Hurricane Harvey will make landfall near Corpus Christi, Texas late Friday or early Saturday, unleashing “devastating” and “life-threatening” flash flooding, according to the National Weather Service, combined with up to 120 mile per hour winds.
And the rain potential of the predicted Category 3 storm in particular is raising alarm, with the former head of the American Meteorological Society fearing an “epic flood catastrophe,” according to The Washington Post.
It’s even forced forecasters to rethink their rainfall maps. When Harvey hits, it's expected to unleash so much rain that the National Weather Service added new color warnings to its maps just to capture how much rain is possible, according to Capital Weather Gang, the Post's meteorology team.
Harvey is expected to dump an astounding amount of rain—as much as 35 inches in isolated areas, and 15 to 25 inches from the middle to upper Texas coast. That's why forecasters had to add a color to indicate rainfall above 20 inches was possible.
“Somebody is going to get a rainstorm to tell their grandkids about,” Bill Read, a former director of the National Hurricane Center, told the Post.
As one Twitter user described it, that puts Harvey in a unique category.
Rainfall estimates are so jaw-dropping, according to the Post, because once the hurricane hits, forecasters are anticipating it will stall along the coast for four to six days, pummeling the region with relentless rains, flooding and high winds.
Jason Godwin, a National Weather Service meteorologist in Fort Worth, tweeted on Thursday that he didn't think he had seen rainfall predictions so intense.
Peak rainfall totals are expected to be so high that some isolated areas near Corpus Christi could get as much rain in several days as the city gets on average each year—about 32 inches, according to the Weather Channel.
Rainfall isn't just an issue in Texas, either. In New Orleans, the storm could hit with as much as 20 inches of rain into early next week, according to CNN, which could compromise the city's precarious drainage system.