Oregon hydrologist says early fall rains are 'a good start'
After an unprecedented and unexpectedly bad wildfire season this year, USDA hydrologist Scott Oviatt says a wet winter is definitely needed to prevent similar conflagrations in the future. "We've had extreme periods of very warm and dry weather," Oviatt said back in early September. "And we had that last winter, too. We had a very dry December and remained fairly dry and warm until March. This trend has been happening multiple years in the last decade, [and has led to] rapid melt out. Where we are today is pretty much the result. "What occurred was unprecedented, [and it involved] low humidity and dry conditions we typically don't see in summer or early fall."In early September, the previous water year was ending with less than desirable numbers. Precipitation for the region sat at 87% of normal – right before fires ignited all around the state.So far this fall, precipitation has picked up – but the intermittent dry spells occurring between showers are a concern."We've had substantial precipitation around Clackamas and Multnomah Counties," Oviatt now says. "We've established some early precipitation, which is good. Precipitation has been at 130% to 170% of normal since the wildfires, which is equivalent to about nine to eighteen inches of rainfall. Since the water year began on October 1st, we've received about 120% to 160% of normal precipitation amounts."While this early fall rain has been appreciated and needed, Oviatt says the jury is still out on what the water outlook will be for next spring, which will be determined by the precipitation and temperatures in the next few months. Conditions at this time last year looked very similar to our recent conditions. In October of 2019, the precipitation in the Hood, Sandy, and Lower Deschutes regions was around 120% to 140% of normal, which started the water year off well – but that was followed by a dry spell in November and December."This fall has definitely been a good start," Oviatt conceded. "Now we're in a holding pattern here. We hope we get a series of systems where we get consistent and sustained storm impacts. "Our weak point over the last 10 to 15 years has been extended dry periods in the winter. When that occurs, it prevents long-term precipitation build-up in the mountains, which leads to some concerns of potential water shortages in the spring. [Hopefully], we'll begin to get some fall rains and colder temperatures into winter."Since the new water year has just begun, Oviatt says he is "neither pessimistic nor optimistic" about this season moving forward."The main take-home point is we're still early in the water year, and a lot could change before January 1st. We're in a wait-and-see mode, and we're hoping for cooler temperatures," he concluded.As THE BEE went to press in mid-November the weather had, indeed, turned wetter and colder, raising hopes for a better winter than we had last year.
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