Could the weather gods in Scotland deny Jordan Spieth a Grand Slam?

"I'm not a fan of tournaments where the outcome is predicted so much by the weather. It's not my sort of golf."

Those words were spoken by Rory McIlroy in 2011, after a very forgettable weekend at the British Open that saw him fall to 25th place. Raw as these sentiments were, he did not repeat them at the 2014 Open, when he benefited from favorable conditions to win his first claret jug at Royal Liverpool. That year, the Thursday afternoon/Friday morning wave got the short end of the stick, battling wind and rain while their counterparts made it through 36 holes unscathed. Heading into the weekend, 17 of the top 20 players had played on Thursday morning and Friday afternoon, including ten of the top 11. Among that lucky group, of course, was Rory.

The fact that he benefited from the same phenomenon that sunk him in 2011 doesn't detract from the overall point. At the British, fluctuating conditions can make winning impossible for up to half of the field. The R&A tries to mitigate the imbalance by flipping the start times—if you tee off in the morning one day, you play the afternoon the next—but the weather doesn't always obey a strict daily schedule. The 2014 situation was an extreme example of how things can flip, but all it really takes is one morning or afternoon of torrential wind and rain to handicap a significant chunk of contenders, and to give the rest an incredible boon.

According to initial forecasts, that scenario seems likely to play out at St. Andrews this year. Check out the R&A prognosis in the photo below, released this morning:

As you see, the huge red flag here is Friday. The idea is that it's going to rain heavily overnight, and despite the "cloudy and damp" start to the morning, the course will likely play soft and slow, which means low scores for the morning wave. By the time the afternoon comes, conditions will be drier, and—here's the problem—winds will increase to 35 mph. That could mean absolute murder for the afternoon wave, and heavy winds on Saturday morning that die off by midday could further separate the players at the top from those giving chase. In cases like these, the slightest chasm can grow unbearably wide with just a few hours of nasty weather—imagine half the field crossing a long bridge, and then burning it down with the others still waiting on the far side.

So who does it hurt? As the tee sheet shows, there's no shortage of big names that will have to contend with the wind on Friday afternoon. They include: Jordan Spieth, Tiger Woods, Graeme McDowell, Bubba Watson (if he thought "water on the clubface" was bad, I can't wait for his reaction to this...), Dustin Johnson, Jason Day, Ian Poulter, Billy Horschel, and 2010 St. Andrews champion Louis Oosthuizen.

On the flip side, the following stars will tee off on Friday morning: Zach Johnson, Adam Scott (one of the three players who struggled his way into Friday's top 20 despite the bad side of the draw at Hoylake), Martin Kaymer, Jimmy Walker, Phil Mickelson, Henrik Stenson, Matt Kuchar, Jim Furyk, Justin Rose (like Scott, another Friday top 20 at Hoylake from the wrong side of the draw), and Scottish Open champion Rickie Fowler.

It's important to note that wind direction, a far less predictable force, could also play a big factor. As Justin Rose noted in his press conference this morning, a course like St. Andrews—where the front nine is a true "outward" nine, in the sense that the holes all go in the same direction, and the back nine turn inward—opens the possibility that a player could face a headwind for 18 holes if the wind direction changes after nine, which could be far more critical than pure wind speed.

"The draw is a funny thing, especially at an Open Championship," Rose said, when I asked him about the vagaries of fate. "It can make things lopsided...you just hope over the course of a career that that evens itself out. But I'd say the last five years I've been on the wrong side of things, but I was looking forward to maybe lady luck turning and going my way this year, so we'll see."

As it stands now, the clear advantage belongs to those who will be warm and toasty on Friday afternoon, and the biggest obstacle to a Spieth grand slam might be the one thing he can't control. If you're in Scotland, you may want to keep this in mind when you visit your local Ladbrokes shop...