We knew 2020′s tropical season had the potential to be busy, but it really came to life this past week. Now, two tropical systems - Tropical Storm Laura and Hurricane Marco - are forecast to reach the Gulf by Tuesday. While there remains much uncertainty when it comes to strength and path, just how rare is this occurrence?
UPDATED FORECASTS HERE: The latest forecast for Tropical Storms Marco and Laura
Has there ever been two hurricanes in the Gulf at the same time?
No. The closest seems to be on Sept 4, 1933, when a major hurricane was over south Florida and another major hurricane was over the western Gulf of Mexico.
When is the last time two tropical cyclones were in the Gulf of Mexico simultaneously?
September 5-6, 2002
- Tropical Storm Fay (in the northwest Gulf of Mexico)
- Tropical Depression Edouard (weakened after crossing Florida from east to west)
- Overlap was about 18 hours
June 17-18, 1959
- Tropical Storm Beulah (made landfall well south of the US-Mexican border)
- Hurricane 3 (was a tropical storm in the Gulf, before crossing the Florida Peninsula and intensifying over the Atlantic)
- Overlap was about 8 hours
When is the last time that two tropical cyclones in the Gulf of Mexico simultaneously directly affected the United States mainland?
September 4, 1933
- Hurricane 8 (landfall in deep South Texas as a major hurricane)
- Hurricane 11 (Hurricane 11 weakened to a tropical storm after crossing the Florida Peninsula and briefly entered the Gulf of Mexico near Cedar Key, Florida)
- Overlap was very brief, about 4 hours
There was one more recent case in 1974 where a tropical depression and subtropical storm occurred at the same time: June 24-25, 1974
- Tropical Depression 1 (formed in Bay of Campeche)
- Subtropical Storm 1 (rapidly moved west-to-east toward, and eventually across, the Florida Peninsula)
- Overlap was about 12 hours (18Z 24 Jun 1974 to 06Z 25 Jun 1974)
Were there any other near misses in the recent past?
Yes, two in the satellite era. In 2004, Tropical Storm Bonnie made landfall in the Florida Panhandle about 16 hours before Hurricane Charley emerged into the Gulf after passing over Cuba. In 1971, Fern made landfall as a tropical storm in Texas about 24 hours before Edith emerged into the Bay of Campeche as a tropical storm after crossing the Yucatan Peninsula.
Has there ever been two hurricanes that make landfall in the mainland U.S. within days of each other?
Yes, although rare, there have been 10 instances of the United States having hurricane landfalls within 5 days of each other. (1869, 1879, 1893, 1903, 1933, 1940, 1949, 1960, 2004, 2005)
In 1933, Hurricanes #8 and #11 (storms were not named then) made landfall within one day of each other, striking Texas and Florida.
Is there a chance that these two systems could “combine” to form a larger hurricane?
In a sense, yes. Read more about the Fujiwhara effect here.
BUT... The National Hurricane Center states: There’s nothing “usual” about this type of interaction in the Atlantic basin. More often than not, the storms deflect around each other, or the larger storm destroys the other one. It is quite rare to have a perfect combination to form “a larger hurricane”
How might these two systems interact if they don’t combine?
The eventual tracks of each system could be influenced by the other as they both enter the Gulf, as the circulation associated with the larger and stronger system would tend to modify the track of the other system in terms of its direction and/or forward speed. The intensity of one system may also be influenced by the other, especially if strong upper-level winds associated with the outflow of one system cause increased vertical wind shear over the other system. The details of these interactions are quite sensitive to the exact track, intensity, and size of the individual systems, and may not be clear for some time.
You can follow along with Your Weather Authority as we continue to track the tropics by downloading the KSAT Weather Authority app for Apple or Android and allow notifications for updates, including livestreams from KSAT meteorologists.
Our KSAT Hurricane Tracker app also allows you to monitor the tropics from your phone during the Atlantic Hurricane Season, which runs until November 30.