A flash flood watch for parts of southern Erie, Cattaraugus, Chautauqua and Wyoming counties will remain in effect until 11 p.m. tonight, according to the National Weather Service.
Slow-moving showers and thunderstorms will bring heavy rain to some locations after 5 p.m., but amounts are expected to vary significantly by location, the weather service reported.
New rainfall amounts between a quarter and half of an inch are possible.
A flash flood means the threat of flash flooding exists along rivers and creeks. Areas with steep terrain tend to be the most vulnerable to flooding, but it’s not clear how this storm will play out.
“There could be a lot of rain anyplace where the cells pop up, and it’s difficult to pinpoint exactly where that will happen,” said meteorologist Jim Mitchell.
He said the potential for flooding is also increased because of the slow-moving nature of this storm system.
On Sunday, the weather service calls for a chance of showers and thunderstorms, with mostly cloudy conditions in the Souther Tier and partly sunny skies in Buffalo. A high temperature near 76 is forecast.