Another good prediction of the surf conditions is from the National Data Buoy Center.  The data is a little complicated to interpret so an image is included.  High waves are worse for a pounding surf.  A pounding surf scares the critters down in the sand and prevent the clams from showing.  The image shows that on 2/10/2017 at 9:50 a.m. the wave height is 19.7 feet. and on 2/11/2017 at 8:50 am the wave height was 7.8 feet.  Which means the waves were pounding on 2/10 and far less intense on 2/11 and therefore much more conducive to clam digging.

Key to understanding the waves is height and frequency.  Nine foot waves every nine sconds are terrible.  Three foot waves every twelve seconds are way better, especially for boating.  A one to one ratio 9 feet high every 9 seconds or 6 feet high every 6 seconds are worse.  It is the cycle between the waves that is important.

Mouse click the image to pop out in readable big size.

Current Roosevelt Beach Tide Trends - 5 day

Embedded link to the Roosevelt Beach Buoy.