Ground the coax before it comes into your house.

Also run a ground wire from the mast directly down to ground and put a
ground rod there.

Also run a wire from the ground rod to the ground of your electrical
panel.

The lightning WILL get to ground, one way or another. The idea is to
give it another path that does not involve your house or radios.
Also ask on rec.radio.amateur.antenna


73's
Mark