This alert began 18 Aug 2023 10:00 GMT and is scheduled to expire 22 Aug 2023 23:59 GMT.
Source: Worldcue® Alert
Severity: Warning Alert
Environment: Hurricane Hilary tracking west-northwestward in the North Pacific Ocean early Aug. 18. Landfall over Baja California State, Mexico, Aug. 20.
- Event: Hurricane Hilary
- Affected Area(s): Western and northwestern Mexico; southwestern and western US (map)
- Projected Landfall (Date): Close approach to northwestern Baja California Sur (early Aug. 20); western Baja California (late Aug. 20)
- Center of Circulation: Approximately 640 km (400 miles) south of Cabo San Lucas, Baja California Sur State
- Maximum Sustained Winds: 125 knots (230 kph, 145 mph)
Summary
Hurricane Hilary has strengthened into a Category 4 hurricane and is tracking west-northwestward in the eastern North Pacific Ocean off the west coast of Mexico early Aug. 18. As of 03:00 MDT, the system's center of circulation was approximately 640 km (400 miles) south of Cabo San Lucas, Baja California Sur State.
Forecast models indicate that the storm will initially maintain Category 4 hurricane strength as it tracks northwestward and then north-northwestward off the coast of western Mexico Aug. 18-early Aug. 19, before weakening into a Category 3 hurricane as it approaches the Baja California Peninsula Aug. 19. The system is forecast to weaken further into a Category 2 and then Category 1 hurricane as it continues to track north-northwestward and passes close to far northwestern Baja California Sur early Aug. 20, before making landfall as a tropical storm over Ensenada Municipality in Baja California State late Aug. 20. Hilary is then forecast to weaken further into a tropical depression as it tracks generally northward across southern California and Nevada Aug. 21, before dissipating over southeastern Oregon early Aug. 22. Some uncertainty remains in the track and intensity forecast, and significant changes could occur over the coming hours.
As of early Aug. 18, authorities have issued the following coastal watches and warnings:
- Hurricane Watch: The Baja California Peninsula north of Punta Abreojos to San Jose de Las Palmas.
- Tropical Storm Warning: The Baja California Peninsula from Punta Abreojos southward and Loreto southward.
- Tropical Storm Watch: The Baja California Peninsula north of Loreto to Bahia de Los Angeles and mainland Mexico from Huatabampito to Bahia Kino in Sonora State.
Authorities will likely issue new warnings or update existing advisories throughout the system's progression in the coming hours and days.
Hurricane conditions are possible within the hurricane watch area by late Aug. 19-early Aug. 20. Tropical-storm-force winds are expected within the warnings and watch areas late Aug. 18-early Aug. 19. Rainfall totals of 7.5-15 cm (3-6 inches), with localized maximums of up to 20 cm (8 inches), are forecast across parts of the Baja California Peninsula through late Aug. 20. Similar rainfall amounts are expected in parts of southern California and southern Nevada through Aug. 21. Totals of 2.5-7.5 (1-3 inches) are forecast across other parts of the western US. Storm surge could produce coastal flooding along the western Baja California Peninsula where the storm approaches the coast. Large swells generated by Hilary, which are likely to cause life-threatening surf and rip current conditions, are forecast across parts of the southwest coast and the Baja California Peninsula over the coming days.
Sustained heavy rainfall could trigger flooding in low-lying areas and those with easily overwhelmed drainage systems. If weather conditions prove hazardous, localized evacuations, flash flooding, and landslides are possible.
The inclement weather could trigger localized business, transport, and utility disruptions and render some bridges or roadways impassable. Flight disruptions at regional airports and temporary closures of ports are also possible. Stagnant pools of water during and after flooding increase insect- and waterborne diseases, such as dengue fever, cholera, and malaria. Exposure to raw sewage and other hazardous materials mixed with floodwaters poses a serious health threat.
Advice
Activate contingency plans in areas where officials forecast tropical storm conditions. Heed any evacuation orders that may be issued. Use extreme caution in low-lying coastal areas and near streams, creeks, and other waterways due to the potential for severe flooding and storm surge. Stockpile water, batteries, and other essentials in advance. Charge battery-powered devices when electricity is available; restrict the use of cellular phones to emergencies only. Power down mobile devices when not in use. Keep important documents and necessary medications in waterproof containers. Observe strict food and water precautions, as municipalities could issue boil-water advisories following flooding events. Take precautions against insect- and waterborne diseases in the coming weeks.
Plan accordingly for protracted commercial, transport, and logistics disruptions in areas in the path of the storm, especially if vital infrastructure is damaged. Seek updated information on road conditions before driving or routing shipments through areas where flooding has occurred. Confirm flights before checking out of hotels or driving to the airport; clearing passenger backlogs may take several days in some locations.
Resources
US National Hurricane Center
Mexico National Meteorological Service (SMN)