Parts of Louisiana’s disastrous, ongoing flooding has been upgraded by meteorologists to once-in-1,000-years rainfall, with other areas classified as 500-year and 100-year events, nola.com reported Monday, as scientists warn that such storms are growing more and more frequent as the planet heats up. “On Tuesday, the National Oceanic and Atmospheric Administration (NOAA) is set to classify the Louisiana disaster as the eighth flood considered to be a once-in-every-500-years event to …