Olaf (2021)

A tropical depression formed about 200 nautical miles (n mi) west-southwest of Manzanillo, Mexico on 7 September 2021 from a tropical wave and strengthened into Tropical Storm Olaf on 8 September. Olaf moved generally north-northwestward and rapidly intensified in a favorable environment, becoming a hurricane by 1200 UTC 9 September. The storm reached its peak strength as it approached and crossed the southern Baja California peninsula on 10 September, then weakened as it moved northwestward off the peninsula, became a tropical storm later that day, degenerated to a remnant low by 0600 UTC 11 September, and dissipated by 12 September.

Olaf made landfall on the southern tip of the Baja California peninsula near San José del Cabo at 0250 UTC 10 September 2021. It crossed the peninsula that morning, emerged over the eastern Pacific near Todos Santos around 0600 UTC 10 September, and passed near Puerto Cortes later that day before moving away from the coast.

The peak intensity at landfall was estimated at 90 kt (105 mph) maximum sustained winds with a minimum central pressure of 975 mb, corresponding to a Category 2 hurricane on the Saffir–Simpson scale. The best-track record lists 90 kt (approximately 105 mph) at 0250 UTC 10 September as the maximum winds and 975 mb as the lowest pressure.

Storm surge and heavy rain produced localized coastal flooding and significant rainfall totals on and near the southern Baja California peninsula. Reported rainfall highs included 9.27 inches (235.5 mm) at El Triunfo, 9.05 inches (229.8 mm) at La Ribera, and 7.68 inches (195 mm) at San Antonio. In mainland Mexico, parts of western Jalisco saw around 4 inches (~100 mm). Wind observations near landfall included a gust to 70 kt (80 mph) at a Cabo San Lucas marina and a gust to 81 kt (93 mph) at Cerritos Beach; many local observing sites lost power during the storm and more than 190,000 customers experienced outages.

Olaf caused one direct fatality in Jalisco resulting from a rain-triggered mudslide. Damage in southern Baja California Sur included flooding, downed trees and power lines, and impacts to hotels; media reports estimated about $10 million USD (≈200 million pesos) in damage, primarily in La Paz and Los Cabos.

Noteworthy items from the official analysis: genesis of Olaf was well anticipated by forecasts, but NHC track forecasts exhibited larger-than-normal errors early in the event and tended to be left of the observed track during the first 48 hours. Some forecast models (notably CTCI and GFSI) had stronger and more coast-ward solutions prior to landfall and outperformed the official track forecasts in this case.