National Oceanic and Atmospheric Administration
As is common in July, the tropical Atlantic went into a lull after Hurricane Beryl battered Texas and the short-lived Tropical Storm Chris moved into Mexico, but now that we’re well into August and African dust has receded from the atmosphere, the ocean is waking up.
Tropical Storm Debby The storm formed over the weekend and forecasters at the National Hurricane Center say it could reach Category 1 strength before making landfall along Florida’s western coast on Monday.
As a hurricane, this is not the most threatening storm that Florida has seen in recent years. Sure, nobody likes hurricanes or the storm surge they bring. But Debby will likely batter less populated areas of Florida and dump most of its wrath on nature preserves and wildlife refuges. It’s not going to be fun, but as a hurricane, it will be quite manageable from a wind and storm surge standpoint.
Major flood storms expected
But Debby poses a much greater threat, threatening to cause severe flooding in the southeastern US over the next week, with historic flooding possible in parts of Florida, Georgia and South Carolina.
As of Sunday morning, Debby was moving north-northwest at a respectable 13 mph, a common path for hurricanes as they skirt the edge of high pressure, then once they gain enough latitude, as Debby is currently doing, they will turn poleward and eventually move northeastward.
Debbie is planning on strolling next week.
National Hurricane Center
And Debby is expected to remain just that way through about Monday, until a high pressure system forms over the central Atlantic that may strengthen enough to block Debby’s northeastward escape route, trapping the storm near the Georgia and Carolina coasts for a few days.
There’s still a lot of uncertainty about where Debby will go after it hits Florida. It will probably cross Georgia on Tuesday before its center re-emerges in the Atlantic Ocean. Either way, the center will likely be near the coast or offshore. From there, Debby will move into very warm oceans, around 83 to 85 degrees Fahrenheit.
In such a pattern, as the storm is nearly stationary, the rainband is continually replenished by moisture drawn in from the ocean. This causes heavy tropical rainfall and “training,” where offshore moisture causes the rainband to become more or less stationary over a given area.
Because this pattern is still several days away from taking hold and Debby’s path is still uncertain, it’s impossible to say exactly where the heaviest rain will fall, but the Weather Prediction Center, the division of the National Weather Service responsible for forecasting rainfall, is predicting some pretty astonishing amounts of rain between now and Friday.
Weather Bell
The Weather Prediction Center expects snowfall amounts of 20 to 25 inches from Savannah, Georgia, north to Hilton Head Island and Charleston, South Carolina, with some areas potentially even more. What’s more, the height of these precipitation amounts could extend dozens of miles inland.
The African Wave Train Gets Moving
Due to the uncertainty around Debby’s movement, parts of Florida and North Carolina may also see very heavy rainfall over the next few days.
But that’s not all. As August progresses, tropical waves are starting to eruption off the west coast of Africa. One of them is currently approaching the Windward Islands and should move into the Caribbean next week, where it could develop into a tropical storm or worse. This could be the start of a period of intense activity in the tropical Atlantic that characterizes August, September, and early October.
All of this is in line with forecasters predicting an unusually hot Atlantic hurricane season due to an unusually warm Atlantic Ocean (ocean temperatures are the warmest in modern history due to climate change) and a looming La Niña event in the Pacific, which is creating favorable conditions for hurricane formation in the Atlantic basin, including the Caribbean and Gulf of Mexico.
