The National Weather Service has issued a flash flood watch that includes Genesee and Monroe counties that will be in effect from late tonight through Saturday morning.

The watch also includes Niagara and northern Erie counties.

Localized rainfall in excess of one inch is possible in the watch area, the Weather Service said.

Hardened ground because the recent dry weather combined with less efficient urban drainage will combine to cause higher potential for flash flooding, the Weather Service said..

A flash flood Watch means the threat of flash flooding exists along rivers and creeks.

Be ready to move to higher ground if flooding is observed or a warning is issued.

There is a risk that thunderstorms will produce strong gusty winds, and heavy downpours, which could cause flooding late tonight across the region, according to the Weather Service.

Livingston, Orleans, Wyoming, Allegany, Cattaraugus and Ontario counties are among areas that could be affected by the thunderstorms, though no watches or warnings had been issued for those counties as of 2 p.m.

There’s also a risk Saturday morning that thunderstorms will produce strong gusty winds, and heavy downpours which could cause flooding, the Weather Service said.

Here’s a forecast for the Genesee region from the National Weather Service:

This Afternoon

Sunny, with a high near 80. West wind around 14 mph.

Tonight

A slight chance of showers before 3am, then a chance of showers and thunderstorms between 3am and 5am, then showers likely and possibly a thunderstorm after 5am. Increasing clouds, with a low around 64. South wind around 8 mph. Chance of precipitation is 60%. New rainfall amounts between a quarter and half of an inch possible.

Saturday

Showers and possibly a thunderstorm, mainly before 1pm, then a chance of showers and thunderstorms after 1pm. Some of the storms could produce gusty winds and heavy rain. High near 77. West wind 8 to 18 mph, with gusts as high as 29 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.

Saturday Night

A chance of showers and thunderstorms before 7pm, then a slight chance of showers. Mostly cloudy, with a low around 64. West wind 8 to 13 mph. Chance of precipitation is 30%. New precipitation amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

Sunday

Mostly sunny, with a high near 80. West wind 7 to 10 mph.

Sunday Night

Partly cloudy, with a low around 61.

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