Helene weakened to a tropical depression upon making landfall Saturday in northeastern Mexico, prompting authorities to cancel an earlier alert.
In its 10:00 a.m. bulletin, the Miami-based National Hurricane Center said Helene had been downgraded and had maximum sustained winds of 55 kilometers (35 miles) per hour.
The system, which on Friday had strengthened to become the eighth tropical storm of the Atlantic hurricane season, was moving toward the northwest at 15 kilometers (nine miles) per hour, the NHC said.
Mexico's government responded to the downgrade by canceling the alert it had issued for the coastal zone between Barra de Nautla, Veracruz state, and La Cruz, Tamaulipas.
NHC meteorologists said Helene is expected to continue moving in the same direction and the same speed as it further debilitates overland and could dissipate by early Monday.
Even so, it is forecast to drop up to 14 centimeters (5.5 inches) of rain in northern Veracruz state, the southern portion of Tamaulipas and the eastern region of San Luis Potosi state, and could trigger dangerous flooding and mudslides, the NHC said.
Helene made landfall a week after Ernesto battered southeastern Mexico as a Category 1 hurricane and a strong tropical storm, causing 12 deaths. EFE