Some parts of Florida could melt century-old readings.

A flood watch was issued for South Florida on Tuesday as a week’s worth of rain moves into the region. The watch, which covers Miami-Dade, Broward and Palm Beach counties, is in effect until 10 p.m.

When meteorologist Jim Cantore starts posting, weather-watchers pay attention. When he visits, it’s even worse. You’re in the path of a hurricane. We’re still about two months from hurricane season, ...