When Southern California's Near-Perfect Climate Disappoints: Extreme Weather in L.A.

How many people has climate lured to Southern California? Idyllic images of a sun-drenched region – packaged into travel narratives, citrus crate labels, and surf-rock songs – attracted millions to the Los Angeles area. As early as the 1870s, tubercular invalids were moving to the region for its dry air and mild temperatures. Weather has been an essential part of the booster message ever since.

That booster message is prone to excess, and yet reality usually seems to confirm the promotional claims. Ocean breezes off the aptly-named Pacific temper the heat of summer and the cold of winter. A ring of inland mountains shelters the region from the extreme weather patterns of the continental interior. And a high-pressure ridge that reliably parks itself above the Pacific each spring keeps the Southland sunny and dry in summer.

How good is L.A.'s weather? Consider that Dodger Stadium last endured a rainout on April 17, 2000 – and rain has never canceled a game there during the months of June and July, when dark thunderstorms often menace East Coast ballparks.

Yes, L.A.'s weather is nearly perfect – except when it isn't.

Santa Ana winds blow hot in the fall. In winter sporadic yet intense Pacific storms threaten to overwhelm the Southland's colossal flood control system. And tornados form over Los Angeles with same frequency seen in the Great Plains; Mike Davis devoted an entire chapter of his book Ecology of Fear to "Our Secret Kansas."

Even the region's typical, stable weather pattern can disappoint and annoy. For some 260 days a year, an inversion ceiling hovers over the Los Angeles Basin, acting as an atmospheric lid. On good days, the resulting weather prompts complaints about "May Gray" or "June Gloom." On bad days, it prompts a smog alert.

Some events Snow once fell on downtown Los Angeles with more regularity but has not been observed by the city's official weather station since Jan. 22, 1962. (Blame the urban heat island effect, perhaps, and a warming climate?) Tropical 

• Last snowfall: Jan. 22, 1962.
• Last tropical storm: Sept. 25, 1939.
• Highest recorded temperature: 113 degrees on Sept. 27, 2010.
• Lowest recorded temperature:

This story was originally published on Jan. 27, 2011, as "Snow in the Basin: Documenting the Extremes of SoCal Weather." It has been extensively revised.