Wetand News

The Northwest is a place of great physical beauty and that allure extends to the sky. There is perhaps no better example than the lenticular and mountain-wave clouds that are frequently seen here.   The displays during the past several days have been extraordinary. During the recent days, I have viewed some stunning lenticulars (lens-shaped clouds) over Puget Sound, but the most impressive imagery has occurred west of peaks of the Cascades.  Let me show you a few produced by Mount Adams, provided by the most accomplished lenticular photographer of the region:  Darlisa Black.   And I will give you a bit of mountain-wave 101 as well. Here is a picture taken by Darlisa on Friday (looking north, west is to the left).   Look closely and you will see one lenticular right over Mount Adams, nearly symmetric over the peak.  That is often called a cap cloud , and it results from air being pushed up by the mountain until it reaches saturation (100% relative humidity).   Picture by Darlisa Black B

 On Sunday morning, a strong low center will cross the Columbia Bars near Astoria. (see forecast sea level pressure and wind at 10 PM Saturday). The Oregon coasts will see gusts to 70 mph, while the central Washington coast and Puget Sound will just get a little breeze.   Why the difference?  I explain why in my podcast.  And I also talk about the upcoming modest atmospheric river (see moisture transport forecast below for 5 PM Monday), which should bring heavy rain and snow to the Olympics and North Cascades. Moisture transport late Monday afternoon (red and whitish colors indicate large amounts) The 48-h precipitation totals through 5 AM Wednesday snow large enhancement by the terrain and a profound rainshadow around Sequim and Port Townsend. To listen to my podcast,  use the link below or access it through your favorite podcast service. Some major podcast servers:     Like the podcast? Support on Patreon 

  This winter has been one with a relative paucity of strong Pacific cyclones hitting our coast.   One reason for this is the persistent La Nina pattern, with high pressure over the eastern Pacific; this pattern is not favorable for good cyclogenesis (development of low-pressure systems) off our coast. But conditions will change later Saturday as a fairly strong storm approaches the northern Oregon coast.   To illustrate this for you, below is a sea-level pressure forecast for 10 PM Saturday.  An impressive low center (cyclone) is just off the northern Oregon coast, with an intense pressure gradient (difference) to the south and southwest of the low center.  You will note the very large pressure change along the Oregon coast, one that will produce wind gusts of 40-70 mph along the coast. A closer-in view of the predicted storm three hours early shows the classic oceanic storm structure.  This map below shows the sea level pressures and predicted wind gusts at 7 PM Saturday.    The str

  It is time to reveal the future--or at least the best forecast of it.    The coming month or so is probably going to be wetter and cooler than normal in the Pacific Northwest.   Snowpack will build in the mountains.  Our reservoirs will be topped off.  Worries about Northwest water supply and drought will fade, and I suspect the dryland farmers in eastern Washington will be relieved. We are in a La Nina period, where the central and eastern tropical Pacific is cooler than normal, and the associated winters and springs tend to be cooler and wetter than normal.   But there is more--something I have noticed over the years.  La Nina conditions tend to result in large ridges of high pressure over the eastern Pacific, as we have observed frequently during the past months (see example below for Sunday morning).  When the ridge is close to us, conditions tend to be cool and  dry, but if it shifts a bit to the west, disturbances can move southward, providing showers and snow.  That is happeni

Have you noticed?    Wind speeds are often (usually) stronger during the day.  And this has been very much true the last few days. To illustrate,  here are the winds for Thursday and Friday at the University of Washington (top panel) with solar radiation and time (UTC)  on the bottom panel.  Black lines are sustained winds and red dots are gusts.  Winds are considerably stronger during the afternoon when the sun is in the sky! And not to be western Washington centric, the same thing is observed over eastern Washington for the past two days, as illustrated by the winds at Moses Lake, within the Columbia River Basin. Sustained winds at Moses Lake So why are winds stronger during the day?   There are two reasons: 1.  Solar heating causes the lower atmosphere to mix in the vertical, bringing stronger winds down from aloft. 2.  Solar heating can produce local diurnal circulations, such as sea breezes and upslope flow on terrain that can enhance winds. (1) is the most important for the

 My new podcast is out (see below) and it includes two compelling topics.   In one segment,  I tell you where you can find the most skillful weather forecast. You have a lot of choices , from hundreds of smartphone weather apps, the forecasts built into your phone, and a large number of websites, newspapers, radio, and TV. A website is dedicated to answering this question, forecastadvisor.com, and I show you some of the results (see below for a sample).  I also explain some of the big technological shifts that have made better weather forecasting possible. Forecast Accuracy for Seattle I  also discuss the weekend forecast.  The big eastern Pacific ridge of high pressure is back (see below) the entire region will enjoy sunny skies, no precipitation and seasonal temperatures.  Perfect conditions for outdoor activities, bolstered by a rapidly lengthening day and a perceptibly stronger sun. A big, upper-level (500 hPa, 18,000 ft) ridge off the West Coast on Sunday morning To listen to my p

There are few environmental issues with more unsupported claims than the effects of global warming on sea-level rise.    And such incorrect information is particularly egregious here in the Pacific Northwest. One of the worst offenders is the Seattle Times, which published a problematic story this week.   A story that was internally inconsistent, full of obvious errors, and making claims that are hyperbolic at best. The Seattle Times claims include (all direct quotes): The Washington coast could see as much sea-level rise — 4 to 6 inches — in the next three decades as it did in the previous century. By the end of the century, the state could see nearly 3 feet in average sea-level rise, according to the new projections, a jump from 2 feet in past studies. King County is expecting 2 to 3 feet of sea-level rise — and up to 5 feet — by 2100. Seattle has seen more than 9 inches in sea level rise since 1899 based on measurements by a NOAA tide gauge located at Colman Dock, according to King