- Tropical storm Hanna is headed for a landing in Texas on Saturday.
- The biggest danger is flooding the rain.
- Heavy local rains will spread across southern Texas to northeast Mexico.
- That strong local rain will persist long after making landfall.
- Tropical storm force winds are expected along and inland from the Texas coast.
- Strong waves and minor coastal flooding are expected along the northern and western Gulf coast.
Tropical storm Hanna formed in the Gulf of Mexico on Thursday night and is heading toward a landing in Texas on Saturday, with the potential for flash floods of dangerous rains spreading inland into northeast Mexico.
Hanna continues to strengthen slowly, but is expected to be known for her flood potential.
On Thursday night, the Hurricane Hunter reconnaissance mission found that the winds increased enough to improve Tropical Depression Eight to Tropical Storm Hanna, the eighth earliest record storm, beating the record for Tropical Storm Harvey, set in 2005, according to Phil Klotzbach, a tropical scientist at Colorado State University. Hanna was also formed before the previous record for the seventh earliest storm, beating the record set by Gert on July 24, 2005.
(PLUS: Why the 2020 season pales compared to the 2005 season)
The following map shows the latest tropical storm warnings and / or warnings issued. A watch means that tropical storm conditions are possible within 48 hours. A warning means that those conditions are expected in the next 36 hours.
Tropical storm clocks north of San Luis Pass, Texas have been discontinued.
Current watches and warnings
Tropical Storm Hanna is following the west-northwest toward the Gulf of Mexico toward Texas. Satellite images show that this system is producing increasingly concentrated thunderstorms, especially on its southern side. Slow additional strengthening is possible before it hits shore on Saturday.
Current information and projected route
Predicted impacts
Strong threat of rain
This will be the main concern with Hanna.
Some bands of Hanna’s showers and thunderstorms will spread to the coasts of Texas, Louisiana and Mississippi on Friday. A heavier rain can arrive along parts of the Texas coast overnight from Friday to Saturday morning and continue on Saturday as the center lands.
Current radar and satellite
(Clocks and warnings are issued by the National Weather Service.)
But as with most tropical cyclones, this will not be just a coastal event.
Heavy local rains will spread inland in southern Texas to parts of northeast Mexico. This heavy local rain could persist until Sunday, perhaps Monday, particularly in northeast Mexico.
Flash flood alerts have been issued for all of South Texas.
Rainfall totals of more than 5 inches are possible in these areas, with locally higher amounts where the rain bands stagnate for a period of a few hours. This could lead to dangerous flash floods and some river floods, particularly in the mountainous terrain of the Mexican states of Coahuila, Nuevo León, and northern Tamaulipas.
Rain forecast
(Heavier totals are possible when rain bands or groups of thunderstorms stagnate for a few hours, which could lead to local flash floods.)
Winds, coastal floods and storm surges
Tropical storm force winds could develop as early as tonight or Saturday morning and are most likely to be found along or near Texas Coastal Bend. These winds are capable of damaging some trees and sporadic power outages.
Tropical Storm Force Wind Chances
(The contours above show the possibility of tropical storm force winds (at least 39 mph), according to the latest forecast from the National Hurricane Center.)
Persistent onshore winds blowing east of Hanna can produce areas of high surf, rip currents, and possibly some minor coastal flooding at high tide, particularly along the northern Gulf Coast.
Coastal flooding closed the bridge along Cedar Lake Road in Biloxi, Mississippi on Thursday afternoon.
Some minor storms are expected from the Mexican border north to High Island, Texas, including Corpus Christi Bay, Matagorda Bay, and Galveston Bay. Water levels can rise up to 3 feet above the normally dry ground in this area at high tide.
Keep this in mind if you spend time on the beaches.
(PLUS: The danger of rip currents)
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