Alberto makes landfall in Mexico while flooding parts of Texas coast

Alberto, the first named tropical storm of the 2024 Atlantic hurricane season, made landfall near Tampico, Mexico, on Thursday morning. The sprawling storm has unleashed strong winds and heavy rainfall in northeast Mexico and Texas while producing a significant ocean surge that stretched as far north as Louisiana, 700 miles from the storm’s center.

As of 11 a.m. Eastern time, the storm weakened to a depression about 95 miles west of Tampico. Earlier in the morning, Brownsville, Texas, reported a gust to 56 mph, and a gust to 54 mph was clocked at the mouth of Baffin Bay in Southeast Texas.

The Associated Press reported that flooding rains in northeast Mexico had left three people dead. Flash flooding will continue across Tamaulipas and northern Veracruz, Mexico, as well as South Texas, into the afternoon, with the potential for “considerable flash and urban flooding along with new and renewed river flooding,” according to the National Hurricane Center.

In Texas, while minimal wind damage has occurred inland, the persistent fetch of southeasterly winds has led to locally significant coastal flooding and a storm surge of 2 to 4 feet. Galveston Bay experienced its seventh-highest water level on record, and Rockport, Texas, saw its fourth-greatest surge. Sea levels have risen by about 1.6 feet since 1940, meaning the effects of human-caused climate change are exacerbating storm-driven flooding.

In Surfside Beach, a city in Brazoria County, Texas, on Follet’s Island, the majority of streets were inundated with a foot or more of ocean water, and homes – most of which were erected on stilts – had water beneath them. Surfside has an average elevation of 6.5 feet above sea level. Water levels reached 3.7 feet above normal Wednesday, and were still 2.7 feet above normal as of midmorning Thursday.

On extreme South Padre Island, water levels were still 2.5 feet above ordinary conditions to start the day Wednesday.

In addition to coastal surge, inland freshwater flooding has been of concern. Fortunately, flash flooding hasn’t been quite as significant as it could have been. A total of 7 inches was reported at the Welder Wildlife Foundation north of Corpus Christi, and nearby R.B. Farms tallied 6.87 inches. Bayside, to the north, had 6.81 inches, but the Corpus Christi International Airport was up to a comparatively tame 3.89 inches. That’s illustrative of the highly localized nature of tropical downpours.

Southwest of Corpus Christi, several residential roads were reportedly closed due to flooding. Bishop’s 48-hour rain total was 5.6 inches.

A weather balloon launched around 7 p.m. Wednesday evening from Corpus Christi found a nearly record-moist tropical air mass in place. It was found that every column of the lower atmosphere was holding 2.95 inches of moisture. That’s the second-greatest moisture content observed from a balloon release from Corpus Christi; the record is 3 inches, set July 1, 2010.

In Mexico, meanwhile, heavy rains have led to flooding along the Catarina River in Monterey. Tropical storm warnings in Mexico were discontinued, but the threat from heavy inland rain and flooding will continue.

What’s next for Alberto

As the system moves inland and becomes cut off from the warm Gulf of Mexico waters that sustain it, it will continue to weaken. That means the storm will begin to “fill in” with air (just like a whirlpool in your coffee cup will slowly return to equilibrium and spin more slowly), translating to lesser wind speeds.

That said, even as Alberto weakens, it will continue to dump its moisture. Although less than an inch of additional rainfall is forecast in South Texas, the Hurricane Center wrote that another 5 to 10 inches isn’t out of the question in parts of inland Mexico and up to 20 inches in the high terrain.

“Life-threatening flooding and mudslides are likely in and near areas of higher terrain across the Mexican states of Coahuila, Nuevo Leon, and Tamaulipas, including the cities of Monterrey and Ciudad Victoria,” the agency wrote.

Conditions are already improving in Texas, though lingering storm surge of up to several feet is possible in a few spots along with blustery onshore winds. In Mexico, residents will have to wait until Thursday night or Friday for a return to more tranquil weather.

Also in the tropics

In addition to the ongoing impacts associated with Alberto, meteorologists are tracking two additional disturbances in the Atlantic.

The first is a system about 150 miles east of the northern Bahamas; the National Hurricane Center has estimated a 40% chance of eventual development. Dry air is present near the system, presenting existing showers and thunderstorms from being more widespread. That said, there’s a 40 chance the system tightens into a tropical depression or storm, according to the Hurricane Center, as it meanders west toward Florida or Georgia, where some gusty showers are possible by early Friday.

Otherwise, a subtle disturbance in the western Caribbean will cross the Yucatán Peninsula and could develop in the Bay of Campeche; it has a 50% chance of development. It’s associated with the same broad swirl of low pressure that helped Alberto form. Similar parts of Mexico could again be affected late in the weekend or Monday.