Zeta is weakening rapidly, but still spreading damaging winds in a swath across the South, including metro Atlanta. In addition, heavy rain today and tomorrow will bring a threat of flooding from the South to the Northeast. The storm is being propelled by an unusually strong upper-level system coming out of Texas. The upper-level system will slowly absorb Zeta and create a new formidable storm off the Northeast coast tomorrow.
Hurricane Zeta made landfall late yesterday afternoon south of New Orleans with top winds estimated at 110 mph. Gusts over 130 mph were measured in southern Louisiana. Zeta’s winds ended up being stronger and the storm surge higher than the forecasts anticipated just yesterday morning.
The giant upper-level storm to the west of Zeta was about 6 hours late in getting to Louisiana – later than forecast, that is – so the atmospheric environment over the storm as Zeta approached the coast did not deteriorate as soon as expected. As the center was making landfall, the hostile upper winds finally arrived, and the bad weather was pushed to the front side of the storm.
That delay meant that Zeta remained in a very supportive atmospheric environment up until it reached Louisiana.
The current estimate is that Hurricane Zeta came in just below Category 3 strength. The lesson here, which we often reiterate, is that we have to prepare for at least a category higher storm than is forecast. In this case, Zeta was almost two categories stronger.
Unfortunately, the mechanisms that make a hurricane intensify or weaken 20 or 30 mph are sometimes so subtle that they cannot be detected or forecast. It’s unclear if we will ever be able to measure the atmosphere at a resolution that will always solve the riddle of rapidly intensifying or weakening storms.
The last 4 storms to make landfall in the U.S. have all rapidly intensified near landfall – a lesson for us to carry forward.
As the eye tracked directly over metro New Orleans, the maximum storm surge pushed over the coast in Mississippi and southeastern Louisiana. There was major flooding along that coastline, but we’ll have to await an assessment to find out the lasting effects of the storm south and east of New Orleans.
As the new combo storm forms off the Northeast coast on Friday, it will push a cold front through the South and finally into South Florida over the weekend. The current expectation is that it will be weak, but some drier air will filter in beginning early Saturday.
Quickly however, another front will follow. And this one will be strong. Dramatically drier and cooler air is expected Monday into Tuesday – a real change of the season. Election Day should be sunny, breezy, and coolish across Florida.
Far to the south, the National Hurricane Center is noting the possibility of tropical development early next week in the extreme southern Caribbean Sea. As we’ve discussed, the long-range computer models have been forecasting the atmospheric pattern to be conducive for development.
A Tropical Disturbance approaching the southeastern Caribbean islands will arrive in the zone conducive for development over the weekend. If the system organizes and develops winds over 40 mph, it will be named Tropical Storm Eta (pronounce AY-tuh).
Whatever develops would likely continue west into Central America, and it could be a formidable storm there, especially in the mountainous areas.
For the foreseeable future, a fall weather pattern will keep any tropical system far to the south of Florida and the U.S. coast.