Hurricane Milton barrels toward a ferocious nighttime landfall on Florida’s west coast » Yale Climate Connections

Track forecast for Milton

Ever since Milton became a tropical depression on Saturday, October 5, its arcing track toward a Florida west-coast landfall has been well predicted by the National Hurricane Center, allowing ample time for response. After Milton swung near the north coast of the Yucatan Peninsula late Monday and Tuesday, the hurricane angled northeastward and is now on a steady track toward the Florida coast. Milton’s track across much of the Gulf has been closer to the south edge than the north edge of the regularly updated “cones of uncertainty.” The official NHC forecast has remained close to the track-model consensus, with the center of each cone close to Tampa Bay but nudging slightly southward over time.

Milton has been steered largely by a weak upper-level low to the northwest and an upper-level high centered near the Bahamas. As Milton nears the coast of Florida, it will feel the increasing tug of an upper-level trough near the U.S. East Coast, which should keep the hurricane on its general northeastward track. Milton’s core is expected to reach the Florida coast, most likely between the Tampa Bay area and Venice, between around 6 p.m. and midnight Wednesday night and quickly cross the state, emerging into the Atlantic on Thursday morning – likely still at hurricane strength – while angling slightly rightward (eastward). A continued east-northeast movement is expected as Milton transitions into a tropical storm on Thursday and then becomes gradually weakening post-tropical cyclone, likely passing south of Bermuda over the weekend.

Small, impossible-to-predict wobbles along the track can be expected, even in the last few hours before landfall, and these could make a big difference in where Milton’s eyewall winds and storm surge are the worst (see surge discussion below). As the National Hurricane Center noted in its 11 a.m. EDT advisory on Wednesday: “We would like to emphasize that Milton’s exact landfall location is not possible to predict even at this time, particularly if the hurricane wobbles during the day and into this evening. Even at 12-24 hours, NHC’s track forecasts can be off by an average of 20-30 nm [23-35 miles].” A variety of serious hazards will affect large parts of Florida regardless of track wobbles, and residents should prepare for the worst, knowing that the stakes of underestimating Milton could be enormous.

Intensity forecast for Milton

Milton reached Category 5 strength for a second time on Wednesday afternoon, making it one of just three hurricanes on record to do so in the Gulf of Mexico along with Camille (1969) and Allen (1980). Both Camille and Allen developed in August rather than October, whereas Milton’s exceptional late-season strength has been fueled by Gulf waters at record warmth for so late in the season. Estimates from Climate Central found that the odds of such warmth were boosted 400- to 800-fold by human-caused climate change.

Read: Climate change made Hurricane Helene and other 2024 disasters more damaging, scientists find

Milton will remain an extremely dangerous storm on its final approach to Florida even as its top sustained winds decrease gradually. Wind shear associated with the East Coast upper-level trough will ramp up on Thursday, and dry air will be wrapping around Milton’s south side. These processes will continue to make the hurricane more asymmetric, with the heaviest rains concentrated north of Milton’s track and scattered thunderstorms rather than more widespread rain south of Milton’s track.

Milton is predicted to make landfall as a Category 3 storm, but it would not be surprising to see it reach the coast at high-end Cat 2 or low-end Cat 4 strength, depending on how the hurricane evolves in its final hours before landfall. This will have little impact on the storm surge strength, though.

Milton is predicted to remain at hurricane strength while crossing Florida, most likely exiting the coast somewhere between Melbourne and Daytona Beach. A narrow corridor of damaging west winds may develop just south of Milton’s center as it moves across the state. Extremely powerful wind gusts can also be expected within the torrential rains north of the center. A much broader area will experience tropical-storm-force winds (sustained at 39 mph or higher), which can be strong enough to bring down trees and power lines, and residents across much of the central and northern Florida Peninsula should be prepared for massive, prolonged power outages.

Latest track scenarios with the consensus 3-second peak gust forecast pic.twitter.com/MYm6H8KcaX

— Moody’s RMS HWind (@hwind) October 9, 2024

Milton’s peak storm surge likely near Venice, Florida

Milton’s tremendous Cat 4 and Cat 5 winds over the past three days have put a large amount of ocean water on the move. If Milton weakens to Cat 3 strength by landfall, as currently predicted by the official National Hurricane Center forecast, this process will spread Milton’s strongest winds over a wider area of ocean, increasing the volume of water put in motion. When Milton crosses over into the shallow waters of the continental shelf, 90 miles (145 km) offshore of Florida, this swirling water will form a large dome that will push onto the shore, creating a massive and destructive storm surge that will be more characteristic of a Cat 4 hurricane than a Cat 3 hurricane. A sobering fact: three of the most destructive Atlantic hurricanes on record were former Cat 4 or Cat 5 storms that were weakening in the 12 hours leading up to landfall. These include the costliest weather disaster in world history (Hurricane Katrina of 2005, with $191 billion in damage; Cat 5 peak, Cat 3 at landfall), Hurricane Rita of 2005 ($28 billion; Cat 5 peak, Cat 3 at landfall), and Hurricane Opal of 1995 ($10 billion; Cat 4 peak, Cat 3 at landfall).

On Monday, Milton was a small hurricane with tropical-storm-force winds that extended out 80 miles (130 km) from the center. But after undergoing an eyewall replacement cycle Tuesday and broadening of the wind field from interaction with a low-pressure system to its northeast over the past day, Milton has expanded in size. At 11 a.m. EDT Wednesday, tropical storm-force winds extended out up to 240 miles (385 km) from the center. Further expansion of the wind field, to 275 miles (440 km) from the center, is predicted before landfall, which would further increase the Milton’s size and surge potential.

This large wind field is likely to bring the highest storm surge on record along an 80-mile (130-km) swath of Florida’s west coast near and to the right of where the eye makes landfall. A storm surge of about one foot (0.3 m) was occurring along Florida’s west coast early Wednesday afternoon, but no coastal flooding was occurring, since the tide was going out. Low tide at Venice, where the highest storm surge is expected, is near 1 p.m. EDT. Water levels will ramp up this evening as Milton approaches landfall and the tide comes in. The latest National Hurricane Center forecast calls for Milton to make landfall near 9 p.m. EDT, which would be mid-tide, since high tide is near 4 a.m. The difference between high tide and low tide is about two feet, so Milton’s storm surge is likely to be about one foot lower than the 10-15-foot-range given in the NHC surge forecasts (which assume that the peak surge will arrive at high tide).

A devastating storm surge in Tampa Bay still cannot be ruled out

The National Hurricane Center forecast at 11 a.m. EDT Wednesday called for a landfall near Sarasota, about 10 miles south of the entrance to Tampa Bay. If this landfall location were to occur, Tampa Bay would experience hurricane-force offshore winds, which would blow water out of the bay and prevent a massive 10-15-foot storm surge. A lesser surge of up to 3 feet (0.9 m) would be likely in the bay as the storm moved inland to the northeast, bringing onshore flow along the backside of Milton. The official National Hurricane Center forecast has held to this idea for over a day now, so there is increasing confidence that Tampa Bay will avoid a worst-case storm surge scenario.

However, it is still possible that Milton could wobble to the north and make landfall 20 miles farther to the north, over St. Petersburg. This would allow the powerful right-front winds of the hurricane to push water directly into Tampa Bay, bringing a massive 10-15-foot storm surge. A wobble of a mere 20 miles (32 km) in track would make all the difference, with tens of billions in storm surge damage occurring with a more northerly track over St. Petersburg, and perhaps less than a billion with a more southerly one over Sarasota. Since the accuracy of a 12-hour National Hurricane Center forecast is on the order of 20-25 miles (32-40 km), we won’t know until late this afternoon whether or not Tampa Bay will see a disastrous storm surge. With tons of debris lying at the side of streets two weeks after Hurricane Helene brought a record five to eight feet of storm surge to the bay, the region desperately needs Hurricane Milton to pull its punch.

A record storm surge in northeastern Florida expected

When Milton emerges off the Florida east coast on Thursday morning, the hurricane’s wind field will be even larger, driving a storm surge of three to five feet to the coast of northeastern Florida and Georgia. Water levels at Jacksonville, Florida, are predicted to peak at about four feet above the high tide mark near 3 p.m. EDT Thursday, which would be the highest water level ever observed (records go back to 1928). Widespread evacuation orders have been given in the region.