An early spring storm packing heavy rain and powerful wind gusts caused widespread power outages and flooded roads throughout southern Maine on Monday.

More than 9,000 customers of Central Maine Power were without power late Monday night, with the largest concentrations in Gorham, Harpswell and Phippsburg, according to Central Maine Power.

As of 9:13 p.m., Gorham was reporting the most outages with 2,291. Phippsburg had 2,021 outrages and Harpswell reported 934.

The National Weather Service in Gray issued a flood advisory Monday afternoon for most of southern Maine, warning that heavy rain could cause small creeks and streams to flood onto streets, highways and underpasses. The weather service reported heavy rainfall amounts throughout the region Monday with Scarborough getting 1.7 inches, Cumberland 1.6 inches and Buxton 1.5 inches.

It was raining so hard in Portland on Monday night that the city of Portland tweeted that sewer overflows into Casco Bay “are likely, based on past experience.”

Portland, South Portland, Brunswick, Westbrook and Augusta were among the cities and towns that were expected to experience flooding during the night.

Chris Kimble, a meteorologist with the National Weather Service, said coastal regions received heavy rain while inland areas saw some icing and light snow.

Wind gusts reached 52 mph at the Portland International Jetport and 40 mph in Cape Elizabeth, according to the weather service. A wind gust of 57 mph was reported in South Bristol in Lincoln County.

The weather service said the heavy rain and wind should subside early Tuesday morning, with the forecast calling for cloudy skies and highs in the upper 40s in Portland on Tuesday.