A tropical disturbance has triggered a flash flood emergency across much of southern Florida, with residents bracing for further intense rainfall on Thursday and Friday. In the last 48 hours, some areas have received up to 20 inches of rain. The severe weather has led to flight cancellations at Miami International Airport and road closures, including parts of major highways, coinciding with the early start of the hurricane season and a storm system moving across Florida from the Gulf of Mexico.