Yuck! Check out this X-Section from the UW WRF-GFS. Time goes from right to left…from this evening to Monday evening.
The green areas indicated a saturated atmosphere (generally fog or cloud cover). Note that from later tonight to at least Monday evening the airmass overhead is saturated from the surface to 10,000′? That says November gloom ahead. Get out the anti-SAD lamps folks! It’s a warm front coming through tomorrow with the freezing level jumping well above 10,000′.
Okay, let’s talk about that previous post. Wasn’t that a fun forecasting exercise? It’s tough to actually write down a forecast, then have to stick with it through various model runs…I see a few of you even tweaked it a bit after the 00z GFS came out. My only mistake is that we should have done it 24 hours ago when long range models were colder.
Here’s my forecast:
THURSDAY: 40/45 Light rain
FRIDAY: 35/45 Showers (that low is probably too low, but that’s on the 7 Day.
SATURDAY: 35/43 Turning partly cloudy, a shower?
The GFS is a bit warmer than this…it would be in the mid-upper 40s Saturday.
So there were rumors floating around MediaLand this afternoon of a possible arctic blast or snow to sea level coming up next week. It’s pretty obvious that it isn’t cold enough for either through at least 8 days from now (next Saturday/Sunday). The new 00z ECMWF just came in and is almost exactly like the 12z run. We just turn cool and dry later Saturday and Sunday. The 00z GFS was similar, except notably warmer.
To sum it up…as of now I still don’t see a decent chance for lowland snow or an arctic blast in the next 7-10 days. But definitely colder with some good mountain snow. With northerly flow forecast in the ECMWF (not GFS now), we have to keep a close eye on things though.
Chief Meteorologist Mark Nelsen
FOX 12 Weather Blog 
KPTV should have a forcast on the website or something where the bloggers come up with there own. I think that would be kind of cool :).
You can always use my website Forecaster: http://www.northwestwx.com/forecaster
It’s still in the early stages, and thus is a work in progress, but it’s functional and it spits out forecasts that look similar to Mark’s 😛
Thanks man, ill look at that right now 🙂
Since it’s not finished, feel free to give me any comments or suggestions!
No snow flake in the forecast? Dang.
Mark? What about that beer?
Mark, you’re flirting with the danger zone, showing that big purple trough dropping out of the North… 😆
Saw your photo, too Antipex! The graphics intern mis-spelled your first name, tho. 😳
Great…that would be me.
Heh… oh well. At least you can fix it for the next time if it’s shown again. 😀
*Shakes fist* Damn interns, I mean, Mark! 😛
hey you can’t blame me now
It’s only 48 degrees outside the house here but feels at least 10 degrees colder with the rain and damp weather.
LOWER COLUMBIA-WILLAPA HILLS-I-5 CORRIDOR IN COWLITZ COUNTY-
INCLUDING THE CITIES OF…ST. HELENS…CLATSKANIE…CATHLAMET…
WILLAPA…FRANCES…ELK MOUNTAIN…LONGVIEW…KELSO…CASTLE ROCK
238 PM PST SAT NOV 13 2010
.THURSDAY NIGHT…MOSTLY CLOUDY WITH A CHANCE OF SHOWERS. SNOW LEVEL 2000 FEET. LOWS 35 TO 40.
.FRIDAY…MOSTLY CLOUDY WITH A CHANCE OF SHOWERS. SNOW LEVEL 2000 FEET. HIGHS 45 TO 50.
.FRIDAY NIGHT…MOSTLY CLOUDY WITH A CHANCE OF SHOWERS. SNOW LEVEL 1500 FEET. LOWS 35 TO 40.
.SATURDAY…MOSTLY CLOUDY WITH A CHANCE OF SHOWERS. SNOW LEVEL 1000 FEET. HIGHS 45 TO 50.
So if I get busy and get the studs on, all chances of snow are off. But….if I’m not prepared it will probably snow….hmmmm….what to do!!!
There seems to be an awful lot of water coming out of the sky for the radar being so blank…
It’s like very heavy mist!
A lot of it is being generated out of the lower clouds today, so the radar beam is shooting right over the top.
Yup, just saw you on the Telly saying that very thing, Mark. 😉
Hehe I haven’t heard someone say “telly” since I was in Australia!
Don’t know why I chose that word… just came out at random.
I would not be surprised at all if 00z shows -15 850 temps over PDX..
Nice to see our first real chance of the cold stuff ( freezing temps/snow) could be coming before Thanksgiving! I foresee many changes to forecasts very soon.
Get ready for the 7 days to change by tonight’s telecasts.
I’ll check it once I get back home tonight. First I’m watching the Ducks game then heading out to see A Perfect Circle at the Showbox here in Seattle.
It seems like momentum is building for a cold snap of some type. Modified? just through the Gorge? or a true arctic blast such as 18z suggests. We need 1-2 more days. I will say do not be surprised if some future model runs are absurdly cold.
If the 500mb pattern shapes up this way it is very possible we see something as the 18z advertises, or even colder.
Or revert back to milder. Hopefully this projected pattern turns out right!
salivation time
models continue snow flirt
batten down hatches
Very nice haiku
Snow is falling in the words
Are the models good?
Fewwww….. Meteostar didnt refresh when I looked at Troutdale. So I thought it was still showing warm since last. Glad!!!! Starting to get real interesting!!! 🙂
The Spokane NWS discussion this afternoon does talk about next weekend some…
FRIDAY INTO THE WEEKEND…THE LONGWAVE PATTERN WILL HAVE SHIFTED FAR ENOUGH SOUTH…PLACING THE JET INTO OREGON…AND THE INLAND NW ON THE POLAR SIDE. THE AFOREMENTIONED NORTHERLY JET ACROSS NW CANADA WILL CONTINUE TO FEED SHORTWAVE ENERGY INTO THE LONGWAVE TROUGH ACTING TO “RELOAD THE GUN” SO TO SPEAK. IT WILL BE ANY ONE OF THESE WAVES WHICH ROUND THE BASE OF THE TROUGH AND EJECT INTO OUR VICINITY WHICH WILL BRING A CHANCE FOR SNOW TO ANY LOCATION. FOR THE MOST PART…SNOW LEVELS WILL BE ALONG MOST VALLEY FLOORS. ADDITIONALLY…THE ARCTIC BOUNDARY WILL ON OUR NORTHERN DOORSTEP AS EARLY AS SATURDAY…POSSIBLY SPILLING INTO THE INLAND NW SUNDAY. THIS IS SUPPORTED BY SOME GUIDANCE BUT HAS NOT BEEN VERY CONSISTENT RUN TO RUN SO CONFIDENCE REGARDING THE ARCTIC AIR INTRUSION AS WELL AS DETAILS WHEN/WHERE SNOW ARRIVES IS LOW. MY HIGHEST CONFIDENCE IS RELATED TO THE PROBABILITY OF BELOW NORMAL TEMPERATURES. /SB
brrrr… 18z run is a cold one. I need to see that kind of air within 180hr mark on the models to believe it’s a real possibility.
Man,shows Spokane, WA with down to 507 thickness and -20c 850mb temps. Brrrr…
http://wxweb.meteostar.com/sample/sample.shtml?text=ksff
The Dalles gets to -14c… our friendly Gorge feeder.
Hey, check out Seattles…
http://wxweb.meteostar.com/sample/sample.shtml?text=KBFI
Hour 240 -3F in Seattle?!? Bahaha!!! I don’t buy that.
OK… At this point, when this upcoming week will become interesting? Yesterday, I heard Friday, the 19th. Now I’m seeing Saturday or Sunday. I have to go to Seattle on Friday, will I see snow, or Ice on or along I-5?
Do you ever notice that posts like this never get responded to?
Yeah.
Yes, I have noticed that. Just wondering if I will need to put on my studs for Friday, or can I do it on Saturday, back home?
I suspect one of the reason why these questions don’t get answered, is because the blog is getting frequent posts, so the questions that was asked, falls to far back from the top.
I think it’s because things are still too uncertain, and no one wants to commit to a definite answer yet. If I knew, I’d say. If I had to make a guess, I’d say rain turning snow showers Friday evening, snow Saturday in Seattle, +24 hours for Portland. BUT, that is purely a speculative, uneducated guess, so take that for what it’s worth.
Doesn’t look like it at the moment … just the usual cold rain
Too early too say.
Similar Analog? Noticed the Nov 1985 pattern on here..
NICE! and 1955!
Can’t hate the 95% correlation either.
I love seeing maps like these. They’re so rare! Usually all the cold air spills into the nation’s midsection, cut off by the Rockies. I know the models often forget to factor in the Gorge, but they couldn’t have ignored the Rockies this time, too. (Could they?)
The reason the cold is spilling onto our side is due to a couple reasons. First the upper atmosphere (500mb) continues to bring the air from up north. On top of that, what we need to get cold air is a low pressure system off the coast, to suck the cold air out toward the pacific. We have both of those things which is why models are forecasting cooler temps.
But you are right, in general the models don’t do stellar with geography.
What an incredible shift over the past 12-18 hours in models. There is decent agreement, but is this the final trend? Is this cold solution locked in? I want to say YES, but I want to see another day or so of runs like this.
YES!!! 😀
Sorry, my enthusiasm got the better of me there…
Come on Mark, can you give us at least one flake on the 7 day? Just to feed our delusions?
18z is an arctic blast for PDX, if not it is as close as you can get to being one.
http://wxweb.meteostar.com/sample/sample.shtml?text=kttd
I think you will all like these! 🙂
18z Sat night into Sunday wants to give us a couple inches of snow.
I got my model riding chaps on for the 00z.
Rob, I really appreciate your analysis and links. Your posts offer information for both the geek and greenhorn (like me). Thanks.
Sarah, you’re welcome and thank you too.
18z is a MUCH better run especially in terms of jet/upper level support you can clearly see this. Also thicknesses/850mb temps and nice southwestward progression of the cold air. If there are any concerns about not being cold enough? The cold will be there…. Models aren’t going to be able to initialize or recognize it yet… In fact if the 500mb pattern and trough digs like this on future runs I think they could easily turn colder…
The 500mb pattern is great, I agree with that. The models want to keep the cold air wrapped up just north of the low. If the low digs a tad further south, or the 00z has a similar 500mb forecast, I also agree lower atmosphere temps will go lower.
The odd thing is that this run and the ECMWF are not too far off in terms of L placement and 500mb pattern, they are different in how cold the air will get though. I expect Mark to stick with the ECMWF though.
If 00z EURO trends like this….
Holy cow lala lands is awesome.
Hour 204 and later is COLD! Get’s us with 850mb temps below -12C!
The tease is BACK ON!!!
So what is gonna go down Saturday? We have heavier moisture with the 18z, temps are slightly warmer though. Right now it looks like cold rain, with snow down to 1000-1500′. The low is feeding off frigid air to the north, but unlike past runs, the real cold air doesn’t drift over the pacific, so it gives the air plenty of time and distance to moderate.
Sunday on the other hand has great upper air dynamics, with cold enough temps and some moisture still to work with. That could be a snow scenario down to 500′ or even lower. The only issue is that it looks like Sunday is what Saturday was, as in, the ol’ GFS pushing back a day?
just pushed a 1 day back, fine with me to be honest I wouldn’t mind since I got school on Monday 😉
Correct me if I am wrong, hours 174-192 show snow here all the way down to the valley…850 temps around -6/-7
The gorge is completely socked in today…
http://www.moonlightr.com/viewArt.php?id=25
Can I use your picture on the evening newscasts?
Awesome pic
I emailed you a couple versions Mark – feel free to use them!
THat low is really teasing us around 160-172…
This is promising
I would say so!
wola!