Hurricane “Hilary” [Eastern Pacific]

[GordMay]

Tropical Storm “Hilary” crossed the US-Mexico border, into California, Sunday evening, local time, becoming the first tropical storm in the state, since “Nora”, in 1997.
As of 11 p.m. local time, the core of TS “Hilary” was roughly 10 miles southeast of Los Angeles, with winds of up to 45 miles per hour.
The storm could potentially be the first tropical system, on record, to strike Nevada, bringing up to 10 inches of rain, in some areas.

More ➥ https://www.wpc.ncep.noaa.gov/discus...hp?disc=pmdspd

****

Southern California residents were also struck by a more familiar phenomenon, Sunday, at 2:41 p.m local [21:41:00 UTC]: a magnitude 5.1 earthquake.
The epicenter of the quake was in Ojai, between Santa Barbara and Ventura, and it occurred along the Sisar fault, USGS data showed.
At least two aftershocks — measuring 3.1 and 3.6 — followed the initial quake.
There were no immediate reports of damage, or imnjury.

M 5.1 - 7 km SE of Ojai, CA ➥ https://earthquake.usgs.gov/earthqua...5386/executive

[GordMay]

Hilary was downgraded, to a tropical storm. a few hours before making landfall, as rain from the storm started spreading in Southern California.
Then it was downgraded again, to a subtropical cyclone.
As of 5 a.m. ET Monday, Hilary was some 390 miles north of San Diego, 75 miles northeast of Bakersfield, Calif., and racing north at 29 mph, with maximum sustained winds of 35 mph.

Key messages ➥ https://www.nhc.noaa.gov/refresh/gra...sages#contents

[GordMay]

After a year of weather extremes, in California and the US west, including record-breaking winter rain and snowfall, and punishing summer heatwaves,
Tropical Storm ‘Hilary’ made history, becoming the first storm, of its kind, to enter California, since 1997.

The state rarely sees landfalling tropical cyclones or hurricanes, thanks to a confluence of cold water [California current], and unfavorable atmospheric conditions [prevailing Easterlies] off the coast. The downward flow of air, across the state, also tends to squash down storms.
Experts say this occurrence will likely remain relatively rare, even as the climate changes.

‘Hilary’ formed in an area south of Baja California, and west of Mexico. Many storms form in the Eastern Pacific there, but most move harmlessly west, into the open Pacific, or into Mexico and then eventually [weaker] into the U.S. Southwest.
It’s one of the most active birthing places for tropical cyclones.

For a storm to intensify, the way ‘Hilary’ did, everything has to be ideal. There has to be warm water, it has to run deep, and there has to be little to no crosswinds [wind shear] decapitating the storm.
‘Hilary’ checked all those boxes.

Record high Pacific temperatures helped power the storm, and the combination of a low pressure area, along the west coast, and a high pressure ridge [heat dome], in the central US helped pull it northward, through the United States, instead of veering back out to sea.


Though the warm temperatures, and the heat dome didn’t cause ‘Hilary’ to form [that happened thousands of miles away, in the Eastern Pacific] it helped determine Hilary’s path.

Hurricanes need warm water to sustain their strength, and water temperatures, off the California coast, are typically too cold, due to the California Current, which flows south along the West Coast of North America.
The waters around northern Mexico have been abnormally warm recently — as much as 3 to 6 degrees Fahrenheit higher than average — allowing the storm to rapidly intensify, and maintain its strength, for longer than usual.
The water was warm, both, because of the natural El Niño, a warming of parts of the equatorial Pacific, and because of long-term climate change, that has been shattering records for heat, deeper in the oceans

Prevailing east-blowing winds also tend to steer tropical cyclones away from the California coast, and back out to sea. The region’s typical easterly winds have, temporarily, vanished.

A high-pressure [heat dome] system sitting over the central U.S., combined with a low-pressure system off the California coast, redirected winds northward, rather than eastward, helping steer Hilary up the coast, instead of veering back out to sea.

High-pressure air moves clockwise, acting like a conveyor belt, bringing ‘Hilary’ up the West Coast, and in toward California and Nevada.
A trough in the jet stream, over California also grabbed ‘Hilary’, and pulled it northward, as well as helping cause the storm’s precipitation.

So ‘Hilary’ rapidly intensified, gaining 75 mph in wind speed strength, in just 24 hours [more than double the rate that defines rapid intensification].
Recently, we’ve been seeing more and more rapid intensification, according to a 2019 study [1 & 2], showing this phenomenon increasing.
In the day-to-day changing weather, for individual storms, the wind issue is important, but over the decades that the team studied, water temperature was a far bigger factor.

A 2022 study [3] showed how warming has increased extreme rainfall, from hurricanes.

[1] “Recent increases in tropical cyclone intensification rates” ~ by Kieran T. Bhatia et al
➥ https://www.nature.com/articles/s41467-019-08471-z

[2] “Trends in Global Tropical Cyclone Activity: 1990–2021" ~ by Philip J. Klotzbach et al
➥ https://agupubs.onlinelibrary.wiley....9/2021GL095774


[3] “Attribution of 2020 hurricane season extreme rainfall to human-induced climate change” ~ by Kevin A. Reed et al
➥ https://www.nature.com/articles/s41467-022-29379-1

[boatman61]

On the bright side I hear the three year water shortage has ended..

[GordMay]

Originally Posted by boatman61

On the bright side I hear the three year water shortage has ended..

Sort of - but not quite, even though they've lifted water [some?] restrictions.
In California, water shortages aren't just due to a lack of rain/snow, and the state's chronic water problems are far from over, as the state’s farms and cities are still using far more water, than is available.
California's groundwater/aquifer drought is still bad.
The Colorado River, California's other major water source, is still in drought.

[GordMay]

Boatie's jest has some truth to it.

Lake Mead Water Level

Thanks to tropical storm 'Hilary', Lake Mead's water levels are at the highest point, this year.
Lake Mead is currently at 1,064.15 feet above mean sea level, but still well below full pool.
➥ https://mead.uslakes.info/level.asp

On June 5th, water levels at the Colorado River reservoir were at 1,054.42 feet.
Last year the water levels reached the lowest level seen since the 1930s, with the water line at a mere 1,040 feet [about 27% of capacity].

At maximum capacity [“full pool”], Lake Mead would reach an elevation 1,229 feet, near the dam, and would hold 9.3 trillion gallons of water. The lake last approached full capacity, in the summers of 1983 and 1999.

The increase in water levels, at Lake Mead, began in late April, thanks, in part, to the Bureau of Reclamation releasing a tremendous amount of water from Lake Powell.
It is hoped that Lake Powell may rise 65 feet, and Lake Mead 10-15 feet, this summer.

This increase in water levels is most likely temporary, and during the next drought, the water levels will likely plummet, once again.

[SomeGuyInaShirt]

I just got in from offshore so I had no idea the impacts of this storm. Does anyone know what I can expect to encounter when I'm in California and Baja Mexico? Ironically I cut my passage from Neah Bay to San Francisco short due to light winds. I'm in Oregon now thinking if heading back out very soon.

Was planning on hanging out in La Paz when I get there so hopefully it's not destroyed.

[Letterkenny]

Originally Posted by SomeGuyInaShirt

I just got in from offshore so I had no idea the impacts of this storm. Does anyone know what I can expect to encounter when I'm in California and Baja Mexico? Ironically I cut my passage from Neah Bay to San Francisco short due to light winds. I'm in Oregon now thinking if heading back out very soon.

Was planning on hanging out in La Paz when I get there so hopefully it's not destroyed.

Not sure further south but in San Diego, it’s business as usual and no impact.

[donradcliffe]

On the grand scale of things, hurricane damage is limited to local areas, On the weather map, Hilary hit Turtle Bay hard, but I have not been able to get any damage reports.

[SomeGuyInaShirt]

Originally Posted by Letterkenny

Not sure further south but in San Diego, it’s business as usual and no impact.

A Letterkenny fan In San Diego? Do you ever visit....Elleeeeh?😆

Thanks for the info ✌🏻

[SomeGuyInaShirt]

Originally Posted by donradcliffe

On the grand scale of things, hurricane damage is limited to local areas, On the weather map, Hilary hit Turtle Bay hard, but I have not been able to get any damage reports.

Hopefully they weathered the storm well 😐

Thanks for the info ✌🏻

[sv_pelagia]

La Paz not "hit" by hurricane... this time.

[SomeGuyInaShirt]

Originally Posted by sv_pelagia

La Paz not "hit" by hurricane... this time.

Excellent, it sounds like a great place for cruisers to hang out