Norma Prompts Hurricane Warning for Baja California

The potential risk posed by Hurricane Norma prompted the issuance of a Hurricane Warning for the southern part of Baja California. At 11:00 p.m. EDT on Thursday the center of Hurricane Norma was located at latitude 18.2°N and longitude 108.1°W which put it about 345 miles (555 km) south-southeast of Cabo San Lucas, Mexico. Norma was moving toward the north at 7 m.p.h. (11 km/h). The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 140 m.p.h. (220 km/h). The minimum surface pressure was 948 mb.

A Hurricane Warning was in effect for the portion of the coast from Todos Santos to Los Barriles, Mexico. The Hurricane Warning included Cabo San Lucas. A Tropical Storm Watch was in effect for Los Islas Marias. Tropical Storm Watches were also in effect for the portions of the coast from Todos Santos to Santa Fe, Mexico and from Los Barriles to La Paz, Mexico.

Hurricane Norma weakened slowly on Thursday evening. An upper level trough west of Baja California was producing southwesterly winds that were blowing toward the top of Norma’s circulation. Those winds were causing the vertical wind shear to increase. The eye at the center of Hurricane Norma was less distinct on satellite images. Bands of showers and thunderstorms were revolving around the core of Norma’s circulation. Storms near the core generated upper level divergence that pumped mass away from the hurricane.

Winds to hurricane force extended out 35 miles (55 km) from the center of Hurricane Norma. Winds to tropical storm force extended out 150 miles (240 km) from the center of Norma’s circulation. The Hurricane Intensity Index (HII) for Hurricane Norma was 22.1. The Hurricane Size Index (HSI) was 12.5 and the Hurricane Wind Intensity Size Index (HWISI) was 34.6. Hurricane Norma was similar in size and intensity to Hurricane Delta when Delta hit southwest Louisiana in 2020.

Hurricane Norma will move through an environment unfavorable for intensification during the next 24 hours. Norma will move over water where the Sea Surface Temperatures are near 29°C. However, the upper level trough west of Baja California will continue to produce southwesterly winds that will blow toward the top of Norma’s circulation. Those winds will cause moderate vertical wind shear. The wind shear will cause Hurricane Norma will to weaken during the next 24 hours.

Hurricane Norma will move around the western part of a high pressure system over Mexico. The high pressure system will steer Norma toward the north during the next 24 hours. On its anticipated track, Hurricane Norma could approach the southern end of Baja California on Friday night. Norma will bring strong winds and locally heavy rain to the southern end of Baja California. Heavy rain is likely to cause flash floods in some locations.