Hurricane Dean had a central barometric pressure of 26.75 inches just before making landfall near the Mexico-Belize border early today. That made it the third-most-intense Atlantic hurricane at landfall since record-keeping began in the 1850s, according to the National Hurricane Center.

The air pressure in the eye of a hurricane is an indicator of a storm's ferocity because it's the low central pressure that powers the winds swirling around the eye, and the storm surge. 

The only storms with lower barometric readings at landfall were the unnamed 1935 Labor Day storm that ravaged the Florida Keys, with a pressure of 26.35 inches; and Hurricane Gilbert, which struck Mexico's Yucatan peninsula in 1988 with a central pressure of 26.22 inches.

The lowest barometric pressure ever recorded in an Atlantic hurricane was 26.05 inches, for Hurricane Wilma while at sea in 2005.

If Dean had made landfall in the United States, it would have ranked as the second-most intense ever to come ashore in the U.S., after the Labor Day storm in 1935. The next-most intense at landfall in the U.S. was Hurricane Camille, a deadly Category 5 storm that tore up the Gulf Coast of Louisiana and Mississippi in 1969. Its pressure at landfall was 26.84 inches.  

In the meantime, a weakened but still deadly Dean continues its trek across the Yucatan. Hurricane warnings are going up along the Mexican Gulf Coast. Here's the latest advisory. Here's the predicted storm track, and here's the satellite view.