December 2015 in the Pacific Northwest

[snow_wizard]

Was there ever an event that was similar as far as duration and overall setup in recorded history? Late 1800's? Wasn't there some epicness around 1917? I really would want nothing more than to experience a 1950 type event. My grandparents were so lucky!!

 

1861-62.  That winter was colder and cold for a longer time than 1949-50.  The conditions at Fort Vancouver were so bitter it could easily rival a respectable New England winter.

[Phil]

Interesting to see Jan 1985 is a top analog right for the pattern progged at days 8 and 11 in spite of that being a La Nina. Another one that catches my is December 1976...another one where we went directly from an overhead ridge to an Arctic intrusion a bit later on.

 

There are a number of odd things going with this Nino such as the current MJO wave making a strong showing regions 4 and 5 and an SOI average for the last 4 days +19.65. An SOI like that with this ENSO should be impossible, but it is happening. We have a shot at the warmest anomalies remaining over the NC and NE parts of the country in January after those areas receive some relief from the warmth early in the month. All just speculation right now though.

Yeah, January is definitely a transition month as we've talked about (mid-Jan NAM flip/SSW), but should still turn out warm over most of the northern half of the country.

 

That said, I'm expecting a more classic Niño/+PNA/-NAM from late January into February, so after another shot of nationwide warmth mid-month, the eastern half of the nation will probably see the brunt of winter after January 25th or so.

[Jesse]

Mostly with the late month event. The Columbia Basin cold pool was off the charts at the end of January 1950. This sh*t was pretty stupidly ridiculous

 

http://www.wunderground.com/history/airport/KDLS/1950/1/31/DailyHistory.html

That probably helped the legendary sub-zero temps at PDX along a bit.

 

Stupid fake cold!

[snow_wizard]

Mostly with the late month event. The Columbia Basin cold pool was off the charts at the end of January 1950. This sh*t was pretty stupidly ridiculous

 

http://www.wunderground.com/history/airport/KDLS/1950/1/31/DailyHistory.html

 

Below zero with fog.  That is something you rarely see in the NW.

[Bryant]

Trying to help... he does this to himself.

No you're just an a**

[BLI snowman]

Was there ever an event that was similar as far as duration and overall setup in recorded history? Late 1800's? Wasn't there some epicness around 1917? I really would want nothing more than to experience a 1950 type event. My grandparents were so lucky!!

 

1915-16 is probably the closest match to 1949-50 as far as the 20th century is concerned. Those and 1968-69 were probably the three sexiest extended upper level cold periods for us in the 20th century. 

[Phil]

Jan 1950 and Jan 1909 were a couple of cases where extreme -PNA was enough to do the job. Very rare though.

 

An interesting fact about Jan 1969 is minus PNA in combination with very low NAO is what delivered the goods that month. If the PNA is minus low AO or low NAO can be our friend big time.

Yeah, without EPO help, you guys usually need either a strong west-based -NAO or a very amplified -PNA ridge. The latter is almost impossible to do without a Niña/+QBO under declining solar.

[snow_wizard]

Even the high resolution is not backing off on snow. Currently 35 degrees here with no wind .

 

I'm betting you get snow as jealous as I am of that.

[snow_wizard]

Yeah, without EPO help, you guys usually need either a strong west-based -NAO or a very amplified -PNA ridge. The latter is almost impossible to do without a Niña/+QBO under declining solar.

 

We may have a shot at that in the next year or two.

[Deweydog]

Who knows...

 

But yeah, 1950 probably isn't the best example. That is one of the most freakish anomalies in our period of modern record as far as sustained cold in the upper levels goes. Still, I'm sure "fake" cold helped pad the anomalies to some small degree.

Fake cold, or at least subsidence inversions, is far more relevant than CAA itself. Probably 75/25 for the Columbia Basin/gorge/Willamette Valley combo. Strong advection events are pretty rare, mainly mitigated by onshore flow below 900mb and then mitigated by terrain with continental air masses. I would wager our local system is about as low-level dependant as any in the lower 48.

[Jesse]

Fake cold, or at least subsidence inversions, is far more relevant that CAA itself. Probably 75/25 for the Columbia Basin/gorge/Willamette Valley combo. Strong advection events are pretty rare, mainly mitigated by onshore flow below 900mb and then mitigated by terrain with continental air masses. I would wager our local system is about as low-level dependant as any in the lower 48.

Yes, very well said.

 

That's why it kind of mystifies me why it gets such a bad rap here. It is a key aspect of our winter climate and our accrual of wintertime cold anoms.

[MR.SNOWMIZER]

I'm betting you get snow as jealous as I am of that.

dont be. Many times I was jelous of the conversion zone you get when it slides se with a arctic front.

[Phil]

We may have a shot at that in the next year or two.

Watch out in 2017-18, assuming it's a La Niña winter. Would be an early-biased +QBO under declining solar and a relatively strong BDC. Would be the first of it's kind since the 1950s.

[snow_wizard]

Fake cold, or at least subsidence inversions, is far more relevant that CAA itself. Probably 75/25 for the Columbia Basin/gorge/Willamette Valley combo. Strong advection events are pretty rare, mainly mitigated by onshore flow below 900mb and then mitigated by terrain with continental air masses. I would wager our local system is about as low-level dependant as any in the lower 48.

 

Your knowledge always impresses me. 

 

I have kind of thought your final statement is probably true from time to time.  We are good at doing "home grown" cold here.

[MR.SNOWMIZER]

Acually got to zero in a couple places I the okanogan highlands last night.

[snow_wizard]

Watch out in 2017-18, assuming it's a La Niña winter. Would be an early-biased +QBO under declining solar and a relatively strong BDC. Would be the first of it's kind since the 1950s.

 

I hope it works out for us!

[snow_wizard]

dont be. Many times I was jelous of the conversion zone you get when it slides se with a arctic front.

 

That is one time the Puget Sound area often does pretty well.  The winter of 2013-14 was so disappointing because it didn't happen with either cold wave.

[BLI snowman]

Yes, very well said.

 

That's why it kind of mystifies me why it gets such a bad rap here.

 

Obviously fake cold doesn't help us much at face value when it never decouples and 850mb temps are +5c for weeks at a time. Some level of upper level cold air advection is virtually a must for us to get snow.

 

But maintaining low level cold pools is extremely critical to us bettering our midwinter averages. Offshore flow, low level cold, and respectable upper level parameters are all it takes sometimes for us to score a memorable winter. This is probably more true for Portland than for Seattle or Vancouver.

 

January 1960 is a month that never, ever gets discussed on here but followed those guidelines nicely and wound up being one of the snowier months in the last few decades for Portland. No huge upper level support all month long, it was simply a case of us avoiding strong onshore flow while maintaining a healthy inversion for several weeks. 

[Jesse]

Your knowledge always impresses me.

 

I have kind of thought your final statement is probably true from time to time. We are good at doing "home grown" cold here.

We have a very unique combo of latitude and terrain, as well as generally being "upstream" for our continent's main source of upper level cold.

[bainbridgekid]

Anybody else watching WSU in the Sun Bowl?

 

It's in El Paso right on the Mexican Border and they are under a Winter Storm Warning for 3-7" of snow.   

 

Not sure whether to laugh, cry, or scream.  

[IbrChris]

Major "fake" cold episode (upper level ridge) looks to be in the cards as we get into early January...potentially a week-plus of sub-40 highs at PDX with lows in the low to mid 20s. Moisture looks to be pretty much absent however as a strong ridge remains over western Canada through the 11-15 day period. Sharp inversions will be the rule in the valleys both west and east of the Cascades with periods of east winds at PDX.

Today's consensus forecast for PDX combined with 12z model output shows a mean temp anomaly of -2.7 F in the 1-5 day period, -5.6 F in the 6-10 day period and -3.3 F in the 11-15 day period. If some moisture manages to break through underneath the ridge there's a decent risk of wintry precip even west of the Cascades (best chance southern areas of OR and into CA).

 

The CMC while showing a similar 500 mb pattern to the GFS and Euro has much colder surface temps (several days with low 30s/20 at PDX). Looks overdone to me on surface temps and I prefer a GFS/Euro ensemble blend with coldest days mid 30s/mid 20s around Jan 2nd to 5th. This pattern should result in an extended stretch of highs in the upper teens and 20s in the Columbia Basin with the higher Cascades being considerably warmer, potentially into the 40s at the resorts.

[snow_wizard]

Anybody else watching WSU in the Sun Bowl?

 

It's in El Paso right on the Mexican Border and they are under a Winter Storm Warning for 3-7" of snow.   

 

Not sure whether to laugh, cry, or scream.  

 

Ultra deep trough to say the least.

[IbrChris]

Ultra deep trough to say the least.

Feb 2011 was a pretty amazingly deep trough. El Paso got down to -2 I believe.

[SilverFallsAndrew]

Looking at the latest RPM it is showing around an inch possible here with tomorrow's systems. Interesting it is showing nothing for the coast range. 

 

And then I see why...Very sparse precip north of Salem on this model...

 

http://www.cascadeaccess.com/~mnelsen/RPM_RAIN_NWOREGON.jpg

[SilverFallsAndrew]

Hit 34 here today. Down to 33 currently with filtered sun shine. 

[bainbridgekid]

Turn on CBS if you want to see some snow. Absolutely dumping at the Sun Bowl now.

[Gradient Keeper]

DP down to 31 at PDX.

 

29 at TTD.

Dewpoint 28 here. East wind increasing. 925mb cold pool -6c over Columbia Basin. Best cold air locked in north of Hermiston. It should be pretty cold over there and overnight that will transport westward. It'll be close if PDX sees some snow. It really don't take much or need to long of a period of cold east winds to do the job in late December.

[SilverFallsAndrew]

18z looks more like the Canadian to me. 

[SilverFallsAndrew]

Dewpoint 28 here. East wind increasing. 925mb cold pool -6c over Columbia Basin. Best cold air locked in north of Hermiston. It should be pretty cold over there and overnight that will transport westward. It'll be close if PDX sees some snow. It really don't take much or need to long of a period of cold east winds to do the job in late December.

 

Currently 40 in Pendleton

[BLI snowman]

18z looks more like the Canadian to me. 

 

Yup. A little more encouraging for the midweek system.

[Gradient Keeper]

Currently 40 in Pendleton

Yeah. The cold pool has definitely been roughly Hermiston northward... it'll expand though.

[crf450ish]

Watch out in 2017-18, assuming it's a La Niña winter. Would be an early-biased +QBO under declining solar and a relatively strong BDC. Would be the first of it's kind since the 1950s.

I've been watching this lately and I am 120% confident that our sun is on the cusp of a very inactive period. I dug up my old popular science and popular mechanics magazines I've been keeping (since I was a kid) and even back in the mid 90's, there were articles, periodically, that spoke of solar activity and its relation to earth.

 

Back then, I didn't know what I know now about the relation between the sun and the weather on earth. Several of todays top astrophysicists (theoretical physicists) have touched on the relation between the weather on our sun and what happens in space outside of our solar system. Not everything that happens with the sun comes down to fission and fusion of atoms. Just like our Earth is greatly affected by the weather of the sun, the sun is greatly affected by other phenomenon out in space such as quasars emitting X-rays, black holes sucking matter from millions of miles away, and gravity....I could keep going on, but its irrelevant to this forum. At any rate, its all theoretical, and as Phil mentioned in an earlier post, there is no way to model this type of stuff, therefore its fairly unpopular and rather off the political radar (it doesn't make them any money, thats why...). 

 

 

 

 

 

 

As the sun gets older, it grows in size and gets cooler............

[GHweatherChris]

Anybody else watching WSU in the Sun Bowl?

 

It's in El Paso right on the Mexican Border and they are under a Winter Storm Warning for 3-7" of snow.

 

Not sure whether to laugh, cry, or scream.

Of course I'm watching my Cougs. My wife walked in and was like WTF Texas snow, we can't even get more than a rain/snow mix. I love her.

[Timmy]

18z looks more like the Canadian to me.

 

Is that good or bad?

[Deweydog]

Dewpoint 28 here. East wind increasing. 925mb cold pool -6c over Columbia Basin. Best cold air locked in north of Hermiston. It should be pretty cold over there and overnight that will transport westward. It'll be close if PDX sees some snow. It really don't take much or need to long of a period of cold east winds to do the job in late December.

I don't think the cold pool is all that relevant, if at all, for tomorrow's event. Tomorrow is just about a cool residual air mass, little or no mixing, some modest wet bulb assistance and a decent column with what is a fairly cool system. I've been reliving 12-21-97 today.

[Gradient Keeper]

Is that good or bad?

Good.

[hotncold]

El Paso is over 3,700 ft. They get under 10 inches of precip a year with about 7 inches of it being snow, which is more than most lowland locations on the I-5 corridor in the PNW. Amarillo averages about 18 inches of snow per year.

[bainbridgekid]

I don't think the cold pool is all that relevant, if at all, for tomorrow's event. Tomorrow I just about a cool residual air mass, little or no mixing, some modest wet bulb assistance and a decent column with what is a fairly cool system. I've been reliving 12-21-97 today.

Seems like it could be a situation where the outflow prone areas actually mix out and are slightly too warm, but the cold air damming spots wet bulb to snow.

[Deweydog]

Seems like it could be a situation where the outflow prone areas actually mix out and are slightly too warm, but the cold air damming spots wet bulb to snow.

Bingo.

[TT-SEA]

I don't think the cold pool is all that relevant, if at all, for tomorrow's event. Tomorrow is just about a cool residual air mass, little or no mixing, some modest wet bulb assistance and a decent column with what is a fairly cool system. I've been reliving 12-21-97 today.

 

Good information.