As long as your companionway boards are in place & locked then the tide may get seawater in between them, but she should right herself. Also remember to close any portholes or overhead hatches as well. The other areas she can take on water is from the cockpit hatches & anchor locker if the boat is heavily heeled over. But the biggest risk of damage is not from water flooding in, but from your exposed rudder. As the boat heels the weight of the hull will rest mostly on the side of the keel & hull, but if an excessive amount of weight shifts aft, then the rudder shaft & tube will bend & the rudder will be severely damaged. I've seen a couple of badly grounded boats on dry dock where the rudder was permanently bent outwards about 30 degrees. A boat is always most vulnerable to damage at the rudder, which is an expensive fix.
