Tropical Storm Colin – the third named storm of the Atlantic hurricane season – is expected to drench parts of South and North Carolina with heavy rainfall and possible flash flooding over Fourth of July weekend.

Tropical storm warnings were issued Saturday for parts of the South and North Carolina coasts. Tropical storm conditions could begin Saturday morning in South Carolina before spreading to North Carolina later Saturday through Sunday as the storm moves northeast along the shore, the National Hurricane center said. 

Both coastal South and North Carolina will likely see strong winds, heavy rainfall of up to 4 inches and localized areas of flash flooding through Sunday morning.

“There will be rough surf, dangerous rip currents and areas of coastal erosion in the vicinity of the storm this weekend,” AccuWeather meteorologist Adam Douty forecast.

As of 8 a.m. Saturday morning, Colin was located about 25 miles west-southwest of Myrtle Beach, South Carolina, with maximum sustained winds of about 40 mph. The storm was moving northeast at nearly 8 mph and is expected to dissipate over the western Atlantic on Monday, the hurricane center said.

TROPICAL STORM BONNIE:Bonnie forms in Caribbean, expected to hit Central America later Friday

Meanwhile, Tropical Storm Bonnie swept through parts of Nicaragua on Saturday, threatening flooding and heavy rain of up to 8 inches. Mudslides are also expected “to continue over portions of Nicaragua and Costa Rica” throughout Saturday, according to the hurricane center.

The storm made landfall Friday on Nicaragua’s Caribbean coast with maximum sustained winds of 50 mph before it began moving westward at 16 mph, headed toward Costa Rica. Bonnie is expected to move into the Pacific on Saturday before gaining power and likely reaching hurricane force by Monday.

Contributing: The Associated Press

Contact News Now Reporter Christine Fernando at cfernando@usatoday.com or follow her on Twitter at @christinetfern.