Tropical Storm Gordon is bearing down on the Gulf Coast today expecting to make landfall around the Gulfport, Mississippi area sometime this evening. Anyone that works in transportation knows just how destructive and disruptive tropical systems can be. The impact of hurricanes Harvey and Irma can still be felt in the freight market today. Gordon does not appear to be on the same level as either of those systems, but tropical systems, large or small, are nothing to take lightly.
Although it may not seem like it, the 2018 Atlantic hurricane season has not been too dissimilar from 2017 to this point. In 2017 there were seven named systems by mid-August, with two becoming hurricanes. In 2018 the numbers are the same but instead of mid-August it is early September before hitting the “G”-named storm.
Tropical systems generally get names when they produce sustained winds of approximately 38 mph, but there are exceptions when the governing organizations feel it is a significant enough event to warrant a name. There is a list of 21 names decided on by the World Meteorological Organization in alphabetical order, and the “G” storm is the seventh on the list each year. Last year, there was forgettable Gert that formed in the open Atlantic and never came close to any land before fizzling.
One of the main differences in 2017 and 2018 is that the tropical Atlantic has had few storms threaten the U.S. mainland this season as opposed to last year. Sub-tropical storm Alberto, which formed in the Gulf in late May prior to the official start of the Atlantic hurricane season on June 1, was a non-event dropping some heavy rain on the interior U.S. but causing little to no lasting impact.
Gordon appears to be on track to remain a strong tropical storm with some potential to become a minimal hurricane with maximum sustained winds of 74 mph by the time it lands somewhere along the Mississippi and Alabama coast. It is forecast to drop 5-7 inches of rain as far inland as Oklahoma, with a high probability of localized flooding all the way up to the already-soaked Midwest.
According to a Weather Channel interview with Ken Graham, the director of the National Hurricane Center, “We should be thinking about rain and storm surge as the main focus.” Flooding is the main cause of loss of life and damage in a tropical system. The storm is expected to hit during a period of lower tide, which should decrease the extent of the damage, but it is hitting an area that is more susceptible to storm surge damage as there are many rivers draining into the ocean at the projected point of landfall.
Louisiana is showing its concern by canceling school for the day, taking no chances with the storm as New Orleans sits between two bodies of water in a bowl-like valley, with Lake Pontchartrain to the north and the Mississippi River to the south. Levies and pumping systems protect the city from flooding but have limitations to the amount of water they can handle. Gordon is not expected to exceed those boundaries.
The main concern for transportation will be any infrastructural damage that requires emergency relief and any capacity that is taken due to increased demand. In the near term, the Mobile port area is not a large center of outbound freight, but many trucks drive across the I-10 corridor and will more than likely experience significant delays later today if not rerouted.
The main significance of Gordon is not necessarily Gordon, but what it means for the rest of the year. The tropical Atlantic has been subdued in the main development region (MDR), the tropical low latitude region north of the equator where many storms develop before threatening the Caribbean and U.S. Only two storms have developed in the area this year. Seven storms developed there in 2017, including major Hurricanes Maria and Irma. The idea is that the storms have longer to develop, increasing the odds of a major hurricane hitting the U.S.
So far, the ocean temperatures have been cooler than average, and a layer of Saharan dust has kept the atmosphere drier than normal over the MDR. Gordon may not have formed there, but its origins as a tropical wave survived the non-conducive environment, the first to do so all year.