Summer tires in Winter

[kk2002s]

Just bought 2002 Boxster S as my daily. It has very new Sumitomo HTR Z III all around. I have read the perils of driving Summer tires in the Winter (Live in NJ) but I am in no position after purchase to get winter tires. I may be able to use another car for some colder, snowy day but for the most part I have to get to work which is only 12 mile one way, 2/3 on hwy. So if it 20 - 30 will these tires get damaged for next summer? Next year if the tires are still in good shape I'll consider Winters or all seasons but this winter leaves little wiggle room