Heavy rains and snow will pound the eastern United States into Monday, possibly leading to downed trees, power outages and flight delays as a low pressure system from the Gulf of Mexico moves through the region. Intense precipitation from the Nor'easter storm started Sunday morning, with two to four inches of downpour expected along the Mid-Atlantic Coast, which will make for soggy conditions in New York, Philadelphia and Washington, D.C. -- Reported by msnbc.com and news services Follow @msnbc_pictures