As Hurricane Hilary gathers strength and barrels toward the southwestern United States, a sense of urgency is mounting due to the potential for prolific flooding rainfall, according to CNN.

This unfolding meteorological event has raised alarms across the region, culminating in the issuance of the first-ever tropical storm watch for California.

Hurricane Hilary's ominous forecast includes the alarming prospect of dumping more rainfall than a year's average across California, Nevada, and Arizona, with its trajectory aiming squarely at California's coastal areas.

Meteorological experts closely track Hurricane Hilary as it transitions from a powerful Category 4 hurricane, approximately 325 miles south of Cabo San Lucas, Mexico, to an imminent landfall in the southwestern US.

The storm's rapid intensification from a tropical storm to a Category 4 hurricane within 24 hours has heightened the concern.

The looming threat of a deluge has placed parts of California in an unusual and significant high-risk category for excessive rainfall.

In particular, Southern California faces a Level 4 out of 4 threat, indicating a rare and extreme possibility of torrential rains. Such a threat level has never been issued for this region, underscoring the gravity of the situation.

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Hurricane Hilary Potentially Hazardous to California, Southwest Regions, Says Expert

Stefanie Sullivan, a National Weather Service forecaster, emphasized that even as Hurricane Hilary is anticipated to weaken as it encounters colder waters en route to the US, the potential for residual impacts remains exceptionally hazardous.

A possible landfall in Southern California presents a disconcerting scenario where the region could experience up to 6 inches of rain within 48 hours, per The Independent.

Beaches, too, are likely to be battered by formidable waves, possibly reaching heights of 4 to 7 feet, alongside life-threatening currents.

Meteorologist Henry DiCarlo cautioned that while Hurricane Hilary may weaken to a tropical storm before it arrives in the US, its associated dangers, including strong winds and heavy rains, remain a looming concern.

DiCarlo anticipates that the storm's impact could be akin to a Category 1 hurricane, underscoring the severity of the expected weather event.

The hurricane's trajectory paints a broader concern across the southwestern US. Both the Baja California Peninsula and the southwest region of the US are at risk of encountering high winds and severe conditions.

The National Oceanic and Atmospheric Administration's National Hurricane Center alerted to the escalating potential for significant wind impacts, particularly in mountainous areas.

Tropical Storms Is Rare in California

The rare tropical storm occurrence in California is a stark reminder of the region's vulnerability to extreme weather events, NPR noted.

The West Coast's historical encounters with tropical storms and hurricanes are few and far between. The most notable instance occurred in 1858 when a hurricane brushed past San Diego with winds near hurricane strength.

A more recent memory dates back to 1939 when a tropical storm from a hurricane brought fatal flooding to Los Angeles and the Eastern Coachella Valley, killing 48 people and prompting a reevaluation of the region's preparedness.

Meanwhile, Hurricane Hilary's northward trajectory portends further trouble for the region.

As it moves inland from Southern California, it is poised to drench parts of southwestern Arizona and southern Nevada with heavy monsoonal rains.

The NWS has issued flood watches for Phoenix and Las Vegas, reflecting concerns over the possibility of up to 10 inches of rainfall in localized zones, a magnitude that surpasses the annual average.

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Written by: Bert Hoover

WATCH: Hurricane Hilary has strengthened a category four storm - From KTVB