The IT”S GOING TO GET COLD AND SNOWY IN THE LOWLANDS weather party is over; crashed by models showing we have some normal lower late winter snow levels and just cooler than average temps on the way. More on this below…first today:
This morning a nice cold front has moved south of our area and now quite a bit of clearing showing up from the Metro area north and west visually and on the satellite image as well. Cooler air is moving into the Cascades after yesterday’s abnormally warm day. After a few showers the rest of the day, the weather will be quite slow through Friday morning. Another cold front slides in here Friday afternoon for renewed rainfall.
Now, what everyone really wants to know about for this coming weekend…
1. Sticking snow is very unlikely where 90% of us live, below 1,000′ along the I-5 corridor in the western Valleys. It’s okay if you removed your studs if you live in the lowest elevations. I don’t see any traffic issues the next 5 days at least on area roadways.
2. There is no unusual late season arctic chill on the way. If you turned on water to your outside faucets? They’ll be just fine.
So who will and when?
1. Above 500′ in the Coast Range some sticking snow is possible Saturday afternoon/night and into Sunday morning.
2. Near and above 1,000′ here in the Western Valleys, including the top of the West Hills, Mt. Scott, Sandy etc…most likely a little (less than 2″, or maybe just a trace) Saturday night or Sunday morning.
3. Up around 1,500′ and higher, 2-4″ looks good Saturday afternoon/evening through Sunday midday when it dries out.
The cold trough that swings in late Friday and Saturday bringing lots of showers also produces a strong south-southwest wind during the day Saturday. That coupled with marginal 850mb temps -5 to -7 along with slightly too warm soundings is the reason I don’t think there’s any chance of lowland snow through Saturday evening. 
You can see the strong wind right away Saturday morning on our RPM text output. The surface flow turns light by Sunday morning as slightly colder air moves in (-7 to -8 @ 850mb.), but then the moisture goes way down for just light showers. Check out the 24 hour rainfall forecast between 4am Sunday and 4am Monday off the UW WRF-GFS. 
Only around .10″ in the driest parts of the metro area up to around .50″ in the wettest parts of the Coast Range. One more reason to not get excited about anything other than flurries or light rain/snow showers under partly to mostly cloudy skies Sunday. Plus, it’s the end of February and temps jump each afternoon unless you get steady precipitation and solid cloud cover. It’ll still get up into the 40s.
Another cool trough comes through next Tuesday and Wednesday, but this one will be marginal again for snow in the lower elevations; possibly a good shot in the foothills again. You can see how cool it is through the whole Sunday-Wednesday period on the WRF-GFS cross-section. 
I’ve added a solid blue line to show the 2,500′ elevation and the dotted line is the 32 degree temp. If you want snow in Portland you want to see that line dip extremely close to (or down to) the surface. If there is moisture for showers, the Monday morning dip is plenty chilly, and Sunday morning looks close as well. Otherwise the freezing level is hovering up around 2,000′ most of the period.
Looking farther ahead, here is the 12z GFS ensemble chart and last night’s 00z ECMWF chart. Lots of below average 850mb temps as we head into March, but generally nothing too extremely cold. This could be the best snow of the winter (the next 10 days) if you live up around 1,500′! It appears the mountains are FINALLY going to see their La Nina winter as we head into meteorological spring (March-May).
And one more chart just for fun, the mild winter may morph into a mild spring across the USA; check out the 850mb chart for Chicago. Several periods of well above average temps, in fact most of the time it’s above average:
Chief Meteorologist Mark Nelsen
wow…what’s with all the earthquakes under Mt Hood. Glad they are small….hopefully relieving stress so as not to go…….well you know.
Some decent thunderheads forming here in Pachuca, which is about an hour northeast of Mexico City. I’d include a pic if I knew how. Getting back to Portland 11:30 tomorrow night. Will there be snow in the air?
Accuweather says 2.2 inches of snow on the way!!!:))
InAccuweather?
Now looks like even more moisture.
http://wxweb.meteostar.com/sample/sample.shtml?text=KTDO
That’s like eight inches of snow Saturday/Sunday…..and more on Wednesday!
Nice run! PDX looks like it still could eek out some snow later this weekend. You are looking good up there!
It looks good, but one thing you have to take into account is the way the grid is measured, especially after the resolution change. If I remember correctly, at that resolution the models see the Columbia River valley from Scappoosia, through Longview across to Gifford-Pinchot as universally around 2,000 feet. Troutdale is also seen at around 1,000 or 1,500 feet on the KTTD charts… That’s a considerable margin of error!
As long as scappoosia gets the goods, I’ll take the error!
I think you should change your name to pappoose in scappoosia. Just sayin’ …
Looks a little snowy to me, and below 1000 feet if I’m reading this correctly!!!
http://wxweb.meteostar.com/sample/sample.shtml?text=KTDO
As of noon Salem is partly sunny and 52 degrees. Had a morning low of 31. Tomorrow with some sun and warm south winds we could see lower sixties for highs. Some cooling for the weekend and beyond. Probably mid to high forties for our highs. Snow level should drop to around 1 to1.5k ft, so no snow on valley floor, but Cascades could get hammered. Good news all around.
Sounds like a sure thing above 1000 ft. Anyone else have updates on latest models?
12z gfs and NAM both bring some modest accumulating snow here Saturday nite/ Sunday AM
ECMWF 00z Brings 1-2 inches of snow down to the surface Tuesday Night, west of Hillsboro (Forrest Grove / Cornelius)
I’m kind of thinking Mark may have called this off a bit prematurely
A low of 31 this morning. My 16th freezing low of the month. My minimum for the month is a pretty unimpressive 29.
My temperature has yet to drop below freezing this February. My coldest temperature has been 32.7°F so far this month. Last time my temperature dropped below freezing was on 1/28 when it dropped to 29.7°F
…33.1 with a snow shower this am….
Really fun to get a series of colder storms!
National Weather Service Portland or
224 am PST Thursday Feb 23 2012
A sharp cold
front moves through the region Friday evening…followed by a much
colder air mass Friday night. The cold and unstable air mass will
linger through the weekend. A series of colder storms impacts the
area next week…which will bring plenty of snowfall to the Cascades.
I like (:
If it weren’t for Dad being with me I’d assume I was going crazy.
Please read this before answering my question asking why Silverton road was so unusually busy.
After 8pm Dad and I did an emergency run to get gas at the Central Howell Shell before gas hits $4 dollars a gallon (the prices are rising 10 cents every day and it’s predicted to go to AT LEAST $6 dollars by summer minimum)
We got their after stopping at another store by 9pm just before the gas station closes for the night.
The road was PACKED with traffic though strangely they were NOT going to the gas station which I was worried their was already a gas-panic going on.
Only us and one other car were at the station which is a normal amount that time of night but the roads tell a different tale.
Dad usually gets off from the pharmacy from Portland at 7pm and gets to Silverton road between 8 and 8:30pm which he usually is The Lone Ranger though once in a while he will get one or two other stragglers.
In fact on the way home at the four-way stop there were cars stopping from all directions. I kid you not. I’ve only seen that kind of traffic either at noon or 4pm since I refuse to drive anywhere during rush hour.
The way the traffic was I wasn’t sure if I was imagining it or not.
I’ve only been to Silverton a handful of times. I wouldn’t know what to tell you, Kyle.
I love Silverton, no matter what it will always be home. Traffic can be heavy in the evenings on Silverton Rd as many people in Silverton communte to and from Salem for work.
2/22/2012 Oregon (All) Temperature Summary
Warmest:
High:60 at Rye Valley(I-84(2230 ft) & CW2426 Warmsprin(1572 ft) & LAKE OWHEE AND O(2400 ft) & DW7237 Pendleton(1145 ft) & CW2710 Maupin(1040 ft) & CW2426 Warmsprin(1572 ft) & LAKE OWHEE AND O(2400 ft) & DW7237 Pendleton(1145 ft) & CW2710 Maupin(1040 ft)
Low: 49 at Rufus 2E(279 ft)
Coldest:
High:33 at Timberline Lodge(7001 ft)
Low: 16 at CW7477 Lostine (7002 ft ) & MT. HOWARD (7910 ft )
Largest Diurnal Change: 31 degrees
CW8689 Burns (57/26 ) (4219 ft )
Heaviest Rainfall:
2.58″ at LOG CREEK(2800ft)
2.43″ at CEDAR(2220ft)
2.26″ at HEBOWX Mt. Hebo(3160ft)
In Mexico City thru Friday. Had some good thunderstorms last night. Temps around 75 and partly cloudy. I could get use to this.
I’m going there not long from now. Sounds fantastic!
Ended up with .7″ of rain up here today. Over 6″ on the month now so back near average. High today was 45, the current temp of 36 is the low so far.
Jupiter and Venus are out together on a planetary date tonight!
http://oi44.tinypic.com/1087pd5.jpg
Don’t they make a cute couple?! ^_^
If you’re concerned about the awkward distance between them, don’t worry. They’re working it out, and they’ll be getting closer over the next few weeks. The Moon will try to come between them toward the end of this month, but won’t quite be successful. The two will dance on March 14th before going their separate ways…
There is nothing wrong with being realistic as long as one remains open the possibility of surprise events since Mother Nature will do what she wills and since we are in a new climate regime springs will most likely be very funky from here on out.
Right now I am just happy the mountains are going to get dumped on and the skiers will have some late season powder to play on.
In E body else happy about mountain snow which is the most important thing of all?
Doesn’t take much accumulation to make me a happy camper! Don’ you just love the most extreme of cases!
National Weather Service Portland or
220 PM PST Wednesday Feb 22 2012
Long term…as the extended period begins Saturday evening…
showers taper off behind saturdays front. The upper level pattern
has the Pacific northwest in cool northwesterly flow with the mean
ridge near 145w. The Pacific northwest sits just ahead of the next
shortwave embedded in the flow that is due to affect the area on
Sunday and Monday. As the shortwave digs south the models begin to
differ slightly on the strength of the incoming trough but in the
most extreme of cases drops the snow level to near the valley floor
on Monday morning. The cooler air arrives with precipitation of a
showery nature…making it more likely for scattered rain and snow
showers with not much accumulation in lowland areas.
You’re just like me! Haha. Gotta hold on to that hope!
Hahaah!
Temperature dropping like a rock here under this shower, down to 40 degrees.
Make that 38.
Time to stop complaining about no low level snow and cold. Let’s do something about it! According to ‘the butterfly affect’ (chaos theory), the flapping of a butterfly’s wings in Mexico can affect the weather in the US. Make a point to go outside the next few days, face W or SW and blow hard several times. Maybe a weather blog CAN change things. But, if you feel like passing out…stop blowing. I can’t wait to see what Mark has to say on Monday.
I’m in!
Seems like we got plenty of “blow hards” here already. That’s probably what’s screwin’ up the winter
Like this? http://youtu.be/vdFIXsrjkXI
I prefer the old-fashioned method: twirl a magical staff in front of you and utter arcane incantations over and over again, evoking the weather deities and requesting sea-level snow accumulations this weekend. Works every time!
Karl
Bring those incantations to the snow party. We really need all the help we can get.
0.14″ <<< 1.00"
Much less rainfall than expected today!
0.14″ since midnight.
0.21″ last 24 hours.
0.49″ here
Well we can still wishcast on the second temperature dip expected for the middle of next week. Maybe we at least get some hilltop snow out of that one….
I’m also worried that since this is essentially an early spring cold spell, it could be accompanied by some very nasty cold west winds in the Gorge. A 40-mph gust when it’s 42 degrees outside is NO FUN AT ALL.
18z shows a massive winter storm in 2 weeks but what else is new…
That should stay out at the 10-14 day range until about the end of March. After that, it’ll turn into a death ridge.
Looking forward to the Death Ridge!
Give me July 2009 but hotter, that’s my kinda death ridge!
Nothing wrong with being realistic at all. I think most of us would liked to have had an epic winter. I know I would have liked to have had at least one cold and snowy outbreak. But it just isn’t very likely to have that once you get into early March. So now we can all complain about the lack of warm weather. I don’t think this spring will be as bad as the last two but who knows. In any case winter is most surely over.
A shower is passing now and my temp is down to 45.5 and just had a wind gust to 29 mph, my strongest of the year.
Wow! Wunderground says I get Snow Tonight!! LOL
Sunny here now but there is a nice band of heavy dark clouds up to the north.
I actually got some yard work done today!
You know, without sounding like a jack@$$, I’ve repeated nearly these exact same words several times over the last few days with regard to this coming weekend over on both FB groups, and was baited for a response yesterday — to which I AGAIN said nearly these exact same words — and yet I keep getting referred to (whether directly or on the side, which is irrelevant) as a Negative Nancy, Debbie Downer, pessimist, what have you. I guess I’ll just never understand why taking a realistic stance gets one labeled such derogatory things? Facts are facts, and wishcasting one’s way to premature forecasm does not a legitimate forecast make! And just because I choose NOT to ignore a handful of important variables — like the fact that it’s LATE FEBRUARY! — doesn’t make me into a pessimistic drag.
In fact, here’s what I said yesterday that drew a fair amount of criticism, quoted directly:
Now, how does this line up with what you’ve said in this post, Mark?
Let’s break it down…
====================================
Wind Direction
Mark: The cold trough that swings in late Friday and Saturday bringing lots of showers also produces a strong south-southwest wind during the day Saturday.
Me: …showers that do approach from our W-SW…
====================================
Snow Level
Mark: 1. Sticking snow is very unlikely where 90% of us live, below 1,000′ along the I-5 corridor in the western Valleys.
Me: Areas with any elevation should get snow, sticking above 500 to 1000 feet, but below that in the cities we should only expect a mix…
====================================
Precipitation
Mark: Only around .10″ in the driest parts of the metro area up to around .50″ in the wettest parts of the Coast Range.
Me: The Coastal mountains will be hard at work gobbling up any showers that do approach from our W-SW, however anything that does manage to cross into the Valley will fall as a mix at best.
=====================================
I hate to b!tch, but the labels are really getting old.
So Mark, welcome to the Pacific Northwestern Society of Pessimistic Meteorological Forecasters! Which one do you want to be, Nancy or Debbie? I’m indifferent.
In my opinion, I think most of us just don’t want to hear it. We probably accept that there is going to be snow, but with such a low snowfall winter as this and our basic weather history we want to hope for that incredible snowfall.Thus causing our rational reasoning skills (when it pertains to weather to go down the drain). In the grand scheme of things, I wouldn’t take the words too personal.
Careful W7. Your traipsing awefully close to the “I’m a victim / stop labeling me” cliff that a former not-to-be-named long-time poster fell off of. Thicken that skin up.
Yeah, I know, I’m sorry. It’s just ridiculous. I vented, and without an exorbitant amount of profanity! I’m all better now.
I still want desperately to be wrong in my assessment of this pattern though…
I really enjoy this blog–particularly for the special insight provided in Mark’s posts–but these kinds of comments are a drag, especially since the complaint is about labels made on a “FB group.” Who cares? With that said, I really appreciate the detailed, frequent updates as of late, Mark. Great blog!
But I DO agree that you shouldn’t be criticized for being a realist. Now for the frequency with which you quote yourself . . . maybe. The term “self-importance” comes to mind.
Only when it serves to prove a point.
Erik,
Two things, the 2nd is probably the main problem
.
1. I think people just get annoyed if comments are almost always negative.
2. People don’t want to hear bad news and they get really worked up if you tell them that several times.
Yes Mark, I understand both of these things. However, “negative” is all a matter of perspective. It could be said by many that taking a “No, it’s not going to snow next weekend.” stance is being positive, and the “OMG, we’re going to get 3 inches of snow next weekend!” stance is negative. While pretty to look at and fun to play in, snow is quite dangerous, and for those that drive for a living it can be a serious hindrance or even a detriment to their jobs, or their very lives. If one becomes all excited at the prospect for snow covered roadways in the presence of a commercial truck driver for instance, they might be liable to get slapped upside the head a time or two.
Granted, it’s all about your audience, and here on your weather page (where most everyone is about equally as crazy about weather extremes as I am), pro-snow is the way to go! By the same token, I think wishing for snow leading up to marginal events is a ridiculous waste of internet space. To me, it surmounts to wishing for 100 degree heat in September. [hyperbole] It could happen if conditions lined up a little better, but it’s not gonna happen this weekend. [/hyperbole]
Realism might be annoying to some, but I find it equally annoying when the models hint at the possibility of a marginal snow event and some certain individuals latch on full-bore and start screaming for the next Snowtastrophe. Really?? They should know better. How many times can one cry “WOLF!” before people just stop paying attention? Three kicks to the nuts last winter was more than enough for me… I turned it off a long while ago.
What I’d want to see before I’m sold on real snow in PDX:
● 850mb temps –9 or colder.
● Sub-520dm heights.
● 0 Southerly component to winds at the surface.
● Dewpoint below freezing.
● Precipitation.
● Inside FCST HR 60.
● SP on vacation out of the area, or otherwise distracted.
● Matching 5 of 6 on Powerball.
● The Voice of Mark to utter the word “snow” on-air.
I’m ready for some sunny 70s.
Can’t help it Mark. I always get excited about flurries or light snow showers!
The party’s over??? I didn’t realize it’d actually gotten started…
Hahaha!! I wasn’t going to name names…
….i’ll be keeping my hatches battened down, it looks like!…
Snow party at Larry’s
…as a matter of fact, i was kinda thinking of bbqing a turkey behind the store while i’m working this weekend.. !
Thanks for the update Mark. Looks like small hail could occur during the next week at times with that cool air aloft.