Tropical Storm Isaias Is Forecast to Become a Hurricane Thursday, With Gulf Coast Watches Up

Photo: https://ourgulfshoresvacation.com, CC BY-SA 4.0, via Wikimedia Commons — A Gulf Coast beach at Gulf Shores, Alabama, on a calm day in 2019 (file photo; the Hurricane Watch for Isaias covers part of this coast).

As of about 2:05 p.m. EDT Wednesday, Oct. 7, 2026 (Intermediate Advisory 4A, 1:00 p.m. CDT), the National Hurricane Center says Tropical Storm Isaias is strengthening in the Gulf, about 255 miles west-northwest of Progreso, Mexico, and is forecast to become a hurricane on Thursday and approach the U.S. northern Gulf Coast on Friday, with hurricane, tropical storm and storm surge watches already in effect from Louisiana to Florida.

The National Hurricane Center has updated its forecast several times since Tuesday evening, and the next complete advisory is scheduled for 4 p.m. CDT (5 p.m. EDT).

Where Isaias is and what the National Hurricane Center expects

In Intermediate Advisory 4A, issued at 1:00 p.m. CDT (2:00 p.m. EDT), the center of Tropical Storm Isaias was near latitude 22.6 North, longitude 93.4 West, as located by NOAA Hurricane Hunters. That is about 255 miles west-northwest of Progreso, Mexico, and about 520 miles south-southwest of the mouth of the Mississippi River.

Maximum sustained winds were near 50 mph, with higher gusts. The storm was moving east-northeast at 8 mph. The estimated minimum central pressure was 997 mb (29.44 inches), based on NOAA dropsonde data. Tropical-storm-force winds extend outward up to 45 miles from the center.

The headline of the advisory reads: “NOAA Hurricane Hunters find Isaias gathering strength.” The forecast in Advisory 4A says “Some strengthening is forecast during the next 48 hours, and Isaias is forecast to become a hurricane on Thursday.” The first of the center’s key messages in the Advisory 4 discussion goes further: “Isaias is expected to strengthen into a strong hurricane before approaching the northern Gulf Coast on Friday.”

The Advisory 4 forecast table (10:00 a.m. CDT) puts the storm’s maximum sustained winds at 75 mph (65 knots) in 24 hours and 110 mph (95 knots) in 48 hours, up from 45 mph at the time of that advisory.

On the forecast track, the advisory says a continued east-northeast motion is expected today, then a turn toward the northeast and north on Thursday and Friday. Isaias is expected to pass north of the Yucatan Peninsula on Thursday and approach the U.S. northern Gulf Coast on Friday. The advisory does not name a landfall location or time, and neither does this article.

Advisory 4A also says: “Gusty winds are possible in portions of the Yucatan Peninsula on Thursday.” The Advisory 4 discussion says Isaias “could bring gusty winds and areas of heavy rain to the western portion of the Yucatan Peninsula over the next day or so.”

Watches in effect and what each one means

Advisory 4 (10:00 a.m. CDT, 11:00 a.m. EDT Wednesday) was the first to issue coastal watches. Advisory 4A made no changes. As of Advisory 4A, these are in effect:

A Storm Surge Watch, from the mouth of the Mississippi River to Yankeetown, Florida.
A Hurricane Watch, from Bay St. Louis, Mississippi, to Indian Pass, Florida.
A Tropical Storm Watch, from the Jefferson/Plaquemines Parish line, Louisiana, to west of Bay St. Louis, and from east of Indian Pass to the Aucilla River, Florida.

The National Hurricane Center defines them this way. “A Storm Surge Watch means there is a possibility of life-threatening inundation, from rising water moving inland from the coastline, in the indicated locations during the next 48 hours.” A Hurricane Watch “means that hurricane conditions are possible within the watch area.” The advisory adds that such a watch “is typically issued 48 hours before the anticipated first occurrence of tropical-storm-force winds, conditions that make outside preparations difficult or dangerous.” A Tropical Storm Watch “means that tropical storm conditions are possible within the watch area, generally within 48 hours.”

Advisory 4A lists only watches; no warnings are in effect. It says: “Additional watches and warnings could be required for a portion of the U.S. northern Gulf coast later today.” On timing, it says hurricane conditions “could begin in the Hurricane Watch area late Friday,” and tropical storm conditions “could begin in the watches areas midday Friday.”

Storm surge heights by area

Advisory 4A says the water could reach these heights above ground somewhere in the indicated areas if the peak surge occurs at the time of high tide:

Ocean Springs, Mississippi, to Indian Pass, Florida: 5 to 7 feet
Mobile Bay: 5 to 7 feet
Mouth of the Mississippi River, Louisiana, to Ocean Springs, Mississippi: 3 to 5 feet
Indian Pass to the Aucilla River, Florida: 3 to 5 feet
Aucilla River to Yankeetown, Florida: 2 to 4 feet
Lake Pontchartrain: 1 to 3 feet

The advisory says the deepest water “will occur along the immediate coast near and to the east of the landfall location, where the surge will be accompanied by large and dangerous waves.” It also warns that surge flooding “depends on the relative timing of the surge and the tidal cycle, and can vary greatly over short distances.”

Rain and surf

For the Bay of Campeche coast, Advisory 4A forecasts 2 to 4 inches of rain through Thursday, with isolated higher amounts possible in the Mexican states of Campeche and western Yucatan.

From Friday through the weekend, it forecasts 3 to 6 inches across the central U.S. Gulf Coast, from far southeastern Louisiana to the Florida Panhandle, with localized totals up to 10 inches. Farther inland, 1 to 3 inches, with localized amounts up to 5 inches, are possible across much of the Southeast as far north as the Tennessee Valley and the Carolinas. The advisory says flash and urban flooding, along with isolated river flooding, will be possible.

Swells are expected to reach the western and northern Yucatan Peninsula starting Thursday and spread north toward the Gulf Coast late this week. The advisory says they “are likely to cause life-threatening surf and rip current conditions.”

How the forecast has changed since Advisory 1

Tropical Depression Nine is the system that became Isaias: Advisory 3 (4:00 a.m. CDT Wednesday) carried the headline “DEPRESSION BECOMES TROPICAL STORM ISAIAS.”

Advisory 1, 4:00 p.m. CDT Tuesday, Oct. 6 (5:00 p.m. EDT): Tropical Depression Nine, 35 mph, moving east at 5 mph, pressure 1007 mb, at 22.1 North, 95.6 West. The forecast was for it to become a tropical storm by early Wednesday and a hurricane on Thursday. No coastal watches were in effect.
Advisory 2, 10:00 p.m. CDT Tuesday: still a depression at 35 mph, pressure 1005 mb. No coastal watches.
Advisory 3, 4:00 a.m. CDT Wednesday: the depression became Tropical Storm Isaias, with winds of 40 mph and pressure 1004 mb. The headline said it was “forecast to rapidly strengthen over the next couple of days.” Hurricane Watches “will likely be required” later that day.
Advisory 4, 10:00 a.m. CDT Wednesday: winds 45 mph, pressure 1000 mb. Storm Surge, Hurricane and Tropical Storm Watches were issued.
Advisory 4A, 1:00 p.m. CDT Wednesday: winds 50 mph, pressure 997 mb, based on a dropsonde. Watches unchanged.

The hurricane-by-Thursday and Friday-approach timing has stayed the same across all of these. What changed is the storm’s strength, the coastal watches and a forecast track “nudged a bit eastward” from the previous advisory, according to the Advisory 4 discussion.

Why the track is still uncertain

The 10:00 a.m. CDT Advisory 4 forecast discussion says the storm should be steered by a trough along the northwestern Gulf coast and the subtropical ridge east of Florida building westward, which “should cause a fast-moving Isaias to approach the northern Gulf coast by Friday afternoon.”

It then says: “Model guidance continues to be somewhat split, with the AI-based models generally on the right side of the model envelope, and the physics based models on the left side.” In plain words, the models are somewhat split on how far east the storm tracks, with the AI-based models generally on the right (east) side of the envelope and the physics-based models generally on the left side, according to the NHC discussion.

The center’s forecast “is nudged a bit eastward,” the discussion says, but “isn’t as far east” as two of the consensus tools it names, the HFIP Corrected Consensus Approach and the Google DeepMind ensemble mean. The forecasters also note that “many of the stronger solutions tend to be on the eastern half of the guidance and faster, which necessitates a variety of watches at this time.”

On intensity, the same discussion says the center is re-forming a bit to the north and that this “could facilitate rapid intensification during the next day or two,” citing light-to-moderate wind shear, near-record sea surface temperatures for this time of year and a very moist environment. It adds that near landfall, increasing shear “could cause some weakening, but it isn’t certain how fast the winds will diminish.” The next sentence reads: “Regardless, Isaias should be growing in size as it approaches the northern Gulf coast due to a trough interaction.”

Florida’s state of emergency

Florida Gov. Ron DeSantis signed Executive Order 26-202, declaring a state of emergency in 25 counties: Baker, Bay, Calhoun, Columbia, Dixie, Escambia, Franklin, Gadsden, Gilchrist, Gulf, Hamilton, Holmes, Jackson, Jefferson, Lafayette, Leon, Liberty, Madison, Okaloosa, Santa Rosa, Suwannee, Taylor, Walton, Wakulla and Washington. The order was written for Tropical Depression Nine and cites the National Hurricane Center’s designation “as of 5:00 PM EDT on October 6, 2026.”

The order also says a stalled frontal system “has produced widespread heavy rainfall across portions of North Florida, with rainfall totals of approximately five to nine inches reported in some areas, resulting in saturated soils, elevated water levels, overwhelmed drainage systems, and an increased potential for flash flooding and riverine flooding.”

The governor’s office said in its release that the order lets the state Division of Emergency Management stage resources, and that they will be staged in Tallahassee and the Santa Rosa area. The governor is quoted in the release: “Floridians should take this time to get disaster plans in place and ensure their hurricane supply kit is stocked.”

What is not known

Whether more watches or warnings will be issued. Advisory 4A says they “could be required” later today. The next complete advisory is at 4 p.m. CDT (5 p.m. EDT).
Where and when Isaias will reach the coast. The advisories give an approach on Friday, not a landfall point.
What other states have done. The National Hurricane Center’s text and Florida’s release do not report on emergency actions in Louisiana, Mississippi or Alabama. The Alabama Emergency Management Agency published a meteorologist’s briefing dated 7:00 a.m. CDT Wednesday, before the watches were issued, saying impacts could reach parts of the state beginning Friday and that “NOW is the time to get prepared!” That briefing carries its own forecast and is not a National Hurricane Center product. Declarations, evacuation orders and school closures come from governors and local officials, and readers should check state and local emergency management for them.

What readers can do

The National Hurricane Center’s Advisory 4A says: “Interests in the Yucatan Peninsula of Mexico and elsewhere around the U.S. northern Gulf Coast should closely monitor the progress of this system.”

The 10:00 a.m. CDT Advisory 4 discussion says residents in the Storm Surge Watch area “should follow advice given by local officials and evacuate if told to do so.” For the Hurricane Watch area, it says residents “should prepare for the possibility of long-duration power outages.”

Advisory 4A says that for storm information specific to your area, including possible inland watches and warnings, you should “monitor products issued by your local National Weather Service forecast office.” The Florida governor’s release points readers to FloridaDisaster.org for preparation resources.