luterra

How the heck did it get cold enough to snow in Roseburg? There is no cold air to the north, east, or south, and no advection to speak of. Nor are dewpoints low enough for evaporative cooling. Must be cooling from above under heavy precip, a la 3-21-2012.

When did Portland last hit 50? Last time here in Corvallis was on 2/2.

That's over the next 8 days, though it's still about 3.5" from the AR event. We would have flooding concerns if that verified, but it probably won't. The GFS doesn't have a good enough terrain model to account for valley rain shadowing accurately.

Somehow our coldest air mass of the season only gave me a low of 28 in Corvallis this morning, definite bust on the 18-20 predicted. Too much cloudcover and mixing. South winds kicked in at 10 am, headed for rain. Latest GFS shows the atmospheric river pushed north to our area for Mon-Tues, gives me 5" at face value in the next 8 days. That much water with relatively low snow levels will definitely help with the drought at least :-).

Meteostar is goofed up today; trying to get a good local output from the 18z. The region is not going to shut down, for long anyway. It only takes some filtered February sunshine at 30 degrees to melt off the main roads and runways, and highs are still at or above freezing for the western lowlands throughout these events. Sun is finally out here in Corvallis, making a run at 40 degrees but don't think it will make it.

I'll be at Breitenbush Hot Springs (2300', east of Detroit, OR) next Mon-Wed for a conference of sorts. Assuming I can get there the Euro says I might see 3-4 FEET of snow. Sounds fun!

Hi-res models showed the most wind on the east side of the Willamette Valley, and that seems to have held true. Peak gust of 18 so far at my house in Corvallis, 32 at the airport. I've seen higher on many a summer afternoon.

Eugene temp up to 53 with the wind. Still 42 and calm in Corvallis. SLP slowly rising since bottoming out at ~987 mb just before 6 pm. Right on schedule.

29.14" in Corvallis, lowest pressure since January 2017. Strange quiet day, would never guess there is a windstorm coming if not for the models.

Portland NWS busted on flood potential here in Corvallis, where we are up to 1.77" rain for the day and still dumping, our local Marys River is approaching major flood stage. I guess it's time for the folks up north to get their snow while we get the fate of northern California this time around. Pressure bottoming out here now around 990 mb.

Tail end of the heavy stuff passed me around 10 pm, over Salem now, probably will clear Portland 12-12:30 at this rate. I would not be surprised if everything after that is pretty anticlimactic. With the low inland and starting to fill, the main low-level moisture tap should be cut off. 1.31" of rain in Corvallis today - that is at least double any model or NWS QPF.

700mb low over Astoria, surface low over Coos Bay. PDX is in the southeast quadrant of the upper level circulation - right under the moisture train - and in the northeast quadrant of the surface circulation which turns the gorge tap on full bore. Perfect setup... Starting to wonder about my flight tomorrow morning, though I'm betting they'll at least get the freeways and runways plowed as it lightens up, and maybe all this white stuff will scare enough Portlanders off the roads that it won't be gridlock.

Low has moved inland, lowest pressures now over Roseburg and Eugene. http://www.tropicaltidbits.com/analysis/models/hrrr/2017011102/hrrr_mslp_wind_nwus_5.png

Corvallis is up to 0.9" of rain today and 3" total liquid equivalent since Saturday (including snow and ice). Raining hard at present. Low is elongating up the valley, surface winds are southerly on the east slopes/cascades and northeasterly on the west slopes/coast, dead calm here in the center. http://www.tropicaltidbits.com/analysis/models/hrrr/2017011101/hrrr_mslp_wind_nwus_1.png

Some area SLPs: North Bend (OR) 29.30", up from 29.29" an hour ago Newport 29.35" Corvallis, Eugene, Roseburg all 29.36" Salem, Redmond 29.38" Portland 29.45" The Dalles 29.65" Not much for gradients away from the gorge.

I'm flying out tomorrow 10:55 am, hoping for the best. Probably equal chances that the shuttle gets stuck in traffic until the flight leaves, or the flight is cancelled... 995 mb (29.38") in Corvallis now, still falling, low coming onshore around Coos Bay 992-993 mb. North winds down the valley but 5 mph or less and gradients will be lessening as the low moves overhead. Not much in the way of cold air advection here. 700 mb closed low/circulation center seems to be taking shape over far NW corner of Oregon, as modeled and now evident in radar circulation. If 4km NAM/HRRR are correct that feature will remain stationary through tomorrow morning.

NWS is tired of overhyping storms; they know that there is potential here but still too many variables to pin down exact amounts. The hi-res models have no real down-valley gradient with this system. With cloud cover, southerly 850 mb flow, and light surface winds I wouldn't be surprised to see just cold rain away from the gorge. Not much for an east side cold pool at present either, and models show Bend and southward staying fairly warm through tonight.

Umpqua/Toketee is probably my favorite hot spring in Oregon, though it is frequently abused. Best visited via skis or snowshoes in the winter when the road is closed.

The GFS has been spitting out some goofy low temps lately. 00Z gives PDX a low of 5F on Friday morning with -2C at 850mb and -1C at 925. Inversion overestimation?

Day visits are $18-$32, sliding scale. Lunch is $13 but their meals are quite good. Reservations are required with a limit of 20 per day - weekends tend to fill up a month in advance. When I was single I used to go to Cougar Hot Springs east of Eugene - sometimes nice, sometimes full of partiers. With my wife or visiting friends I'm willing to pay more for Breitenbush which is always a peaceful experience.

Spent the day at Breitenbush Hot Springs at 2300 ft, 10 miles east of Detroit, OR. Snow usually melts at that elevation between storm events. Right now they have 24-30" snow depth and counting, with ice glaze still on the trees. Beautiful, though trees are starting to get overloaded and cause roadblocks. Back at home in Corvallis temp is bouncing between 37 and 39, rising when convective showers bring some wind to the surface. Snowcover has been slow to melt here in Corvallis, will probably go completely tomorrow.

I suspect it has to do with the very warm 850 mb temps coupled with easterly 850 mb flow which is downsloping and merging/mixing with cold easterly gorge outflow. The GFS seems to have a pretty good handle on this. http://wxweb.meteostar.com/sample/sample.shtml?text=kpdx Question will be what happens when upper flow turns southwesterly with gorge winds continuing, though steady at 33 might be more likely than a return to ZR.

This happened in December as well - despite logic and predictions to the contrary, Eugene was the last to switch to rain and the biggest ice winner (loser?). I would assume it is part of the same phenomenon that makes the south valley the last place to clear in an inversion pattern. Without enough of a push to mix the atmosphere, slow moderation leaves cold pockets in the most sheltered locations. Also missed by the models and mets: 850 mb flow is southeasterly at present (southwest is more typical), which is eroding the cold air faster on the west side of the valley while leaving cold pockets all along the east side from Eugene up through Sweet Home.

Above freezing in Corvallis as of 8:30 am. Looks like we picked up about 1/10" of ice overnight. May the slush begin...

00Z Euro brings the midweek low through Tuesday afternoon, never really reloads the Columbia basin cold pool, then sends warm air up to 60º latitude by hour 240. Uncertainty is the rule...