DISCUSSION: As Northern California experienced wildfires that burnt at a devilish pace, the smoke from these fires impacted lives and events farther south. The smoke drifted heavily to the south because of a strong ridge of high pressure aloft which brought a northerly flow, which picked up the smoke and transported it southwards. A subsidence inversion at about 3000 to 5000 feet also influenced the situation by keeping the smoke trapped at lower pressure levels.
The smoke from the wildfires was very noticeable in the San Francisco Bay Area. The Bay Area Air Quality Management District (BAAQMD) had issued daily Spare the Air alerts during the event and forecasted the air quality to be unhealthy for the entire Bay Area until about October 18th. School districts have issued statements that students will not be outside for Physical Education classes as well as recess. In addition, the California Interscholastic Federation’s Central Coast Section, San Francisco Section, and Oakland Section made decisions to postpone many athletic contests due to the health concerns affiliated with the smoke. Football was heavily affected by the sections’ decisions as a full weekend of games have been postponed to the end of the season, which, then pushed the playoffs back a week. Visibility was also affected at most airports at various parts of the week including San Francisco International where there were delays around 90 minutes and longer. In addition, there have been reports that ash has fallen from the skies to land on cars and buildings across parts of the Bay Area especially in San Francisco, Oakland, and Berkeley.
The Bay Area was not the only area affected by the smoke. The smoke had also reached the Central Valley region including Fresno. The smoke had much less of an effect although visibilities dropped at times to 1 mile in certain locations as well as some athletic events getting cancelled. However, they had fewer days of heavy smoke due to an off-shore flow from the northeast which kept the smoke out.
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© 2017 Meteorologist JP Kalb