The Wrath of Hilary: Swift Escalation to a Category 4 Hurricane

A satellite snapshot of Hurricane Hilary, taken on August 18, 2023, by the Visible Infrared Imaging Radiometer Suite (VIIRS) aboard NOAA-20, reveals the storm’s proximity to the Baja California peninsula. Hilary, now a Category 4 hurricane, is forecasted to deliver significant rainfall to Southern California, and warnings are in place in both Mexico and sections of the U.S.

Though initially predicted to lose strength before hitting Mexico and Southern California with heavy rainfall, the hurricane continues to be a major threat.

On August 18, 2023, Hurricane Hilary, classified as a category 4 storm in the Pacific Ocean, neared the Baja California peninsula.

Captured in the early hours of August 18 (09:25 Universal Time) by VIIRS on NOAA-20, the image of the hurricane’s eye was approximately 400 miles (640 kilometers) from the peninsula’s coast. The infrared brightness temperature data illustrated in the image helps differentiate the cooler cloud formations (in white and blue) from the warmer surfaces beneath (in yellow). Typically, the coldest temperatures correspond to the highest clouds.

Hilary’s Formation and Projected Route

Hilary’s maximum sustained winds were close to 145 miles (230 kilometers) per hour as of 9 a.m. Mountain Time (15:00 Universal Time) on August 18, per the National Hurricane Center. This puts it in the category 4 classification on the Saffir-Simpson wind scale. The storm originally formed as a tropical disturbance near Manzanillo, Mexico, on August 16, and rapidly intensified into a powerful category 4 hurricane between August 17 and August 18.

The National Hurricane Center anticipates that Hilary will head north-northwest, lose some power before reaching the peninsula’s center by August 19 evening, and then proceed inland over Southern California. Cities such as San Diego and Los Angeles are projected to experience heavy rain by August 20 evening. NASA’s Short-term Prediction Research and Transition Center (SPoRT) has noted that this heavy rain could oversaturate soil in the affected regions for several days post-storm.

Alerts and Safety Measures

The Mexican Government has declared a hurricane warning for the Baja California peninsula, covering the area from Punta Abreojos to Punta Eugenia. A tropical storm watch has been issued for parts of Southern California, including San Diego up to Huntington Beach, by the U.S. National Hurricane Center. This marks the first time such a watch has been announced for this region.

The NASA Earth Observatory image was created by Lauren Dauphin, using VIIRS data from NASA EOSDIS LANCE, GIBS/Worldview, and the Joint Polar Satellite System (JPSS).

Frequently Asked Questions (FAQs) about Hurricane Hilary

More about Hurricane Hilary

• National Hurricane Center
• NOAA-20 Satellite Information
• NASA’s Earth Observatory
• NASA’s Short-term Prediction Research and Transition Center (SPoRT)
• Saffir-Simpson Wind Scale
• Joint Polar Satellite System (JPSS)