This is the first time on record that the Atlantic has had two hurricanes with winds of more than 150 miles per hour at the same time, Colorado State University meteorologist Philip Klotzbach said.
NHC noted that unsafe storm surge will raise water levels by as much as 5 to 7 feet above normal tide levels near and to the north of where Katia makes landfall.
The US National Hurricane Centre said that as a depression, Katia was blowing maximum sustained winds of almost 35 miles per hour and should dissipate over the mountains of central eastern Mexico later on Saturday.
Pena Nieto said the quake killed 45 people in the state of Oaxaca, 12 in Chiapas and four in Tabasco, on Mexico's Gulf Coast.
Mr Luis Felipe Puente, head of Mexico's national emergency services, has said that Katia had "worrying characteristics", as it was very slow-moving and could dump a lot of rain on areas that have been saturated in recent weeks. According to meteorologists, Hurricane Katia will cause serious damage in the center-north of the state of Veracruz.
The storm made landfall at South Padre Island, Texas, at midday (17.00GMT) as a category two hurricane, the National Hurricane Centre said, with the resort island practically submerged under the storm surge. In isolated parts of northern Veracruz, up to 25 inches of rain is possible.
As Katia was making landfall, Hurricane Irma, one of the most powerful Atlantic storms in a century, walloped Cuba's northern coast as a Category 5 storm.
Forecasters warned that Hurricane Katia could strengthen as it moves toward the coast of Mexico early Friday. Hurricane-force winds extend outward up to 10 miles (20 km) from the center and tropical-storm-force winds extend outward up to 60 miles (95 km).