Slow-moving thunderstorms could dump 2 or more inches of rain on Palm Harbor and Dunedin between 4 and 8 p.m. Wednesday. The downpours raise the risk of flooded roads and standing water in low-lying neighborhoods.

Heavy rain expected Wednesday evening

10 Tampa Bay News (WTSP) issued a Weather Impact Alert for the Tampa Bay area covering that four-hour window. Tropical moisture is fueling the storms, and some will move slowly enough to drop heavy rain over the same spots repeatedly.

The biggest concern is ponding on roads and flooding in areas with poor drainage, according to the alert. Several small rivers across the Tampa Bay region are already at or near bank stage, and additional rainfall could push them higher.

Storms are expected to develop inland during the afternoon before drifting toward the coast during the evening.

Wet pattern extends into next week

Wednesday's storms are not a one-day event.

WTSP meteorologist Colleen Campbell wrote Wednesday: "The wet pattern won't end after today. Scattered to numerous showers and thunderstorms will continue through the weekend and into early next week, with the potential for additional heavy rainfall."

Repeated rounds of rain could compound flooding risk, especially in areas hit by multiple downpours. The afternoon and evening will carry the highest rain chances each day, particularly across the Tampa Bay area and points south into Southwest Florida.

Flood warnings spread across Tampa Bay

Pinellas County was under a flood advisory Tuesday during the afternoon, one day before the broader Weather Impact Alert took effect. The National Weather Service also issued a flood warning Wednesday morning for neighboring Hillsborough County, in effect from Friday through Saturday morning, according to the Tampa Bay Times.

No Pinellas County Emergency Management statement specific to Wednesday's storms had been released as of Wednesday morning.

How to stay safe during flooding

The National Weather Service warns that as little as 12 inches of rapidly flowing water can carry away most vehicles. 6 inches of swiftly moving water can knock a person off their feet.

WTSP's alert urged residents to keep weather alerts turned on, carry rain gear and avoid driving through flooded roadways.