The NEXT Weather team is issuing a NEXT Weather Alert Day for Monday as heavy rain starts to fall across South Florida.
Sunday afternoon, pop-up rain storms start to build across the Miami and Fort Lauderdale area.
CBS News Miami 
A tropical trough moving across the Florida Peninsula will move into the northern Gulf over the next two days. The National Hurricane Center says there’s a 20 percent chance of development in the next week.
As the trough moves, it will pull tropical moisture across the state, leading to significant rainfall in southeast Florida. We could see up to 2 inches of rain per hour during storms on Monday, with localized accumulations of up to 3-4 inches.
CBS News Miami 
The NEXT Weather Alert Day on Monday is due to the flash flooding threat associated with the heavy rain. The Weather Prediction Center issued a Level 2 (out of 4) Flash Flood Advisory for all of South Florida on Monday.
The rainstorms on Sunday kick off several days of rain stretching through Thursday.
