(Vox) – Hurricane Harvey: It’s hard to fathom the amount of rain Hurricane Harvey dumped on Texas and Louisiana. Some weather stations in the region recorded more than 50 inches (over 4 feet!). It’s a once-in-1,000-years flood and the consequences have been catastrophic: at least 46 are dead, around 30,000-40,000 homes have been destroyed, and 35,000 people relocated to emergency shelters. The recovery is expected to cost well more than $150 billion, and it will take years to complete.
It’s all because over six days, 27 trillion gallons of water fell over Texas and Louisiana, as Ryan Maue, a meteorologist with WeatherBell, told CNN. (The calculation is simple, he says on Twitter: It is depth of rain multiplied by the number of square miles covered.) That’s one million gallons of water for nearly every person who lives in Texas. For reference, here’s what one million gallons of water looks like hovering above an average-sized person.
Twenty-seven trillion gallons is much harder to fathom. To help, we wondered what 27 trillion gallons would look like in one giant raindrop. Its size is reminiscent of a mushroom cloud.
Harvey’s total rainfall dwarfs the amount of rain dumped over Louisiana and Mississippi during Hurricane Katrina in 2005. That storm produced 6.56 trillion gallons over those states, which goes to show the vast difference between Katrina and Harvey. Katrina brought destruction via storm surge and the crumbling of New Orleans levees. Harvey stalled over the coast after making landfall.
An Irresponsible, Irrepairable Irma
Hurricane Irma is an absolute monster of a storm. Its powerful winds have kept it a Category 5 (the highest on the Saffir-Simpson wind scale) for more than two days, which makes it one of the most powerful and longest lasting Category 5 storms on record, and with two and a half days until a possible Florida landfall, it doesn’t seem to be losing steam.
As of Thursday (September 7, 2017) afternoon, Irma was blowing sustained 175 mph winds. “That’s similar to a tornado, except this tornado is 80 miles wide,” says Jeff Weber, a meteorologist with the National Center for Atmospheric Research.
Much of South Florida is now under a hurricane and storm-surge watch. That means the National Hurricane Center believes dangerous winds, rains, and coastal flooding could arrive by Sunday. The greatest danger in a hurricane is usually flooding from storm surge. The hurricane center predicts 5 to 10 feet of surge will be from the Jupiter Inlet (just north of West Palm Beach) on the Atlantic Ocean, through the Florida Keys in the Gulf – an area that spans hundreds of miles. Impacts in Georgia and Carolina are also a possibility.
Irma is expected to maintain a Category 5 status for the remainder of its path toward Florida, through Turks and Caicos and the Bahamas.
We’re witnessing a truly extreme event. But as Weber and Phil Klotzbach, an atmospheric scientist at Colorado State University, explain, this is the exact time of year you’d expect the most powerful storms to form. It’s also not that surprising to see multiple tropical cyclones forming at once, as we’re seeing with Hurricanes Jose and Katia, which could also make landfall this weekend.
But for a monster like Irma, all the conditions – that are actually quite common for this time of year – have lined up. “You need a perfect recipe to get a storm like Irma,” Klotzbach says.
And we have it.