Updated 11:22 PM ET
(AP) VERACRUZ, Mexico - Tropical Storm Helene formed just offshore in the southwestern Gulf of Mexico on Friday, threatening coastal areas of eastern Mexico where thousands of people are still recovering from flooding spawned by Hurricane Ernesto.
The U.S. National Hurricane Center said Helene was barely a tropical storm by late Friday but could strengthen again before making an expected landfall Saturday.
The storm was centered about 65 miles (105 kilometers) east of Tuxpan. It had maximum sustained winds of 40 mph and was moving northwest at 7 mph (11 kph).
Helene was forecast to make landfall in the northern part of Veracruz, a lush coastal state with hundreds of towns and villages sitting along streams and rivers that can swell dangerously in heavy rain. Many were evacuated during Ernesto, which hit last week, and some 10,000 were left homeless.
Mexico's government declared a state of emergency in more than 100 population centers in Veracruz and was providing them with emergency aid. The country's national weather service warned of intense rains and winds along the Veracruz and Tamaulipas coasts, with heavy rain, hail and lightning possible.
Helene was predicted to bring 5 to 10 inches of rain, with as many as 15 inches across northeastern portions of Mexico. A storm surge could raise water levels by as much as 1 to 2 feet above normal along the immediate coast and to the north of where landfall is made.
Heavy rain was expected in the city of Tampico, an oil-refining center and important port in the southernmost part of Tamaulipas state. The Tampico metropolitan area has roughly 790,000 inhabitants, sits just above sea level and is surrounded by lakes and lagoons that are already full and could easily flood in the event of heavy rains.
Civil protection authorities in Veracruz issued a yellow alert, one level below the highest warning, for population centers in the north and center of the state, warning residents to familiarize themselves with the locations of emergency shelters, avoid crossing swollen streams and rivers, and keep listening to radio and TV for storm updates.
Meanwhile, Portugal posted a tropical storm watch for the central and eastern Azores islands as Tropical Storm Gordon moved eastward across the Atlantic.