After several days of warm and muggy conditions, people in the Twin Tiers were advised to be prepared for the possibility of flash flooding with the potential for torrential rainfall in parts of the region.

The National Weather Service at Binghamton has posted a flash flood watch for much of upstate New York and northeastern Pennsylvania.

New York counties included in the flood watch area are Broome, Chemung, Chenango, Cortland, Delaware, Madison, Oneida, Onondaga, Otsego, Schuyler, Seneca, Steuben, Tioga and Tompkins.

Pennsylvania counties under the flood watch include Bradford, Susquehanna, Wayne and Wyoming.

Localized rainfall amounts of three to four inches and potentially greater are possible, especially across parts of the Catskills and upper Susquehanna Valley region.

Forecasters expect localized flash flooding along smaller creeks and streams and some highly urbanized areas.

Most rivers are expected to stay within their banks but officials say they'll be closely monitoring them.