Wetand News

The Rocky Mountains,  a few hundred miles to our east, offer profound protection for our region from the bitter winter cold of the interior of North America. During the next week, this protective shield will be put to a severe test and will not be found wanting.  Let me show you. The terrain map below show the double terrain protection our region enjoys.  To the east are the Rockies, with plenty of terrain rising to 8000 to 10,000 ft.  To the east of the Rockies are the Great Plains of the interior of our continent, which provides a flat, low-elevation conduit from the frigid, snow covered Arctic directly into the middle of the continent. The Arctic is a particularly good place to generate cold air.   Covered with snow, which is a very effective emitter of infrared radiation to space.  Little solar radiation in winter.  Generally light winds and high pressure dominating.     Think of the Canadian Arctic and the nearby ice-covered ocean as the refrigerator for North America. But to dri

 My latest podcast is out.    I start with a review of this weekend's weather, with isolated showers on Saturday and more frequent precipitation on Sunday. Perhaps a half-foot of snow in the mountains. Then I turn to discussing the most dangerous weather feature of the region, the one that kills and injures more frequently than wind, floods, or anything else:  roadway icing . A foggy situation of great danger! I tell you what to look for and the foggy conditions that are most threatening. Here is my podcast: Click the play button to listen or use your favorite streaming service (see below) You can stream my podcast from your favorite services:   Listen on Apple Podcasts   Listen on Spotify Podcasts   Listen on Google Podcasts

 There are a lot of Blob enthusiasts in the Northwest and I wanted to provide an update on their favorite ocean/atmosphere feature. The Blob, as many of you know, is an area of persistent above-normal temperatures in the northeast Pacific.    The Blob has substantial impact on western Washington weather, tending to increase daily minimum temperatures, sometimes by as much as 2-8 F.   The Blob also has implications for local marine life, including the northward movement of subtropical marine species. If we take a look at sea surface temperature anomaly (difference from normal conditions or climatology) for last October, one can view a "healthy"  Blob off our coast, with portions 3-4 °C (6-8F) above normal, But by mid-December, the Blob had weakened considerably (no more red colors),  And by yesterday, it was quite anemic.  In fact, if you look closely, you will notice some blue colors (below-normal temperatures) along the West Coast and in the Gulf of Alaska. Why is the Blob w

Violence begets violence… violence is a descending spiral begetting the very thing it seeks to destroy, instead of diminishing evil, it multiplies it. –Dr. Martin Luther King A little over six months ago, I wrote a blog calling out political violence in Seattle. This blog, >Seattle: A City in Fear Can Be Restored , described the politically motivated violence on Seattle’s streets, its profoundly negative impact on the safety and lives of Seattle’s citizens, and noted the implicit support of the violence by local politicians. It was based on one of the most obvious lessons of history: that political violence begets political violence and thus can undermine or destabilize democratic societies. The blog was motivated by my concern for the future of Seattle, which is seriously threatened by both street violence and its tolerance by our current city leadership. I was also worried that political violence in Seattle and other cities could damage U.S civil society, weaken our political sy

  The winds are really blowing right now in central Puget Sound but are from an unusual direction:  easterly (from the east). Looking at the infrared satellite image for 5 PM today, you would expect lots of precipitation reaching the surface over western Washington, but only a few sprinkles have hit from Everett to Tacoma. This lack of precipitation i confirmed by the radar image at that time (see below).  And it was even precipitating and SNOWING on the coast.  How weird is that?  In fact, it IS snowing above us right now, but the snowflakes are evaporating before they reach the surface.  They don't have a chance. The explanation is the easterly flow, produced by a strong low-pressure center off our coast (see weather map at 4 PM below).  With high pressure inland and low pressure offshore, a powerful offshore directed pressure difference is in place, producing strong easterly winds. How strong?  Here is the plot of wind direction and gusts (red numbers) around the region (click o

 More snow is coming to our region late Tuesday and Wednesday, but Seattle snow lovers will be disappointed if they hope for snow in their backyards.   Substantial snow will be very close, but on the eastern sides of local terrain.  And the upcoming storm system will rapidly push southward, bringing welcome, heavy precipitation to drought-stricken California. The key feature is an approaching low pressure system, as shown by the forecast for Tuesday morning at 10 AM This offshore low, combined with high pressure inland, will create a large east-west pressure difference that will drive strong easterly (from the east) winds at low levels. And instead of moving eastward into Washington, the low will push southward towards California. The result of the easterly flow will be upslope flow and bountiful precipitation on the eastern sides of the Cascades, Olympics, and other region terrain features--the opposite of normal.   In contrast, the normally wet western slopes will be in the rainshado

The imagery from the Langley Hill radar near Hoquiam was quite extraordinary this morning.   At 10:10 AM there was a clear, precipitation-free "eye" with heavy precipitation bands circling around it as the feature came ashore near the the northern tip of the Long Beach peninsula. If it wasn't for the scale, would be wondering whether we were looking at the Gulf Coast in September!  And a close look a few minutes later showed the "eye" sliding eastward just south of Westport. This little "hurricane" packed some wallop, with eye associated with a small, intense  low pressure center and strong winds. Consider the situation at Toke Point (see map), where winds gusted to 40 knots (47 mph) at 1036 AM, dropped to 11 knots in the "eye" and rebounded  to 17 knots on the other side (see plot below). The sea level pressure plummeted to 1004 hPa (29.65 inches of mercury) at the center of the low. A surface map at 9 AM, shows the mini-low ready to move in

My new podcast is online (see below or the upper right to listen) and on it I examine the chances of snow this week and give you a short tutorial on western Washington snowstorms:  why are they so rare and what does it take to get decent snow west of the Cascades. Skies are clearing right now and expect sun and mid-40s the rest of the day. Tomorrow morning will be quite cold, with clear skies overnight allowing the Earth to radiate heat to space.  With a moist surface, we expect some fog and real threat of dangerous freezing fog. Sunday morning will bring some snowflakes to western WA but mainly above 500 ft.  Let me show you an interesting graphic that shows BOTH rain and snow.  Rain is shown by gray shades and snowfall by colors. For the 3 hours ending 4 AM Sunday, just rain over the lowlands, with snow up on the slopes. For the next three hours (through 7 AM Sunday), light snow on the hills and high elevation areas (such as north of Seattle to Everett, Cougar Mountain, southwest of