Hi Nova
North Shore (and west shore) has advisories with N. Shore calling for waves of over 35 feet. The beach will be clearly marked as dangerous surf and even if there isn't a lifeguard posted in the immediate area they use little three wheelers to travel up and down the beach to make sure no one gets in ocean there.
Especially tourists who surprisingly will see a sign saying beach closed and assume it means that it's closed to everyone but them (haha).
The locals (military and college students...etc...anyone that lives here) pretty much observe the signs.
I haven't been here long enough to know if this is normal wave activity (N. shore gets high waves during winter and this is close to the end of the winter season here) or if this is caused by multiple earthquakes.
I haven't seen anything to indicate that it's from the activity in Japan so it might just be normal here (the pro surfers are still on island and that tells me the waves are still good this season KWIM?)
She should be fine, if anything comes up and it's a dire emergency she is welcome to come to my home. We can PM details if that happens Nova. I live in near the top of the volcanic ridge at a very high elevation.