My friend Webb and I had the pleasure of doing an Alcatraz Swim with Gary Emich last December.  The water temp was around 51 and to the best of my recollection the air temp was around 45.  But, unlike the day described in the attached article, the San Francisco Bay was relatively flat and it was a bright, sunny morning!

I hope you enjoy Gary’s article as much as I did!

http://adventuresportsjournal.com/racing/alcatraz-swimming-society