Saturday, October 14, 2017

Cold Weather and Snow Hits the Pacific Northwest

Snow has hit the Cascade passes and below-normal temperatures have spread over the Pacific Northwest, with temperatures dropping into the single digits in portions of eastern Oregon.

And ironically such cold temperatures are a bad sign for those battling the wildfires north of San Francisco.

To "warm up" this blog, lets start with the latest cam shots at Snoqualmie and Stevens Passes.  White stuff.  Enough to make folks think about the upcoming winter season (which may be a good one because of La Nina).




During the last day, many NW folks have observed frost, with temperatures dropping below freezing on both sides of the Cascades.  The map of minimum temperatures for the 24-h ending 8 AM Saturday (below, click to expand), shows 20s in eastern Washington, with teens and even single digits in the valleys of the high plateau of Oregon.  Klamath Marsh RAWS site east of Crater Lake dropped to 5F and Burns, Oregon set a new record for the date (10F).


The below-normal temperatures were clearly evident at Sea Tac and Pasco, WA--here are plots for the past two days at these locations, with average maxima (purple) and minima (light blue).    At Sea-Tac, Thursday was crazy cold (about 12F below normal) and this mornings low temperatures were clearly the coldest so far this fall.
And many days dropping below normal at Pasco.
The air morning into our region is near record cold, something shown by comparing the incoming temperature at 5000 ft (850 hPa) at Quillayute (Wa coast) with climatology (see below).  The gray dot shows the observation at 5 PM Friday and the blue line shows the record low for the date.

The cold air that moved into the Pacific Northwest is associated with higher pressure, something shown by the 12-h forecast for 5 AM today (Saturday) for sea level pressure (solid lines) and lower atmosphere temperature (color shading).  At the leading edge of the cold/high pressure there is a large change in pressure (pressure gradient) that is associated with strong winds.  Unfortunately, some of that pressure-change zone is now over northern CA, which is revving up the winds, particularly over the northern Sierra.   Not as bad as Sunday/Monday, but enough to bring concerns of reinvigorated fires.


The winds yesterday were mostly northerly (from the north) over northern CA, and that blew the smoke southward toward San Francisco (see MODIS image).


I am working on an analysis of winds during this fire event, particular an evaluation of how unusual they were...stay tuned.

15 comments:

Stephen Fry said...

Thanks Cliff for your post. NASA just reported that drought/high temperatures (e.g. in Asia, Africa & S America) associated with El Nino and climate change resulted in a recent historic jump in earth's CO2 emissions & concentrations. Apparently the trees are in a dehydrated state and can't extract the CO2 from the atmosphere as well. We need a complete world war on global warming to protect our planet, including building a multitude of large drones to fight wildfires, promptly converting the transportation system to electric-powered, and using clean energy to heat and power our civilizations. Otherwise, it looks like we in for a hot, smoky and hazardous future.

evie said...

Ahhhh! Cold temps. Snow at pass level. Make my day/week/month/year. Tell me we are going to enjoy snow in the lowlands this winter.

Eric Blair said...

Thank you for that reasoned and not - at - all - hysterical argument, Stephen. No doubt after reading polemics such as yours everyone not convinced previously will immediately jump right on with your worldwide program of forced austerity and extreme poverty for those living in Third World economies. Surely they'll gladly give up their meager coal supplies in order to jump on the inefficient, costly and fantasy - based green energy schemes that are still in their nascent stages of development. You want to really walk the talk instead of just blowing smoke? Give up your home and your car immediately, stop wasting energy on computer - powered activities, and never, ever, procreate. How about it?

Harrison said...

Stephen, you can thank the satanist, Wernher Von Braun, for the development of NASA: Never A Straight Answer and the pursuing Rocket Technology. Your government is not your friend.

Placeholder said...

Thanks for that post, Stephen Fry. Here I had thought Seattle had lost its sense of humor.

Joanna said...

Looks like we're in for a little fall weather this week. Any upcoming info on the system coming in Weds with rain & wind?

John Marshall said...

Placeholder... I read Stephen's post as humor also, but given this is Seattle, one can never be sure.

Unfortunately, whether humor or a straight-up freakout, it doesn't matter. I fear that Trump's upcoming war on North Korea is going to occupy most of the planet's attention for the next decades. While dealing with the likely millions of fatalities and clouds of nuclear fallout circulating the globe, I suspect that doing anything to reduce global warming will be reduced to a footnote of history.

I for one remember when Pacific and Asian above-ground testing of nukes (US, China, Soviet) used to contaminate crops in the northern US such that we couldn't drink the milk for periods of time. Too much Strontium-90. Imagine the freakout when your local farmer's market produce and grass-fed milk and meat exceeds the safe level of radiation for human consumption.

And that was when the US government's standards were very low. That was during a time when they used to have soldiers and reporters stand directly below high-altitude nuclear anti-aircraft bursts to prove they were perfectly safe. Guess what... they were wrong. Just took a while for the cancer to get them.

Stephen Fry said...

Hi, Thanks for your replies! I see I've dove into choppy waters. In retrospect, I'm replacing the term "war" with "technological revolution". I feel like patriot Paul Revere, who warned the colonists: "The British are coming!" Yes I like humor, but some things aren't funny - such as devastating hurricanes, out-of-control wildfires and unhealthy air quality. Maybe I'm biased, since I've worked in the environmental and health fields for nearly 40 years, and loved our wilderness areas and national parks since 1960. I can't pretend to be perfect, but I've taken measures to reduce my carbon footprint. The comment about third world countries is a straw man argument. Protecting our planet, through technological advances, will very likely help poor countries - including those people starving in Africa due to ongoing droughts.

wff255 said...

"Build a multitude of large drones to fight wildfires." Ummm, we have done that, we call them "airplanes" and "helicopters". The fact that they are not actually drones and have human pilots do not make them less effective. In general aircraft are ineffective in fighting fire in the conditions seen in California, and any leap in technology is unlikely to change that.

Asher said...

Responsible investment in clean energy is not crazy talk. I know this doesn’t jive with your Trumpian fantasy but we are all grown ups here and stupidity and ignorance should not be tolerated.

Eric Blair said...

"The comment about third world countries is a straw man argument. Protecting our planet, through technological advances, will very likely help poor countries - including those people starving in Africa due to ongoing droughts."

It is not a strawman argument if you don't have any evidence to support your fantasy - based claims. Thorium nuclear technology would have been a life - saving technology if it hadn't been mothballed by the gov't and prevented from further development via lawsuits by the green groups that almost killed it in it's infancy. And yes, of course new technologies could help poorer countries with their many issues - duh. But here's the rub - those technologies aren't there yet, so your solution means they should basically do without any energy whatsover until unicorn farts become viable.

Either offer some timely solutions for Third World nations or admit that you're just moral preening here.

Placeholder said...

So, Stephen Fry wasn't joking after all, but instead doing his best to uphold Seattle's reputation as The City Where Humor Went to Die.

Ansel said...

Frost at my house Saturday morning. I went on a hike near Mt. Rainier. About 10" of snow at 5400 feet. So much for the high country hiking season.

Dan said...

Depends where in the high country you go, Ansel. On Sunday, we drove to the Slate Peak trailhead at 7200 ft. in the North Cascades. We crossed some snow, but we made it even in a sedan.

Slopes on the west side are sure to be snowy soon, but there may be some season left on the east slopes of the Cascades.

tammie said...

Forest fires have occurred naturally for millenia and are actually good for a healthy forest. I know it seems counterintuitive, but we need to let them burn. Fighting them only excaserbates the problem.