Pasadena Windstorm

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The weather in the parts of California that most of us are familiar with is generally rather mild. Some of the hottest temperatures every recorded were in the Mojave Desert, but not many of us even know how to get there. Some of the heaviest snowfall ever recorded was near Tahoe, but many of us think of that as almost Nevada. San Jose, Los Angeles and the most populous regions enjoy mostly comfortable weather throughout they year.
‘Drought’ is often an inaccurate description of the naturally prolonged dry chaparral and desert weather, as if it is abnormal. There would be no chaparral or desert if it rained here as much as it does in other climates. What is considered to be normal rainfall in some regions would be disastrous to regions that do not normally get so much precipitation. Drought does happen here sometimes, but it is not as common as outsiders believe it to be.
Once in a while, we get something that really is strange. The floods and mudslides of the Winter of 1982 were disastrous. The wicked frosts of late 1990 were the worst in recorded history, even though they would not have been much of a problem in most other climates farther inland. On the morning of December 1 in 2011, Pasadena and the surrounding regions of the San Gabriel Valley experienced historically strong and destructive winds.
When I went to Los Angeles shortly afterward, I was amazed to see that pieces of the glass facades of some of the skyscrapers had been stripped away. Thrashed fronds of queen palms hung limply as if a hurricane had gone through. My colleague got these startling pictures of destroyed Canary Island date palms, which are famously resilient to wind, in Leimert Park, about fifteen miles southwest of Pasadena.

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Santa Ana Winds

P71221+They have been a part of life in Southern California longer than anyone can remember. The Santa Ana Winds have been blowing down from the high deserts to coastal plains long before people arrived in the region. They are arid and usually warm before they leave the Great Basin and Mojave Desert, and they get even warmer as they flow downhill through mountain passes. That is what makes them so dangerous during fire season. Wind alone accelerates wildfire. Warming arid wind desiccates fuel, making it more combustible before wildfire arrives.

Santa Ana Winds are so regular that they affect how tall trees grow within the regions of the mountain passes where Santa Ana Winds move the fastest. Tall Mexican fan palms that grew up straight where sheltered from wind near the ground innately lean with the prevailing wind as they grow up and become more exposed. Those closer to the narrow canyons lean the most. It is something that arborists recognize everywhere around the Los Angeles Basin. They can tell how strongly the Santa Ana Winds blow in any particular neighborhood by how Mexican fan palms lean.

Santa Ana Winds can be strong enough to break tree limbs, and blow trees down. In the past few days, they have been making quite a mess in the Los Angeles region; although not as much of a mess as they are making in conjunction with the Thomas Fire in Santa Barbara and Ventura Counties, which may already be the biggest wildfire in the modern history of California.

Overnight, Santa Ana Winds blew this California pepper tree onto a swimming pool in Los Angeles. Tree services, landscapers, gardeners and those who enjoy gardening will be busy cleaning up such problems for the next few days, as Santa Ana Winds continue.