We really lucked out with our fire season west of the Cascades this year. After one of the driest springs and hottest/driest summers on record, vegetation was incredibly dry and the environment incredibly flammable. Mercifully, the last half of August were cooler-than-average, and September was both cooler and wetter-than-average. And most importantly, neither had dry thunderstorms to ignite fires or the dreaded offshore flow to turn existing blazes into raging firestorms, like we saw in September 2020.
The below graphs show the temperatures and precipitation compared to average for Sea-Tac this summer. Note how temperatures were generally well-above-average from mid/late June through the first half of August and how there was essentially no rain from mid June all the way through mid-September.
The cooler and wetter weather we’ve seen over the last month has done wonders for our short-term drought. The rivers are running much higher and cooler than they were at the beginning of September – fantastic news for the salmon headed up the rivers to spawn. And the grass in my neighborhood has changed from a dry brown to a deep green. It was thirsty!
The US drought monitor still shows severe, extreme, and even exceptional drought conditions over parts of the Pacific NW, particularly over Oregon and east of the Cascades. However, the drought monitor places more emphasis on long-term drought indicators, such as groundwater levels, well water depth, and reservoir storage. Regarding reservoir storage – most reservoirs in Washington have enough inflows to store the reservoir to their desired level even during drought conditions. However, reservoirs in California and Nevada, which have fewer inflows and greater demand, tend to be much more stressed.
Still have a long way with long-term drought, but the recent precipitation has resulted in significant short-term drought relief over the Pacific NW.
US Drought Monitor seems to emphasize long-term drought, hence the relatively slight improvement. #wawx #drought pic.twitter.com/oSmmSlsBCH
— Charlie Phillips (@GeoduckChuck) October 5, 2021
Forecast
Thankfully, our cool and wet pattern looks to continue for the foreseeable future! Take a look at the rain expected for the next 7 days over the Pacific Northwest. There’s even a good amount of rain for the Intermountain West and Desert SW as well! Unfortunately, models keep California mostly dry, but ensembles suggest that there’s a slight chance that some of the precipitation over the Pacific NW could reach down to the Bay Area.
Credit: University of Washington
Here in the Pacific NW, expect periods of rain today and showers Wednesday, with a weak front Friday night into Saturday. Thursday should be the nicest day of the week, with highs topping out in the mid/upper 50s under partly cloudy skies for those in the Puget Sound region.
The weather turns much cooler Sunday through next week as a deep trough slides SE from the Gulf of Alaska, opening us up to cool northwesterly flow.
Credit: UW
We’ve already seen some snow at Mt. Baker ski resort and Timberline Lodge this year, but I suspect next week will bring snow down to all the major passes, though it may have trouble sticking at Snoqualmie. But it’ll definitely get the skiers and boarders here hyped for the 2021-2022 season, if they weren’t already!
