Autumn forecast: Rain returning to Portland earlier, this year
Each fall Oregon forecasters produce a "What Will Winter Be Like" forum at OMSI; if social distancing precludes it being done at the museum's auditorium this year, we hope that it will at least take place online.
But this year, THE BEE has also received a forecast for Autumn along the West Coast – from the national "AccuWeather" private meteorological company. Of interest is their statement that the "La Niña" weather pattern seems to be returning to the central Pacific Ocean, which suggests a wetter, and possibly earlier, winter here than last year.
In early August they sent out this summary of their expectations for this fall on the West Coast:
Residents across the West Coast will face an elevated risk of wildfires heading into the new season, but the fire danger will be short-lived for the [northern] part of the region.
"This year, we are going to have an early-fall wildfire season in the Pacific Northwest," according to Paul Pastelok, a senior meteorologist who has been with AccuWeather for nearly three decades.
Pastelok pointed out that September is likely to be the most active month for wildfires across the Northwest, from about Eugene northward – an area where pockets of severe drought have developed. This has left brush and potential fuel drier than normal, one of the ingredients for destructive wildfires.
However, the active start to the wildfire season in the Northwest will last for only a few weeks, he says, before a wet pattern begins to set in by October, helping to put a lid on the larger fires that ignite in September and to shorten the overall length of the fire season.
"Definitely look for a shorter wildfire season in the Northwest, but still a strong one from places like eastern Washington, and mid-Oregon down into Northern California," Pastelok added.
Meanwhile, farther south in California, he says that it will take a longer time for the onset of the rainy season to arrive with storms being few and far between until the tail end of autumn and early winter. As a result, the fire season in Central and Southern California may well last quite a bit longer than it will in the Pacific Northwest.
October, in particular, is forecast to bring several Santa Ana Wind events, making it the busiest time for wildfires in Southern California – an area that has recently been scorched by huge late-season wildfires – and also an area where a huge fire in Riverside County was out of control even as that AccuWeather forecast was being issued.
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