Rising winds, heavy rains, and a significant storm surge are already affecting the coast of southeast Louisiana, where Hurricane Zeta is expected to come ashore late Wednesday afternoon as a category 1 or 2 hurricane. Zeta, likely to be a multi-billion-dollar storm for the U.S. Gulf Coast, will be the eleventh named storm to make landfall in the U.S. so far in 2020, beating the record of nine U.S. landfalls set in 1916. Update: Zeta made landfall at 4 p.m. CDT Wednesday in southeastern Louisiana near Cocodrie as a high-end category 2 hurricane with 110 mph winds.
Wind and storm surge damage are the main threats posed by Zeta. New Orleans’ levee system is expected to be able to handle the expected peak storm surge of six to nine feet without incident, but surge damages will be heavy in southeastern Louisiana beyond the New Orleans levee system.
Zeta’s curving path to the northeast at landfall will bring the Mississippi and Alabama coasts a significant storm surge. The western Florida Panhandle is also predicted to see a damaging storm surge of two to four feet. High tide in New Orleans and along the Mississippi coast is near 6 p.m. CDT Wednesday, but with the difference between the day’s low tide and high tide less than four inches, the timing of Zeta’s landfall is less critical with respect to peak storm tide levels.
Zeta’s curving track at landfall will bring the strong winds of the right front eyewall to a wide swath of the coast, from southeast Louisiana to Mississippi. Given the storm’s very fast forward speed of more than 25 mph at landfall, the winds on the right (east) side of Zeta’s center will be 20 to 30 mph stronger than those on the left (west) side, according to the Wednesday morning runs of the high-resolution hurricane models.
Fortunately, Zeta’s rapid forward speed at landfall will limit rainfall amounts. The current National Hurricane Center forecast calls for two to four inches of rain, with isolated amounts of up to six inches – an unusually low amount for a landfalling hurricane. With one of New Orleans’ key pumps to drain the city of excessive rainwater not operating, though, Zeta may still cause damaging rainwater flooding in the city.
Zeta rapidly intensifying Wednesday
Hurricane hunter aircraft from NOAA and the Air Force reported a steady strengthening of Zeta on Tuesday night and Wednesday, with the central pressure falling from 990 mb at 7 p.m. CDT Tuesday to 970 mb at 4 p.m. CDT Wednesday, and surface winds rising from 65 mph to 110 mph. The NOAA Hurricane Hunters measured a significant wave height of up to 24 feet near the center of Zeta.
Update: In the 24 hours ending at 4 p.m. CDT October 28, Zeta’s 45-mph increase in winds exceeded the National Hurricane Center’s definition of rapid intensification of at least a 35-mph increase in winds in 24 hours. Zeta is the eighth 2020 Atlantic named storm to rapidly intensify, and the fourth consecutive one to do so:
Hurricane Hanna, July 24–25, 35 mph in 24 hours;
Hurricane Laura, August 26–27, 65 mph in 24 hours;
Hurricane Sally, September 14–15, 40 mph in 24 hours;
Hurricane Teddy, September 17–18, 45 mph in 24 hours;
Tropical Storm Gamma, October 2-3, 35 mph in 24 hours;
Hurricane Delta, October 5–6, 80 mph in 24 hours;
Hurricane Epsilon, October 20–21, 50 mph in 24 hours; and
Hurricane Zeta, October 27-28, 45 mph in 24 hours.
Hurricanes Isaias, Marco, Nana, and Paulette of 2020 did not rapidly intensify. According to statistics compiled by Tomer Berg, the highest number of rapidly intensifying Atlantic storms since 1979 occurred in 1995, with 10.
Track and intensity forecasts for Zeta
There isn’t much mystery about where Zeta will make landfall, with southeastern Louisiana squarely in the crosshairs of the storm, according to the tightly clustered computer model forecasts. The eye of Zeta will make landfall between 4 p.m. and 7 p.m. CDT in Louisiana, pass over a portion of the New Orleans metropolitan area, and then move into Mississippi about three hours after its initial Louisiana landfall.
It appears that the hoped-for wind shear to weaken Zeta will be late to arrive, and the hurricane will have at least marginal conditions for intensification for most of the remaining hours before landfall. Ocean temperatures beneath Zeta will fall from 27 degrees Celsius (81°F) to 26 degrees Celsius (79°F), and wind shear will increase from about 10 knots to 20 knots – still in the moderate range. Zeta is well-organized enough to be able to resist this expected increase in wind shear and cooling of ocean temperatures. The top intensity models generally predicted with their Wednesday morning runs that Zeta would be a category 1 or 2 hurricane at the time of landfall in Louisiana, and a reasonable uncertainty range for Zeta’s landfall intensity is between 75 and 110 mph winds – category 1 or 2 hurricane strength.
The live storm surge tracker at Trabus Technologies showed Zeta was generating a storm surge in excess of two feet along the Louisiana coast Wednesday afternoon. As of 4 p.m. CDT Wednesday, top storm surge levels observed were:
Port Fourchon, LA: 3.1 feet;
Freshwater Canal Locks, LA: 2.8 feet; and
Southwest Pass, LA: 2.5 feet.
Zeta likely to be one of strongest landfalling U.S. hurricanes so late in the year
Going back to 1851, only five hurricanes have made a mainland U.S. landfall on October 28 or later; Zeta is likely to be the sixth (see Tweet by Steve Bowen of Aon). The five hurricanes were:
Kate, November 21, 1985, category 2, 100 mph winds;
Juan, October 29, 1985, category 1, 85 mph winds;
Unnamed, November 4, 1935, category 2, 100 mph winds;
Unnamed, October 31, 1899, category 2, 110 mph winds; and
Unnamed, November 2, 1861, category 1, 80 mph winds.
Dr. Phil Klotzbach of Colorado State University says Zeta is the strongest hurricane ever recorded so far to the west in the Gulf of Mexico this late in the year. If Zeta makes landfall as a hurricane, it will be the sixth continental U.S. landfalling hurricane this year, tying 2020 with 1886 and 1985 for most continental U.S. landfalling hurricanes in a single Atlantic season on record.
Zeta will also be the fifth named storm to make landfall in Louisiana this year, along with Tropical Storm Cristobal, Tropical Storm Marco, Hurricane Laura, and Hurricane Delta. The previous record for most landfalls in a single season in Louisiana was four in 2002, when Tropical Storm Bertha, Tropical Storm Hanna, Tropical Storm Isidore, and Hurricane Lili all made landfall.
What if the name Zeta needs to be retired?
According to the World Meteorological Organization, if the name Zeta needs to be retired from the list of hurricane names as a result of its impact on Mexico and the U.S., it would be retired as “Zeta 2020” and Zeta would continue to be used when the Greek alphabet is needed again.
Delta, which made landfall in western Louisiana on October 9 as a category 2 storm with 100 mph winds, is already a candidate to have its name retired in this fashion. Risk modeler RMS is estimating that Delta did up to $5 billion in insured damage to the U.S. and Mexico, and additional billions in uninsured damage may yet add to that hefty price tag.
Historically, the names of every hurricane doing at least $3 billion in damage have been retired.
Mexico’s Yucatan Peninsula cleans up after Zeta becomes third ‘Greek’ storm of October
Hurricane Zeta made landfall near Tulum, Mexico at 11 p.m. CDT Monday night, October 26, as a category 1 storm with 80 mph winds and a 978 mb central pressure.
Near the time of landfall, a Weatherflow station just south of Playa del Carmen reported sustained winds of 74 mph with a gust to 87 mph. Another Weatherflow station in Cancun reported sustained winds of 60 mph with gusts up to 79 mph. A storm surge of over one meter (3.28 feet) was observed at Puerto Morelos, and rainfall amounts of up to seven inches occurred about 50 miles inland from Zeta’s landfall location.
Zeta did considerable damage to trees, power poles, and billboards in Mexico, but no major damages or deaths or injuries were reported, said the governor of the Quintana Roo state. Tree damage was higher than is usual for a category 1 hurricane, as many of the trees had already been weakened by the landfalls of category 2 Hurricane Delta (110 mph winds) on October 7 and Tropical Storm Gamma (70 mph winds) on October 3. Zeta knocked out power to 253,000 customers in Mexico, but service had been restored to nearly 80% of them by Tuesday night.
Posted on October 28, 2020(1:20pm EDT).