Updated at the bottom with a theory from the air quality folks. First posted at 12:02 p.m.

We all know the Valley stinks (says the Westsider).

But this is ridiculous. Residents this morning began reporting a foul odor, something like rotten eggs, in the northern San Fernando Valley, the Valley's foothills, parts of Simi Valley and even the Inland Empire.

In fact immediate speculation was that the smell was coming from the Salton Sea in Riverside and Imperial counties, a constant source of rotten-egg stench. Maybe not, says the National Weather Service:

Forecaster Ryan Kaittell tells the Weekly that the weather pattern today doesn't support shifting a stink from the desert southeast of greater L.A. all the way to the Valley.

In fact he said the predominant winds have been from the ocean, first from the southwest and then from the north. That means the Valley's stench would be headed east, not vice-versa. Kaittell:

Credit: Corey Miller / Flickr

Credit: Corey Miller / Flickr

It would have to be a deep southeast flow to have anything like that. We don't have that now. … It doesn't seem feasible that it would be coming from there.

Nonetheless, at the same time Valleyites were calling 911 to report the funk (the L.A. Fire Department urges you not to do that — funk is not an emergency unless Rick James has risen from the dead), the Salton Sea's stench had apparently returned as well.

The Desert Sun speculates that the stench was unleashed via a desert thunderstorm last night:

The rotten-egg scent of the Salton Sea, released during last night's storm, has made its way across the desert and can be smelled, by some reports, as far as northern Los Angeles County.

Folks in the Coachella Valley to the north got a whiff, according to the paper, which would lend some credence to the idea of a stench flow.

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In any case, the LAFD states that the Air Quality Management District (AQMD) is looking into it. The department's Brian Humphrey:

There is no need to call 9-1-1 to report this widespread odor. LAFD will relay any official information from AQMD as soon as it becomes available.

Got that, people? Stink in the Valley is an everyday thing. Get back to work.

[Added at 1:53 p.m.]: The Los Angeles Daily News has created an interactive “Did You Smell It?” map, here.

[Update at 11:20 p.m.]: The South Coast AQMD tonight issued a statement saying that, while there's not definitive evidence that points to the Salton Sea, they think recent storm activity there released “strong, sulfur” odors.

Folks from the Coachella Valley, other parts of Riverside County, and sections of San Bernardino and Los Angeles counties reporting smelling the funk, according to the AQMD.

Other reports more specifically blamed an annual ritual of algae-choked fish that die and rot in the warm waters of the massive, man-made lake.

Barry Wallerstein, executive officer for the AQMD:

Several factors indicate that the Salton Sea may have been the source of these odors. However we do not have any definitive evidence to pinpoint the Salton Sea or any other source yet.

[@dennisjromero / djromero@laweekly.com / @LAWeeklyNews]

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