Water temps are mid 60's, a kayaking wetsuit will be just fine. And the air temps are typically very comfortable this time of year. Check here for forcast. These guys seem to get it right more often than many of the other websites. It looks like the wind is even going to co-operate more or less. That's saying something here in The Gorge.
Living life like there's no tomorrow.
http://gorgebikefitter.com/
2007 Look Dura Ace
2010 Custom Tonic cross with discs, SRAM
2012 Moots YBB 2 x 10 Shimano XTR
2014 Soma B-Side SS