Power outages stretched into another day across northwest Indiana following what NIPSCO called “unprecedented” damage to the power grid from Tuesday’s derecho. As of 4 p.m. Friday, the utility reported 179,000 customers remained without power. Since the round of storms earlier this week, the company said it has restored electricity to 138,000 customers. NIPSCO estimates that more than 60% of its customers were impacted, making it the single-wors…