Alberto, the first named storm of the Atlantic hurricane season, is bringing rain, wind and potential flooding to parts of Texas as it moves inland over Mexico. The system was downgraded from a tropical storm to a tropical depression on Thursday morning. 

Alberto has already been blamed for three deaths in Mexico. Authorities have said they hope the powerful system, which is forecast to bring as much as 20 inches of rain to some parts of Mexico, can relieve drought in the region as it moves west. 

Maps show the predicted path of the storm as it moves slowly across Mexico. 

Where is Tropical Depression Alberto headed? 

The National Hurricane Center’s forecast shows Alberto continuing west across Mexico, where it made landfall early Thursday morning. The storm is expected to continue inland as the day goes on. 

The storm is moving at a rate of about 13 miles per hour, the hurricane center said in a briefing, with maximum sustained winds of 45 miles per hour. As of late Thursday morning, Alberto was about 25 miles west of Tampico, Mexico, and 255 miles south of Brownsville, Texas. Rain was falling on both sides of the border. 

Tropical Depression Alberto is expected to dissipate as it moves across Mexico, the NHC said, forecasting that the storm will disappear sometime Thursday or overnight. The downgrade to a tropical depression is the first step in that process. 

Fifty-one Texas counties are under a disaster declaration as the storm moves across Mexico. 

Where will Tropical Depression Alberto bring rain and flooding? 

Maps from the National Hurricane Center show Alberto dropping rain across Mexico and parts of Texas. Photos and videos show flooded streets in the region. Wind and flooding conditions are expected to improve throughout the day, especially in Galveston and Corpus Christi.

Parts of Mexico near Tamaulipas could see between 12 and 16 inches of rain, according to the NHC. Broader swaths of the country, including much of the Veracruz and Oaxaca regions, were forecast to see up to four inches of rainfall. 

In the United States, the worst rain was expected near Laredo, Texas. The border city is in a region forecast to receive up to four inches of rain. Other parts of the state, including areas near Corpus Christi and San Antonio, could see up to two inches of rainfall. 

Other parts of Texas were prepared for storm surge and flooding. Much of the border and southeastern coast of Texas had at least a 5% chance of flash flooding, according to the NHC. In the Roswell area, there was at least a 15% risk of such flooding. 

Along Texas’ eastern coast, areas were bracing for storm surge of at least a foot. Between Sargent and the mouth of the Rio Grande, the NHC forecast a storm surge of between one and three feet. Similar storm surge was expected between Sabine Pass and the Vermilion/Cameron Parish Line. For the coastal area of Galveston Bay, the risk was even higher, with the NHC predicting a storm surge of between two and four feet.  

Kerry Breen

Kerry Breen is a news editor at CBSNews.com. A graduate of New York University’s Arthur L. Carter School of Journalism, she previously worked at NBC News’ TODAY Digital. She covers current events, breaking news and issues including substance use.