Wetand News

As predicted, Arctic air started to move into the Northwest today, with the snow level dropping to several hundred feet above sea level.  Temperatures will be 10-15F below normal for much of the region over the next few days. Dr. Peter Benda's Home Around 1100 ft in Bellevue The 6 PM surface map show strong, cold northeasterly winds moving down through the Fraser River Valley into Northwest Washington, and temperatures in the 30sF and northerly winds pushing southward into Puget Sound Sound.  Cold northerly winds are also surging into eastern Washington. By tomorrow morning at 8 AM, unseasonably cold air will cover Washington (blue colors below), with a low center along the Oregon coast.  As a result, light snow will extend from Portland to Olympia in the west. The predicted snowfall totals through 5 PM tomorrow, shows very light snow from the the south Sound to Portland, and a half foot or so over the Cascades, including the eastern slopes. Temperatures will

See my new blog on this: >https://cliffmass.blogspot.com/2020/04/flying-blind-on-coronavirus-why-random.html Our society is now transitioning into panic about the coronavirus. Universities and schools are being shuttered, sports activities and public gatherings are being cancelled, individuals are hoarding toilet paper and supplies, travel is being severely constrained, the stock market has crashed, and business activity is nose-diving.  Major businesses are forcing their employees to work at home. This blog will try to summarize the coronavirus threat, suggest that some of the panic-driven actions may not be well-founded, and that there may be a far better, more effective approach to deal with the virus. Before I begin, let me note two things.   I am not a medical doctor, epidemiologist,  or viral expert. But I am a scientist with some facility with statistics and data, and my specialty, weather prediction, is all about helping people react appropriately to estimates

An unusual, and potentially damaging, mid-March cold blast will hit our region over the weekend.  Cold enough that there are concerns about crops in eastern Washington, particularly cherries. The sea level pressure and lower-atmosphere temperatures for 11 PM Friday (below) shows very cold air (purple colors) over BC and air cold enough to snow (blue colors) moving into eastern WA.  Importantly, a tight low center is found along the northern Oregon coast.  That will guarantee snow for someone west of the Cascades, depending on exactly the trajectory of the low.  By Sunday morning at 5 AM, cold air is predicted to surge southward over our region, with VERY cold air over eastern Washington.  You don't want to know about Montana. The models are suggesting that the morning lows from Saturday to Monday in places such as Yakima could get down to the mid to upper teens, 10-15F below normal.  This is very unusual and one can expect some daily minimum records to be broken, po

There is so much negative energy going around these days about the coronavirus and national politics, that is good to stand back and acknowledge the great beauty of our natural environment . Before sunrise, the Crystal Mountain cam showed Mt. Rainier, partially illuminated by a setting moon.  If you look careful, a cap cloud/lenticular is seen over the mountain's crest. The sunrise view from the Seattle Space Needle Panocam was gorgeous, with Mt. Rainier in the background.  To the east, there was some low-level clouds and fog.    With clear skies and very cold temperatures (many areas were below freezing), a good frosting was apparent in many locations. As the sun rose about the horizon, the low clouds starting streaming over the city--just stunning. But there was more.... a lot more to appreciate.    The Seattle Panocam image facing towards the Olympics around 8 AM showed a ring of light-- a glory -- surrounding the upper shadow of the Space Needle on the low c

Normally once we pass the first week of March, the lowlands are done with cold and snow. But not this year-- at least if the latest model forecasts are correct. Even this morning, unusually cold air aloft has brought some showers that produced some mixed rain and snow down to a few hundred feet, with snow reports from Clearview and Glacier, WA (click on link to view) The freezing level was roughly 1200 ft this morning, with the snow level about 1000 ft below.   With a strong spring sun, the ground is heating up, producing a large change in temperature with height, and thus an unstable atmosphere with towering cumulus clouds and showers. And some of these showers have ice pellets and few snow flakes. But the real potential action is late Friday and Saturday.  The latest UW high resolution forecast for Saturday morning at 8 AM is startling cold for mid-March, with the blue blue and purple colors in the forecast map below indicating a lower atmosphere cold enough for snow.   H

Every day I have been checking the weather radar for signs of the northward migration of our feathered friends, and Wednesday night I finally saw it. Ornithologists and those tracking the seasonal migration of birds have used weather radar for decades.  The radar signal of a target goes up rapidly with the size of the object (with the sixth power of the diameter) and thus a bird provides an immensely bigger signal than a raindrop. Many birds like to migrate at night, so a good sign of birds is a large area of radar return that starts around sunset and fades at sunrise.  Meteorological signals don't do that. And the birds prefer to stay over land--precipitation does not care much about the shoreline. So let me show you the birds... first at Portland. At 5:40 PM Wednesday, right before sunset, nothing much was apparent. By 6:41 PM, within an hour of sunset, echoes were appearing (reddish color), particularly NE of the city. In the middle of the night at 11:49

It is not that our region needs another health concern, but allergy suffers can attest to another challenge:    the surge of tree pollen during the past month.   But there is an interesting meteorological angle to be considered. The latest pollen.com forecast is for tomorrow (Thursday) to be a bad day, mainly from tree pollen. And the report Monday from the Northwest Asthma and Allergy Center showed the dominance of Cedar/Juniper pollen, with Alder in second place. But now to the meteorological angle.   Take a look at the pollen levels in Seattle over the past 30 days.  Up and down. Some days are very good, while others bring misery to the afflicted. But why? But why is this the case?  To explore the situation, I created a plot of Seattle pollen level and the precipitation at Boeing Field (see below).   Wow .  There is a very strong correlation between precipitation and low-levels of tree pollen, with rain really suppressing the pollen level. Local trees ar