Tropical Storm Hermine is heading for the Florida coast today, September 1, and it’s likely to make landfall as the strongest storm to hit Florida in more than a decade. The National Hurricane Center expects Hermine to make landfall on the Florida Panhandle as a category one hurricane on Thursday night, bringing with it a life-threatening storm surge, flooding rains, damaging winds, and the potential for tornadoes.

We’ve been watching this storm since it was a tiny wave coming off the coast of Africa more than two weeks ago, and it’s given meteorologists across the country a headache as they’ve tried to figure out what it would do once it got closer to land. The tropical wave quickly got its act together in the central Gulf of Mexico this week, rapidly developing into a tropical storm that continues to strengthen as it moves toward the Florida coast.

The National Hurricane Center’s forecast path for Tropical Storm Hermine over the next five days. Image credit: Dennis Mersereau

 
The 11 a.m. EDT advisory from the National Hurricane Center said that Tropical Storm Hermine has maximum sustained winds of 65 mph, and its field of tropical storm force winds (greater than 39 mph) extends 140 miles from its center. Hermine is a lopsided tropical storm—almost all of its strong winds and heavy rain are to the east of the center of circulation. Unfortunately, this will place the worst weather over most of Florida for the duration of this storm.

Forecasters expect the storm to strengthen into a minimal hurricane before coming ashore. The last time a hurricane made landfall in Florida was when Hurricane Wilma hit the southern part of the state in October 2005. However, it’s just a technicality whether Hermine is a strong tropical storm or a minimal hurricane when hits Florida. The storm will have the same impacts regardless of its official title.

After landfall, Hermine will continue to produce dangerous weather over Georgia and the Carolinas through the day on Friday and early Saturday. Hermine is expected to re-emerge in the Atlantic Ocean on Saturday and bring heavy rain and strong winds to the beaches—not an ideal scenario, given that Labor Day weekend is a popular time for folks to head to the beach.

FLOODING RAINS

Forecast precipitation totals (in inches) between September 1 and September 6, 2016. Image credit: WPC

 

The greatest threat from Tropical Storm Hermine will be flash flooding due to heavy rain. The Weather Prediction Center expects that Hermine will drop a widespread area of 6 to 12 inches of rain along its path, which is expected to stretch across the southeast states while grazing coastal areas of the Mid-Atlantic and Northeast. Persistent heavy rains will lead to life-threatening flash flooding in spots. Stay alert for flood watches and warnings in your area, and please don’t drive through a flooded roadway—you can’t tell how deep the water is until it’s too late, and it only takes a foot of moving water to sweep away vehicles.

STORM SURGE

One of the quietest but most dangerous aspects of Hermine will be the storm surge, or the seawater pushed inland by the storm’s strong winds. The storm surge is often the deadliest hazard in a landfalling tropical cyclone. A storm surge comes up quickly, sometimes faster than you can react. Not only is the water itself dangerous, but the debris and chemicals floating around in the water can be harmful as well.

Meteorologists expect storm surge flooding across a large swath of the Florida Gulf Coast, with the worst flooding along and to the east of where Hermine makes landfall. Coastal cities like Destin and Tampa could see storm surge flooding of 1 to 3 feet above ground level during the worst of the storm, and areas up in the Big Bend—like Apalachicola and areas south of Tallahassee—could see a storm surge of 4 to 8 feet above ground level.

WIND

Hermine’s strong winds will likely cause tree, power line, and building damage along its path. Falling trees and blowing debris are potentially deadly if you’re not in a safe place during the storm. Heavy rain that saturates the ground will make it easier for the storm to blow over trees and power poles, likely leading to widespread power outages in areas that experience the worst conditions. Make sure you’re prepared for a power outage by checking to make sure you have enough nonperishable food, water, medicine, and gas in your car to make it at least a couple of days without electricity. Don’t forget some cash if you can swing it—your debit or credit card is all but useless if there’s no power.

TORNADOES

Every landfalling tropical cyclone comes with the threat of tornadoes. Some of the worst summertime tornado outbreaks in the United States were the result of tropical cyclones coming ashore. The strong wind shear in the atmosphere can lead to small, fast tornadoes that sometimes happen so quickly that weather radar can’t detect them until it’s too late (or never detects them at all). Even the smallest and weakest tornado is dangerous if you’re in its path. The greatest tornado threat generally lies to the right of the storm’s forward motion—in this case, across the Florida peninsula and through eastern parts of Georgia, South Carolina, and North Carolina.