The world’s weather continues to concern, with record-breaking heat, wildfires and unprecedented storms on almost every continent.
It’s now the turn of the US west coast, where Tropical Storm Hilary has drifted on Sunday evening local time.
Cyclone-level storms are uncommon on North America’s west coast because the surface of the Pacific Ocean is usually too cool to maintain the energy required for hurricanes.
This year’s record-breaking heat, however, has created a rise in ocean temperatures which has allowed Hilary to form near Mexico and move north, and to be sustained.
Hurricane Hilary made landfall Sunday morning on the Baja California peninsula in Mexico on Sunday morning local time. The storm crossed the US-Mexico border that evening after weaking, being downgraded to a tropical storm. While downgraded, Hilary’s wind speeds are still over 100 km/h.
Tropical Storm Hilary has already killed at least one man in Santa Rosalía, Mexico after a car carrying 5 passengers was swept off the road.
Residents of California’s Channel Islands, home to thousands of people, have been ordered to evacuate.
Flooding has caused havoc on the dry, arid region which does not usually experience high rainfall.
“We are not used to this level of precipitation, generally. Certainly not in the middle of summer,” San Diego Mayor Todd Gloria told CNN, raising concern over power outages and flooding. “We’re not built for this kind of rainfall.”
The US National Weather Service warned on social media of “dangerous” and “life threatening” flooding to be expected.
Desert resort city Palm Springs saw more than 50 mm of rain in just six hours. The city’s average annual rainfall is about 140 mm or less. Rainfall across the Los Angeles area was between 20 and 75 mm on Sunday, turning roads into streams.
California Governor Gavin Newsom declared a state of emergency on Saturday and officials have warned that the “worst is yet to come.”
Hilary is the eighth named storm of the 2023 Pacific hurricane season. The season starts every year on May 15 in the eastern Pacific and on June 1 in the central Pacific, and ends on November 30.
If it hadn’t weakened, Hilary would have been the first hurricane to hit California since 1939. That storm killed nearly 100 people, caused blackouts and cut phones.
Unfortunately, according to The Weather Channel, the rain won’t be enough to stifle the fires raging throughout British Columbia in Canada, which have forced thousands to flee their homes.
Originally published by Cosmos as Tropical Storm Hilary: “We’re not built for this kind of rainfall”
Evrim Yazgin
Evrim Yazgin has a Bachelor of Science majoring in mathematical physics and a Master of Science in physics, both from the University of Melbourne.
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