Will there be a windstorm in the PNW on Christmas Eve?
Forecasters are dealing with a tricky scenario over the next day as a potential windstorm with high forecast uncertainty takes aim at the PNW. As of Tuesday morning, NWS Seattle has high wind watches in effect for both the coast and interior portions of western Washington. Much of western Oregon is under a wind advisory.…
Record breaking Christmas ridge, west coast remains stormy
We’ve finally reached the winter solstice but winter weather has been hard to come by. Much of the continental US is about to become trapped in a record breaking “omega block” patter that will bring record or near-record warmth to a large portion of the country just in time for Christmas. The classic manifestation of…
Is the slow start to snowpack season in Washington State part of a declining snowfall trend?
Summary: YES, early season snowpack has declined recently, even as season total snowfall and melt out dates remain essentially unchanged. Read on to learn more… In my previous post I showed that snowpack in Washington State is at or near record lows for early December at a number of sites while at the same time…
Historic river flooding as atmospheric river aims at Washington for a 4th consecutive day
It’s hard to put into words how extraordinary the ongoing atmospheric river event has been for western Washington. A 72-hour IR satellite loop shows how a band of moisture originating in the subtropics remained in place for nearly four straight days. As of Thursday morning, precipitation is finally beginning to taper off. A radar composite…
Two-part Atmospheric River event now underway
The “main event” is now underway in the PNW as radar on Monday morning shows broad coverage of light to moderate rain. Here’s the Langley (coastal WA) radar: The enhancement of the radar echoes as they move over terrain is clearly evident in this image. The moisture plume in atmospheric rivers is located fairly low…
Family of atmospheric rivers expected to cause high impact flooding in the PNW next week
It’s been a while since the PNW had a high impact extreme weather event. Rainy season so far has been mundane, with near-normal precipitation and no cold air to speak of. Unfortunately, cold air will continue to be absent for the next week while it appears that major river flooding is possible in the Washington…
Editorial: Devastating NOAA cuts must be fully reversed immediately
Along with nearly everyone in the atmospheric science community, I am gravely concerned that significant budget cuts and layoffs at NOAA will lead to irreparable harm to the United States. If upheld, these cuts will degrade the quality of weather data and forecasts in the US relative to other nations and cause greater death and…
How did Tuesday’s bomb cyclone trigger a major mountain wave windstorm over Seattle’s eastern suburbs?
Last Tuesday, a frontal cyclone rapidly deepened over the Pacific Ocean about 1,000 km to the west of Seattle. The storm was a “triple bomb”, meaning it reached around triple the 24 hPa in 24 hours threshold for explosive cyclogenesis, or “bombogenesis”. The minimum pressure reached about 945 hPa by Tuesday evening, one of the…
El Niño mostly to blame for low snowpack; La Niña transition expected by late summer
El Niño winters are generally known for being mild with low snowfall in the PNW. To date, the 2023-24 winter has been consistent with those expectations. Fortunately, some more favorable news came out last week that may have an impact on our weather in the months ahead. The NOAA Climate Prediction Center made news last…
Windy Tuesday, cold Thursday and Friday, and potentially an icy/snowy weekend
It didn’t take long for the PNW to experience what will likely go down as one of the most eventful weather weeks of 2024. As of Monday evening, the NWS Seattle homepage is full of a long list of weather warnings and advisories. The blizzard warning for the mountains is the first one issued by…
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