Pacific Hurricane Landfalls on Mexico and SST

Abstract

statistical model of northeastern Pacific Ocean tropical cyclones (TCs) is developed and used to estimate hurricane landfall rates along the coast of Mexico. Mean annual landfall rates for 1971?2014 are compared with mean rates for the extremely high northeastern Pacific sea surface temperature (SST) of 2015. Over the full coast, the mean rate and 5%?95% uncertainty range (in parentheses) for TCs that are category 1 and higher on the Saffir?Simpson scale (C1+ TCs) are 1.24 (1.05, 1.33) yr?1 for 1971?2014 and 1.69 (0.89, 2.08) yr?1 for 2015?a difference that is not significant. The increase for the most intense landfalls (category-5 TCs) is significant: 0.009 (0.006, 0.011) yr?1 for 1971?2014 and 0.031 (0.016, 0.036) yr?1 for 2015. The SST impact on the rate of category-5 TC landfalls is largest on the northern Mexican coast. The increased landfall rates for category-5 TCs are consistent with independent analysis showing that SST has its greatest impact on the formation rates of the most intense northeastern Pacific TCs. Landfall rates on Hawaii [0.033 (0.019, 0.045) yr?1 for C1+ TCs and 0.010 (0.005, 0.016) yr?1 for C3+ TCs for 1971?2014] show increases in the best estimates for 2015 conditions, but the changes are statistically insignificant.