To those commenting on the times, or the 100th times, keep in mind that the marathon does not have pacers and it is up to the elites to set the pace themselves. And this year, like 2012, had to combat the olympic trials which took out a lot of top american runners. 2008 trials were the day before NY marathon in 2007, so less effect then. And 2007 was the year of the fierce storm.
Monday morning, standing in Hopkinton, there was a slight breeze, at best, in the face. But it was faint and almost non-existant. Standing in the shade compared to the sun was night and day different in terms of overall feeling. The sun was VERY powerful. We did not have any day with this kind of temperature or sun power at all in 2016 in the Boston area. There was no way to train for a day like this if you lived in Boston, without running on a treadmill, under a heat lamp.
The first 10 or so miles were run with a faint headwind. It was barely noticeable. And it was dry.
In Wellesley, the breeze picked up slightly and felt refreshing to some extent.
In Newton, it remained 'refreshing' until about mile 19 or 20. Then the headwind became a bit more noticeable and increasingly resistant.
By the time we were at 22 and then making the turn onto Beacon, it was a powerful headwind that just slowed you down. It probably cost me about 10 seconds a mile going down Beacon.
Overall, the key to running was to start off conservatively from your goal. About 5-10 seconds slower per mile. And to just drink water/gatorade early and often. I do not think people truly appreciated the conditions until they were at 10K or so. But by then, it was too late. And this happens every now and then. I think this year was slightly easier than 2014 because it was dry and not humid. It was certainly easier than 2012, which was ridiculous, and easier than 2005, 2004, and 2003, which were also hot and humid years.
The general consensus seems to be that it was also harder than last year with the wind and rain.