* WHAT. Flash flooding caused by excessive rainfall is possible. * WHERE. Portions of central and western New York, including the following counties, in central New York, Lewis, Northern Cayuga and Oswego. In western New York, Allegany, Livingston, Monroe, Ontario and Wayne. * WHEN. From 11 AM EDT this morning through late tonight. * IMPACTS. Excessive runoff may result in flooding of rivers, creeks, streams, and other low-lying and flood-prone locations. * ADDITIONAL DETAILS. - A slow moving cold front will approach Western and North Central New York today. Showers and thunderstorms will develop across the region. Locally heavy rainfall is possible with rainfall rates near, or exceeding 1" per hour at times. Repeated storms over any given location will have the potential to lead to poor drainage flooding and Flash Flooding. - http://www.weather.gov/safety/flood