Alaphilippe Wins FAST Stage 3!

I wish I could describe what happened during today's third stage of the Tour de France.  But I wasn't able to watch it.  I bought the gold pass from NBC to watch the entire race, but the website was inaccessible from my office.  I'm not even able to access a replay, several hours after the stage ended.  There will be no screen captures in this post.  I'll have to get to a comparison between our prediction and the actual result, and then get to our prediction for tomorrow's stage.

Julian Alaphilippe won a very fast stage today, and in the process of doing so, secured the yellow jersey for France for at least tomorrow's stage.  Our prediction wasn't great.

• Stage 03:  4h 40' 29" (actual), 5h 06' 59" (prediction), 26' 30" slow (9.45% error)

The days of being happy to get a prediction error less than 10% are long gone.  We clearly missed something today.  After reading a few summaries of the stage, we learned that there were some rather strong tailwinds.  If someone watched the stage, please let me know if it looked as if winds helped riders.  I'm anxious to learn of other reasons, too.  Alaphilippe's average speed was certainly greater than what we thought on a fairly flat, but hilly near the end, stage.

• Stage 03:  12.78 m/s (45.99 kph or 28.58 mph)

Given how long the stage was, I'm shocked at that average speed.  It's 3 kph greater than even what the Tour de France's website thought might be an upper limit for the average speed.

Tomorrow's Stage 04 is classified as flat, though there are a couple of category-4 climbs in the latter half of the stage.  We thought tomorrow's stage would be faster than today's stage.  The 213.5-km (132.7-mi) stage commences in Reims.   Riders will head mostly east where they'll finish the stage in Nancy.  Our prediction is given below.

• Stage 04:  4h 42' 50" (prediction)

Are the cyclists outputting more power than we expected?  Are they and their bikes more aerodynamic than what we've ascertained from recent publications?  I don't know, and that's what makes this so much fun.  It's time to learn something!