Hurricane Norbert

Landfall | Summary
Posting Date: October 12, 2008, 5:55:00 AM

Hurricane Norbert surprised forecasters at the National Hurricane Center (NHC) yesterday. Rather than the continued weakening that had been forecast on Friday, Norbert gained strength and arrived on the southwest coast of Mexico's Baja Peninsula as a Category 2 hurricane. Maximum sustained winds at landfall were 105 mph. Norbert's intensity fluctuations over the last several days have kept forecasters busy. On Wednesday, Norbert had been a powerful Category 4 storm with winds of 135 mph. Just 24 hours later, Norbert underwent an eyewall replacement and weakened to a Category 2 hurricane. By Friday, satellite images showed a double eyewall and estimates of wind speed had dropped further to 85 mph—Category 1 on the Saffir-Simpson scale. Still, forecasters were openly acknowledging the considerable uncertainty in their estimates, given their derivation; aircraft reconnaissance missions in the Eastern Pacific are far less frequent than in the North Atlantic and intensity estimates are therefore largely satellite-derived. By 2:00 a.m. local time on Saturday, as it approached the coast of Baja, the NHC determined that Norbert was once again a major hurricane with sustained winds of 115 mph. But 6 hours later, satellite images showed a degradation of the eye and Norbert finally made landfall at about 9:30 a.m. local time (PDT) near Puerto Charley as a Category 2 storm. Fortunately, Norbert's landfall location was along a sparsely populated stretch of the coast about 145 miles northwest of the resort destination of Cabo San Lucas. Nevertheless, Norbert was a large system at landfall and homes in Puerto San Carlos, some 40 miles west-northwest of Puerto Charley, were reportedly knee-deep in water from the system's torrential rains. Roofs were blown off of homes and trees were downed in towns and villages across the region. Authorities evacuated hundreds of people from poorly constructed wood and sheet metal homes. However, AIR estimates that the take-up rate in this part of Mexico—that is, the percentage of properties actually insured against the hurricane peril—is quite low. Norbert maintained hurricane status as it crossed the Baja Penninsula and Gulf of California, making a second landfall in Mexico's Sonora state at around 8:00 p.m. local time as a Category 1 storm with maximum sustained winds of near 85 mph. While crops in Sonora and Sinaloa—the state adjacent and to the south of Sonora—are likely to suffer from Norbert's winds and rain, damage to insured properties in this largely agricultural and sparsely populated region is likely to be minimal. As Norbert continued its path inland, the Sierra Nevada mountain range quickly impacted the organization of the system, decoupling the surface-level circulation from the mid- and upper-level circulations. Norbert is now a tropical storm moving to the northeast at near 20 mph. After further weakening, the remnants of Norbert will be over northwest Mexico later this morning and over western Texas and New Mexico later today, which may receive up to 2 inches of rainfall. Given Norbert's landfall location and estimated take-up rates in the areas affected by this storm, AIR does not expect significant insured losses to onshore properties in Mexico.

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Posting Date: October 12, 2008, 5:55:00 AM