November 2015 in the Pacific Northwest

[Dave]

No 4pm obs. That's too bad. I was curious where the highs ended up.

This page has the 4pm obs.  Doesn't have tigard though:

http://www.nws.noaa.gov/view/prodsByState.php?state=OR&prodtype=hourly

[snow_wizard]

Looks like the GFS has led the way for the first half of December.  The ECMWF has and it's ensemble look pretty decent in the 8 to 10 day period.  The ensemble shows full blown cool zonal flow at day 10.  We're still in business.

 

Thanks to a very chilly finish SEA will end up over 1.5 degrees below normal for November.  I'm pretty shocked they scored a low of 25 out of this cold snap.  Dropped to 21 here last night.

[snow_wizard]

Oh baby!

 

[crf450ish]

For my neck of the woods: 

 

 

 

 

.DISCUSSION...

 

Tonight through Tuesday...A pair of weak upper level disturbances

pass over the ridge of high pressure over the area but do little

other than to force a bit more snow flurries out of the stratus

and add a bit more cloud cover for the mountains and elevations

above 4000 feet MSL which are poking above the low stratus clouds

which remain entrenched over the valleys and lowlands below 4000

feet MS. Having more flurries occurrence usually means that the

fog will remain less prevalent and ceilings will rise a little bit

and there will be a very slight warming trend in daytime high

temperatures for Tuesday relative to those of today. /Pelatti

 

...light to moderate snows possible over portions of the Inland

Northwest as well as areas of freezing rain between Tuesday night

and Thursday...

 

.Tuesday night through Thursday...Confidence is quite high that the

stable ridge which has sat over the Inland NW for the past week

or so will begin to break down or shift into western Montana. This

will result in an increasing threat of precipitation as the mid

level flow pattern turns increasingly southwesterly and brings

Pacific moisture into the region. The first threat of

precipitation arrives early in the evening at the Cascade Crest

and moves steadily eastward into Wednesday morning. This feature

is fairly progressive and expected to weaken into the ridge over

Montana. Consequently the chances for the heaviest precipitation

will likely occur over northern and western portions of the

forecast area, including the Cascades. Precipitation amounts won`t

be all that heavy with the heaviest amounts expected to occur over

Chelan, Okanogan and Douglas counties, where anywhere from

0.10-0.20 inches of liquid is expected. Initially the

precipitation will fall as all snow, however a slug of above

freezing air is expected to slowly wedge its way into the southern

portions of the Columbia Basin and perhaps the Wenatchee area by

Wednesday morning. This could bring some light freezing rain to

locations such as Moses Lake, Ritzville, and Vantage as the warm

wedge rides over the sub-freezing air near the ground. This would

likely impact much of I-90 across this area so travel problems are

certainly possible. Farther north all the precipitation will fall

as snow with 1 to 3 inches possible over the northern valleys with

an less than inch over the vast majority of the region. Overall

this is a fairly minor system but the threat of ice could produce

moderate impacts.

 

The bigger problem with the forecast is the second system which

is expected to move in from the southwest in the form of a warm

front on Wednesday. This system is expected to pack much more

moisture and potentially more problems. The 12z GFS and 12z NAM

brought the warm front into the lower Basin, and Wenatchee area

before sunset and push it slowly north toward the Canadian border

by Thursday morning. Meanwhile the ECMWF and Canadian models hold

off any threat of significant precipitation until Thursday

morning. This is a big difference to say the least and would have

large impacts on the area weather. If the GFS and NAM solutions

were correct, we`d be looking at moderate precipitation amounts

with the sub-freezing air holding stubbornly near the ground.

There is the other question as to how long would this sub-freezing

air remain near the ground as the winds aloft increase steadily.

Near the Cascades we expect the freezing air to remain the longest

and deepest as there is a good offshore pressure gradient which

will reinforce the cold-air damming. Moderate snow amounts would

be possible especially over Okanogan, Chelan, and Douglas

counties. The warm wedge of air aloft would also transition the

snow to freezing rain especially for the Columbia Basin, Wenatchee

area, Waterville Plateau, and Okanogan Valley. The warm air aloft

could also move into the northern Washington and Idaho Valleys

late Wednesday night resulting in a smaller risk of snow changing

to freezing rain. Farther east and south the transition from snow

to rain would be more steady, so for places like Spokane, Pullman

and Ritzville we`d be looking at snow amounts less than an inch

with more liquid than snow. Of course this is assuming the NAM and

GFS solutions are correct. That is a BIG if at this point.

 

The ECMWF, Canadian, and new 18z GFS hint at a much slower arrival

of the warm front with little if any precipitation until early

Thursday morning, We would still see the possibility of some mixed

winter precipitation ahead of the warm front including in the

Spokane area but the switch would occur fairly quick. All models

concur that 850 mb temps and consequently snow levels skyrocket as

the front comes in so significant snows won`t be the problem if

the latter solutions verify. By Thursday afternoon, 850 mb temps

soar to well above zero for all locations except near the

Cascades, so rain would become the primary precipitation type.

Needless to say the confidence for this forecast is quite low. We

will hold off on winter highlights for now and focus our efforts

via social media and weather stories. fx

 

 

 

 

They emphasize their lack of confidence in this forecast discussion...

[crf450ish]

Oh baby!

 

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/ECMF_phase_51m_full.gif

I dont even have the slightest clue what I'm looking at, other then the U.S. is situated middle top of this diagram?

[stuffradio]

I dont even have the slightest clue what I'm looking at, other then the U.S. is situated middle top of this diagram?

Phases 2 and 3 = cold for the PNW.

[Jesse]

Seasons be damned!!!

Seasons and anomalies have no bearing on one another, despite what "Dewey's law of ideal weather" may dictate (torching 95% of the year and maybe a little cold in December or January just for shits and giggles).

[Jesse]

What did we ever do before the internets...

Was on my phone between work and class.

 

#thestruggleisreal

[snow_wizard]

Phases 2 and 3 = cold for the PNW.

 

Actually 4 and 5 are the most likely to bring Arctic air.  At least from what I've seen over the years.  The forecast shows a wave in 4 a bit later in December.  I think the ball will be in our court around Christmas time.  Hopefully we can do something with it.

[Deweydog]

Seasons and anomalies have no bearing on one another, despite what "Dewey's law of ideal weather" may dictate (torching 95% of the year and maybe a little cold in December or January just for shits and giggles).

 

You really have no idea.  Good thing you're in school!

[Front Ranger]

I think he's cranky that the extended period of warm anomalies is ending, if anything.

 

That post you quoted got deleted. Apparently we're not allowed to call someone "anti-fuzzy" around here. Or explain that you're not actually calling someone a "frozen turd". That post got deleted too - ironically, I made it to make sure the mods understood I wasn't name-calling.  <_>

 

Seriously? Mods, I know you've come under some criticism lately and I think you do a tough job well overall (used to be in your shoes), but there's been a few headscratchers lately.

[stuffradio]

Actually 4 and 5 are the most likely to bring Arctic air.  At least from what I've seen over the years.  The forecast shows a wave in 4 a bit later in December.  I think the ball will be in our court around Christmas time.  Hopefully we can do something with it.

I've seen charts showing phase 2 and 3 giving the PNW below normal temps, although according to this, we want phases 1 or 2 or 7 though. http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/mjoupdate.pdf

[Front Ranger]

Departures

 

PDX -12

SLE -14

EUG -15

 

Solidly below normal November in the books. Coldest since 2007 for EUG.

[Front Ranger]

I think the pattern will turn very wet again soon for the PNW. This is the Euro ensemble height mean for days 6-10...pattern screams above normal precip for the west coast.

 

 

[Jesse]

You really have no idea. Good thing you're in school!

Good thing. Math and science are way more interesting than professional ambulance chasing anyway!

[TT-SEA]

Looks like the GFS has led the way for the first half of December.  The ECMWF has and it's ensemble look pretty decent in the 8 to 10 day period.  The ensemble shows full blown cool zonal flow at day 10.  We're still in business.

 

Thanks to a very chilly finish SEA will end up over 1.5 degrees below normal for November.  I'm pretty shocked they scored a low of 25 out of this cold snap.  Dropped to 21 here last night.

 

 

Way too early to say which model is leading.    

 

00Z GFS just followed the the ECMWF for Wednesday and Thursday.   How can you say what will happen in the long range with certainty?    Never works for me.  

[TT-SEA]

I think the pattern will turn very wet again soon for the PNW. This is the Euro ensemble height mean for days 6-10...pattern screams above normal precip for the west coast.

 

get_orig_img.png

 

 

Hope it comes with tons of mountain snow!  

[Front Ranger]

Actually 4 and 5 are the most likely to bring Arctic air.  At least from what I've seen over the years.  The forecast shows a wave in 4 a bit later in December.  I think the ball will be in our court around Christmas time.  Hopefully we can do something with it.

 

[Deweydog]

Good thing. Math and science are way more interesting than professional ambulance chasing anyway!

Except when it comes to the math of determining daily temperature anomalies, of course. NWS officials might need an ambulance if they don't change that up soon, yo!

[Jesse]

That post you quoted got deleted. Apparently we're not allowed to call someone "anti-fuzzy" around here. Or explain that you're not actually calling someone a "frozen turd". That post got deleted too - ironically, I made it to make sure the mods understood I wasn't name-calling.

 

Seriously? Mods, I know you've come under some criticism lately and I think you do a tough job well overall (used to be in your shoes), but there's been a few headscratchers lately.

That does seem like a strange choice of deletions.

[Front Ranger]

Hope it comes with tons of mountain snow!  

 

At this point it looks that way towards the end of the period, but too soon to say.

[Front Ranger]

That does seem like a strange choice of deletions.

 

Perhaps whoever deleted them was in a rush and didn't read carefully. Or was having a bad day. Or just thought it would be fun to throw darts and delete posts.

 

I'm not upset. Just baffled. 

 

For those who follow sports, I view moderating like officiating: it's not so much how strict you are, but how consistent. Of course, refs/umps have the benefit of solely focusing on the game at hand; I know it's hard to follow everything that goes on here closely, especially if you have a life.

[Deweydog]

Perhaps whoever deleted them was in a rush and didn't read carefully. Or was having a bad day. Or just thought it would be fun to throw darts and delete posts.

 

I'm not upset. Just baffled.

 

For those who follow sports, I view moderating like officiating: it's not so much how strict you are, but how consistent. Of course, refs/umps have the benefit of solely focusing on the game at hand; I know it's hard to follow everything that goes on here closely, especially if you have a life.

And that's it for tonight's installment of Life Lessons with Jared. Stay tuned after the news for Dr. Laura.

[Front Ranger]

And that's it for tonight's installment of Life Lessons with Jared. Stay tuned after the news for Dr. Laura.

 

Fringe stuff, man.

[Front Ranger]

0z GFS goes nuclear with GOA low. 951 mb at hour 180. Granted, this is the far reaches of GFS accuracy. Still fun to see.

[Deweydog]

Fringe stuff, man.

Not quite as out there as dry-advection-aiding-and-abeting-the-formation-of-a-strong-inversion-pattern kind of stuff, but it's still out there. Weird life lessons.

[Deweydog]

0z GFS goes nuclear with GOA low. 951 mb at hour 180. Granted, this is the far reaches of GFS accuracy. Still fun to see.

A couple runs recently had it down around 940.

[Front Ranger]

A couple runs recently had it down around 940.

 

Well , Dewey, you've one-upped me again! Was it within 180 hrs, though??

[Deweydog]

Well s**t, Dewey, you've one-upped me again! Was it within 180 hrs, though??

Totally! Probably lost your focus amongst all that nitpicking over zonal flow. Happens to the best of us.

[Front Ranger]

Totally! Probably lost your focus amongst all that nitpicking over zonal flow. Happens to the best of us.

 

I rarely look at the GFS past hour 168. You know that.

[Deweydog]

I rarely look at the GFS past hour 168. You know that.

Snob.

 

But sorry, it was in the 5-7 day range. Sokay, though.

[bainbridgekid]

If this is right the Nino is about to fall off a cliff.

 

[SilverFallsAndrew]

I am most interested in hour 312.

[Deweydog]

I am most interested in hour 312.

Don't waste your time. He won't look.

[Front Ranger]

If this is right the Nino is about to fall off a cliff.

 

 

 

All signs point to that. The chances of heading straight into mod/strong Nina territory (ala 1998) are mixed. Sometimes it happened after really strong Ninos, but there are many times it hasn't: 1958, 1966, 1983, 1992 all went neutralish.

 

I'd say about 50/50 we go full blown Nina.

[SilverFallsAndrew]

I am most interested in hour 312.

 

Oh cold onshore flow!

[Phil]

Haha, 00z GFS is so strong w/ the GOA low that it pushes the downstream surf zone and subsequent wave breaker into the NAO domain, sending the lower PV column (100-30mb) into Siberia.

 

That'd certainly be a bizzare way to initiate winter. Either way, it'd be transient as the PV reconsolidates fairly quickly.

[SilverFallsAndrew]

The 00z says there will be arctic air in the lower 48 in December!

 

http://mag.ncep.noaa.gov/data/gfs/00/gfs_namer_384_1000_500_thick.gif

[Front Ranger]

Right now the trend in the models is to amass the coldest air in the NH in Siberia, leaving most of our side of the globe quite warm. I will feel better about the chances of cold air down the road (probably after Christmas) if we see Alaska turn cold again towards mid December.

 

One thing we definitely don't want to see is a really warm December in Alaska. Historically, that's led to nothing good for the PNW during Ninos. Take a look at the list of +ENSO years with +7 or warmer December anomalies at Fairbanks. It's a who's-who of non frozen turd fests.

 

2014

2002

1993

1986

1982

1969

1963

1947

1939

[luvssnow_spokane]

Pretty!     Me like color... Me think nice...  *grunt*