CHARLESTON — A “critical” flash flood warning is in effect for Berkeley and Charleston counties the night of Oct. 4.

At 8:52 p.m., the National Weather Service issued the warning, which will remain in effect until 11 p.m.

“This is a dangerous and life-threatening situation,” the NSW warning stated. “Do not attempt to travel unless you are fleeing an area subject to flooding or under an evacuation order.”

The alert, which pinged cell phones across the area, came as rain pounded parts of the Lowcountry, including West Ashley, Mount Pleasant and downtown Charleston.

“Doppler radar indicated thunderstorms producing heavy rain across the warned area,” the warning read. “Between 2 and 4.5 inches of rain have fallen. Additional rainfall amounts of 1 to 3 inches are possible in the warned area. Flash flooding is ongoing or expected to begin shortly.”

The agency’s Charleston forecast for Oct. 4 showed showers all day, resulting in a proactive cancellation of two major local events.

Now North Charleston, Mount Pleasant, downtown Charleston, Daniel Island, James Island, West Ashley, Johns Island, Hollywood, Charleston Naval Complex and Charles Towne Landing might experience flash flooding, according to the warning.

When encountering flooded roads, the weather service is warning drives to turn around, as most flood deaths occur in vehicles.