Tropical Storm Hilary made landfall along Mexico's Baja California coast on Sunday, with concerns growing about the potential for deadly flash flooding in Tijuana, Southern California, and even as far north as Idaho.

The storm hit a sparsely populated area south of Ensenada and has already caused flooding across Mexico's arid peninsula. Tijuana, known for its steep hillsides and improvised houses, is particularly vulnerable to mudslides.

#WATCH Floods in Palm Desert, Riverside County, #California 🇺🇸 Due to the effects of Tropical Storm Hilary. #PalmSprings #HurricaneHilary #Hurriquake #SoCalwx #Hurricane #HILARY #Califonia #BREAKINGNEWS #Breaking #HuracanHilary #HurricaneHilary #HurricaneHillary pic.twitter.com/zctvI00BLm

— Nitesh rathore (@niteshr813) August 21, 2023

Forecasters have warned of extreme flooding, mudslides, and tornadoes, with parts of the US Southwest expected to experience once-in-a-century rains. There is a possibility that Hilary could break records as the wettest known tropical cyclone in Nevada, Oregon, and Idaho. With sustained winds of 65 mph, Hilary continues to move northwest at 25 mph.

The Mexican cities of Ensenada and Tijuana have closed all beaches and opened several shelters at sports complexes and government offices. Michael Brennan, Director of the National Hurricane Center, emphasized the threat of rainfall flooding, which has proven to be the biggest killer in past tropical storms and hurricanes in the United States.

As Hilary approaches Southern California, light rain has already fallen across the region, soaking streets from Los Angeles to San Diego. Forecasters have issued tropical storm and potential flood warnings for Southern California, eastern Oregon, and Idaho.

Rainfall amounts of 3 to 6 inches are expected, with some areas potentially experiencing up to 10 inches. California Governor Gavin Newsom has declared a state of emergency, and the Federal Emergency Management Agency has dispatched officials and teams to provide assistance.

Hilary adds to the string of major climate disasters that have affected the US, Canada, and Mexico. In Hawaii, the deadliest US wildfire in over a century claimed over 100 lives and devastated the historic town of Lahaina on the island of Maui.

Meanwhile, Canada is facing its worst fire season on record. Hilary has caused significant damage along the Baja peninsula, including washed-out highways, power outages, and stranded residents. Evacuation warnings have been issued for Santa Catalina Island and several communities in San Bernardino County.

Authorities in Los Angeles are working to get the homeless population off the streets and into shelters, and state beaches in San Diego and Orange counties have been closed. As residents prepare for the storm, sandbags have run out and grocery store shelves are emptying. Joshua Tree National Park and Mojave National Preserve have also been closed to avoid visitors becoming stranded amid flooding.

President Joe Biden has urged everyone in the storm's path to take precautions and follow the guidance of state and local officials. Meanwhile, in the Atlantic Ocean, Tropical Storm Emily has formed and is moving west away from land.