sentences:  A complex weather system developed in mid-December, involving the merging of the remnants of Tropical Storm Olga with a cold front associated with a major winter storm to the north over the Northeast and Midwest.As a result, the first severe weather episode in more than a month in the US produced several tornadoes across the Deep South, particularly southern Georgia and northern and central Florida, late on December 15 and early on December 16.At least 12 tornadoes were reported across the region, with significant damage in several communities.