Tropical storm warning for NC coast as system may become storm Copyright by WNCN - All rights reserved Video

RALEIGH, N.C. (WNCN) -- A Tropical Storm Warning has been issued for portions of the North Carolina coast as a system south of Charleston is expected to develop into a tropical storm, forecasters say.

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The warning is in effect from Surf City to Duck.

The watches are being issued for potential Tropical Cyclone Ten which is about 20 miles south southwest of Charleston as of Monday night

The cyclone has 40 mph winds with gusts to 43 mph and is moving north-northeast at about 7 mph.

Forecasters had expected it would already develop into Tropical Storm Irma, but it has not.

"Emergency planning should include a reasonable threat for tropical storm force wind of 39 to 57 mph," weather forecasters said.

Rainfall prediction models show more than 6 inches of rain are possible near Charleston, South Carolina with areas of more than 3 inches along the North Carolina coast.

A slow and erratic motion is forecast through early Monday, followed by a faster northeastward motion Monday night and Tuesday, the National Hurricane Center said.

On the forecast track, the system will move near the Georgia and South Carolina coasts Sunday night and Monday and move along the North Carolina coast Monday night and Tuesday.

A Tropical Storm Watch means that tropical storm conditions are possible within the next 24 to 36 hours.