Flash Flood in Onondaga County, New York

The county reported permanent damage to over 250 roads in the county, with most of the damage centered on the Syracuse area. Several roads were totally washed out, and the City of Syracuse described the urban flash flooding as major. Most roads in the county experienced degrees of flooding from ponding to major flooding and roadway breakdown. Standing water remained and closed several road intersections for several days afterward.

A slow moving warm front pushed northward across central New York late in the afternoon on April 25th. A warm and relatively moist air mass covered the region, with showers and storms developing, especially in the unstable air south of the frontal boundary, where breaks in the cloud cover allowed temperatures to rise to near 70 degrees. Severe weather developed, and in addition to reports of severe wind damage and hail, plenty of wind shear in the vicinity of the warm front allowed for a few super-cell thunderstorms and tornadoes to develop. In addition, areas of heavy rain caused significant flash flooding in several locations of central New York.