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 Co.

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

By 5:30 a.m. Tuesday, the total number of outages in CMP’s 11-county service area had fallen to just under 1,700, with 179 customers reported without power in Cape Elizabeth, 340 in Harpswell and 240 in Boothbay.

Alison Leavitt clutches an umbrella against the heavy rain as she enters One City Center in Portland for a workout at the gym on Monday.

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.

The storm is also likely to overwhelm Portland’s combined sewer and storm drain system. Portland’s sewers typically overflow into Casco Bay whenever the city receives more than 0.5 inches of rain.

24-hour rainfall total in #PortlandME: 2.41". Sewer overflows into Casco Bay are likely, based on past experience.

— Casco Bay Sewer Overflow Alerts (@CascoBayBot) April 17, 2018

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.

This story was corrected on Tuesday, April 17 at 3:50 p.m. A previous version incorrectly attributed the “Casco Bay Sewer Overflow Alert” Twitter account to the City of Portland.