Tropical Depression 14 formed late Saturday morning off the coast of Mexico over the southwestern Gulf of Mexico and strengthened into Tropical Storm Milton. Forecasts from the National Hurricane Center call for rapid strengthening into a hurricane by Monday.
Although the official forecast takes Milton to a Category 2 hurricane before landfall, NHC noted upward adjustments to the intensity forecast could be required, and a Category 3 or stronger hurricane threat can’t be ruled out before Milton reaches Florida’s west coast by the middle part of next week.
With the more aggressive forecasts, the risk of life-threatening storm surge into Florida’s west coast is growing, and residents along Florida’s vulnerable Gulf Coast in low-lying areas should heed evacuation recommendations from local officials in the coming days.
Heavy rainfall and flooding will be a significant threat well ahead of Milton, beginning in earnest tomorrow on both sides of the Florida peninsula.
A sudden change in the forecast picture
The sudden shift in the forecast outlook – which less than 48 hours ago NHC had given low odds of “limited” development – came about from a new source area taking shape over the southwestern Gulf, an entirely different system than the one in the western Caribbean models were tracking earlier in the week. That earlier disturbance, as models accurately predicted, never found its footing, but the new disturbance – the remnants of a tropical depression that moved across southern Mexico from the eastern Pacific on Thursday – is what ultimately organized into Milton over the Gulf.
As we discussed in Friday’s newsletter, because now Milton is starting farther south and west than the initial disturbance forecast to its east, it has more runway beneath hostile upper-level winds to the north to organize and strengthen.
The first intensity models are bullish on future Milton’s development over the next few days. Although the official forecast brings the system to a Category 2 hurricane before landfall on Wednesday – in line with the consensus – stronger scenarios are possible, and the high-resolution hurricane models along with some of our credible global models suggest stronger scenarios are possible, especially if the system takes a more northerly track.
For now, models are in decent agreement on the track of future Milton, taking the system inland somewhere between Naples to the south and Cedar Key to the north on Florida’s Gulf Coast, with Saturday morning’s consensus zone between Fort Myers and Tarpon Springs, including places like Sarasota and Tampa.
It’s important to note that due to the upper-level wind configuration, the strongest winds and worst rain from Milton will be north of the center, but the storm surge and coastal flood threat will be highest with onshore flow to the south of where the center moves ashore along Florida’s west coast. These are important details that we’ll hopefully have a better handle on in the coming days.
Serious flood threat for parts of Florida
As we’ve discussed all week, the flood threat from prolonged heavy rainfall is perhaps the most worrisome hazard, especially for southeast Florida and areas inland.
Forecast models show the development of a Predecessor Rain Event or PRE starting as soon as tomorrow for both sides of the Florida peninsula – from Tampa southward on the west coast and from Vero Beach southward to Miami on the east coast.
This may be the first in a series of PREs, with the second heavy rain event on Monday ahead of the strengthening storm likely being the bigger flood impact day for coastal areas. These Predecessor Rain Events happen hundreds of miles ahead of tropical systems and often days before landfall, saturating soils and setting the stage for more extensive flooding.
For now both coasts should prepare for a serious flood threat through Wednesday or early Thursday. While the greatest coastal surge and wind impacts look to be on Florida’s west coast, southeast Florida, including Miami-Dade and Broward Counties, will be at greatest risk from heavy rainfall next week.
Expect widespread rain totals of over 6 inches and locally up to 10 inches or more depending on how organized future Milton gets.
Two Atlantic hurricanes staying out to sea
Kirk and Leslie are both hurricane churning over the open waters of the Atlantic. Thankfully neither storm poses any threat to land as a tropical entity, though ocean swell emanating from large and powerful Kirk will reach the U.S. Eastern Seaboard beginning tomorrow through Tuesday.
