Pacific Hurricane Landfalls on Mexico and SST

A statistical model of Northeast Pacific 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 to mean rates for the extremely high Northeast Pacific sea-surface temperature (SST) of 2015. Over the full coast, the mean rate and 5%-95% uncertainty for Saffir-Simpson category one and higher TCs (category-1+ TCs) is ${1.24}_{1.05}^{1.33}{\text{yr}}^{-1}$ for 1971-2014 and ${1.69}_{0.89}^{2.08}{\text{yr}}^{-1}$ for 2015, a difference that is not significant. However, the increase for the most intense landfalls, category-5 TCs, is significant: ${0.009}_{0.006}^{0.011}{\text{yr}}^{-1}$ for 1971-2014 and ${0.031}_{0.016}^{0.036}{\text{yr}}^{-1}$ for 2015. The SST impact on the category-5 TC landfall rate is largest on the northern Mexican coast. The increased landfall rates for category-5 TCs is consistent with independent analysis showing that SST has its greatest impact on the formation rates of the most intense Northeast Pacific tropical cyclones. Landfall rates on Hawaii ( ${0.033}_{0.019}^{0.045}{\text{yr}}^{-1}$ for category-1+ TCs and ${0.010}_{0.005}^{0.016}{\text{yr}}^{-1}$ for category-3+ TCs for 1971-2014) show increases in the best estimates for 2015 conditions, but the changes are insignificant according to our tests.