HARLINGEN — A flash flood watch is in effect today through this evening, forecasters say.

The National Weather Service in Brownsville has issued the watch for Inland Cameron, Inland Willacy, Hidalgo and Starr counties.

Slow-moving thunderstorms unleashing heavy rainfall of three to four inches in some locations are possible this afternoon. This morning, some areas could receive one to three inches of rain, too, saturating soil.

Forecasters say be on the alert for heavy bursts of rainfall causing small streams and arroyos to flood across Deep South Texas. Low-lying areas with poor drainage could see widespread street flooding with water depths rising to a foot or more in some areas.