is.”

“Talking with some of the guys yesterday, they were laughing at their trackman numbers already,” he added. “(They don’t) have the swing speed and ball speed they did last week. It’s (the course) going to be playing longer.”

The TPC Harding course is listed at 7,251 yards, but the mist, fog, wind and heavy air will make it play longer.

“It’s heavy air,” Woods said. “Whether the wind blows or not the ball still won’t fly very far here. I known that for all the years and times I’ve had to qualify (while being an amateur) up in this area. Marine layer, cool and windy — we are all going to have to deal with it.”

It’s an opinion shared by Jordan Spieth, who is chasing pro golf’s Grand Slam at the PGA Championship.

“I was anywhere from 10-13 yards shorter with a very similar swing and ball speeds through the irons,” he said. “The driver is up to 20 shorter in carry and that’s normalize on the trackman. So it’s very different.”

Spieth has been doing some on-course expermentation during the practice rounds.

“I’ve played nine holes each day already so I’ve seen the golf course,” he said. “I would say it’s been harder for me to hit, to commit to some of the clubs the first time around. I’m glad I have been able to play some holes and hit into the crosswinds and into the wind and see how much of an effect it really has.”

Spieth said he was also relying on memories of playing at the AT&T in Pebble Beach over the last few years.

“I’m used to playing the AT&T every year at Pebble Beach in February and we get very similar conditions to this,” he said. “So it’s an adjustment. I think for me, it normally takes a day or two and really being out on the course, hitting a shot. Being like – ‘wow’ – then hitting another one from the fairway and it still comes up short. Then you start to recalibrate.”

Justin Thomas, who won last week in Memphis and could become No. 1 in the world rankings with a win or high placing this week, is of a similar mindset.

“It’s like — hey, it’s pretty cold here and we’re playing in a bit of a mist,” he said. “There is probably a 15- to 20-yard difference.”

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