Hurricane Sergio will make a U-turn and push toward Baja California late next week, and its remnant moisture could once again trigger flooding in the Desert Southwest.
Sergio is currently hundreds of miles west of the Baja California coast in the eastern Pacific Ocean.
On Oct. 3, Sergio became the eighth Category 4 hurricane of the 2018 eastern Pacific hurricane season, topping a previous record of seven Category 4 hurricanes in an eastern Pacific season set in 2015, according to Eric Blake, a tropical scientist at the National Hurricane Center.
Usually, an eastern Pacific tropical cyclone moving west is of little concern for land impact. Simple geography, there.
In Sergio’s case, however, its steering winds are going to reverse.
Basically, high pressure aloft to its northwest is going to retreat, and a southward plunge of the jet stream near the West Coast of the U.S. takes over as the steering wheel for Sergio next week.
This will force Sergio to take a rather sharp U-turn in a few days.
This jet-stream plunge will also provide increasing wind shear, which, together with increasingly cooler ocean water, will weaken Sergio before it arrives in Baja California.
While Sergio will be greatly weakened by the time it heads into Baja California, it may have a more interesting future ahead as an inland remnant.
Sergio’s remnant spin above the surface and moisture may wring out more locally heavy rain in the Desert Southwest late next week as it sweeps northeast.
This could trigger more flash flooding, which unfortunately turned deadly from the remnants of another former eastern Pacific hurricane, Rosa, this past week.
Now here’s the strange part.
Some of that remnant moisture late next week may wrap into sufficiently cold air to bring yet more snow to the northern Rockies, on top of the snow they’ll receive the first half of the week.
So, you might say a remnant of a former hurricane may help produce snow.
This has happened before as recently as earlier this decade.
Almost six years ago, Superstorm Sandy had a largely forgotten snowy side, burying parts of the Appalachians in late October 2012.