Hurricane Hilary Brings Wind and Rain to Baja California

Hurricane Hilary brought wind and rain to Baja California on Saturday night. At 11:00 p.m. EDT on Saturday the center of Hurricane Hilary was located at latitude 25.3°N and longitude 114.6°W which put it about 175 miles (280 km) south of Punta Eugenia, Mexico. Hilary was moving toward the north-northwest at 18 m.p.h. (30 km/h). The maximum sustained wind speed was 90 m.p.h. (145 km/h) and there were wind gusts to 105 m.p.h. (165 km/h). The minimum surface pressure was 968 mb.

Even though center of Hurricane Hilary was south of Punta Eugenia, Hilary brought strong winds and locally heavy rain to Baja California on Saturday night. A weather station in Loreto, Mexico reported a sustained wind speed of 58 m.p.h. (93 km/h) and a wind gust of 69 m.p.h. (111 km/h). There were reports of flash floods in Santa Rosalia, Mexico.

A Hurricane Warning was in effect for the portion of the coast from Punta Abreojos to Cabo San Quintin, Mexico. A Hurricane Watch was in effect for the portion of the coast from Cabo San Quintin to Ensenada, Mexico. A Tropical Storm Warning was in effect for the portion of the coast from Punta Abreojos to Todos Santos, Mexico. A Tropical Storm Warning was in effect for the portion of the coast from Los Barriles to Guaymas, Mexico. A Tropical Storm Warning was in effect for the portion of the coast from the U.S. border with Mexico to the Point Mugu, California. The Tropical Storm Warning included San Diego. The Tropical Storm Warning also included Catalina Island. A Tropical Storm Warning was in effect for the portion of the coast from Cabo San Quintin, Mexico to the border with the U.S. A Tropical Storm Watch was in effect for the portion of the coast from Guaymas to Huatabampito, Mexico.

Hurricane Hilary was weakening on Saturday night. There was no longer an eye visible on satellite images of Hurricane Hilary. The distribution of thunderstorms in Hilary was asymmetrical. Many of the thunderstorms were occurring in bands in the northern half of Hilary’s circulation. Bands in the southern half of the circulation consisted primarily of showers and lower clouds.

The circulation around Hurricane Hilary was still large even though Hilary was weakening. Winds to hurricane force extended out 45 miles (75 km) from the center of Hilary’s circulation. Winds to tropical storm force extended out 265 miles (425 km) from the center of circulation. The Hurricane Intensity Index (HII) was 13.9. The Hurricane Size Index (HSI) was 18.7 and the Hurricane Wind Intensity Size Index (HWISI) was 32.6. Hurricane Hilary was similar in size and intensity to Hurricane Matthew when Matthew hit South Carolina in 2016.

Hurricane Hilary will be moving into an environment that will be unfavorable for a hurricane during the next 24 hours. Hilary will move over water where the Sea Surface Temperatures are colder than 26°C. It will move between an upper level ridge over Mexico and the south central U.S. and an upper level low west of California. The upper level ridge and upper level low will interact to produce northerly winds that will blow toward the top of Hilary’s circulation. Those winds will cause the vertical wind shear to increase. The combination of cooler water and more vertical wind shear will cause Hurricane Hilary to weaken during the next 24 hours. In addition, much of the circulation in the eastern side of Hurricane Hilary will pass over Baja California. The mountains in Baja California will partially disrupt the flow of air around Hurricane Hilary.

The upper level ridge over the south central U.S. and the upper level low west of California will steer Hurricane Hilary toward the north-northwest during the next 24 hours. On its anticipated track, the center of Hurricane Hilary will be near Punta Eugenia early Sunday morning. Hilary will continue to produce strong, gusty winds and locally heavy rain in Baja California on Sunday. Heavy rain is likely to cause flash floods in some locations.

Hurricane Hilary could take a track similar to the one taken by Hurricane Nora in 1997. The center of Hilary will reach southern California by Sunday evening. Hilary will weaken to a tropical storm before it reaches southern California. Hilary will bring strong winds and locally heavy rain to parts of southern California. The heaviest rain is likely to fall where the wind force the air to rise over mountains. Heavy rain is likely to cause flash floods in some locations. Flood Watches have been issued for parts of southern California, southern Nevada, southern Utah and western Arizona. Hilary could also bring strong winds to mountains in southern Nevada, southern Utah and western Arizona.