Severe thunderstorms raking through the region Thursday afternoon caused power outages that were mainly confined to the Merrillville and Crown Point areas. NIPSCO reported over 7,000 customers without power in Merrillville, 3,261 in Schererville and 3,051 customers affected in Crown Point. High winds reportedly toppled trees causing 73^rd street to be closed off between Mississippi and Colorado Streets around 4:30 p.m.Thursday. The storm may have also contributed to a semi-rollover accident that tied up the northbound lanes of I-65 near 61^st Avenue for several hours. The National Weather Service let the severe thunderstorm warning expire early as the storm virtually fell apart after leaving the Merrillville area.