Bay Area

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KRON4 meteorologist Dave Spahr said the cause of the out-of-the-park reactions is twofold. First is the recent weather: late-season rains followed by bright sun. “Everything is growing like crazy,” he said. 

The second piece is that the atmosphere is not flushing out the high pollen counts produced by the combination of heavy rain and shining sun. “We’ve had local winds but not synoptic ones,” he said, referring to regional winds that create more movement. Fog alone, Spahr explained, is not enough to sweep the environment free of allergens.