December 2016 Observations and Model Discussion for the Pacific Northwest

[snow_wizard]

I don't think the Fraser valley is going to be ripping next week. Maybe 28/15 type stuff in places like Abbotsford. If the stuff out around day 10 verify, things will be a lot different.

Indeed. It actually appears the most dramatic cold may be during week 2.

[jaya]

I don't think the Fraser valley is going to be ripping next week. Maybe 28/15 type stuff in places like Abbotsford. If the stuff out around day 10 verify, things will be a lot different.

Fraser will be getting a tad windy with the cold.

[jaya]

Indeed. It actually appears the most dramatic cold may be during week 2.

Starting to look that way.  It happened that way in 2008

[snow_wizard]

It's interesting how much the 18z GFS increased precip amounts for the Central Puget Sound this weekend since it switched to showing the low center ending up over south central / SE WA instead of SW WA like previous runs had shown. Seattle seems to do better in backwash situations. The 12z ECMWF also favored a more inland track for the low center.

 

Out smarting the Olympics and down sloping easterly winds is the key for us.

[Perturbed Member]

What is the closest analog to what we are about to experience?  I see several models want to bring low after low starting late next week and dump snow over the whole region. When was the last time we had a good regionwide stretch of cold and snow this way? Most of the recent larger PDX snow events at least have seemed to be overrunning from a low coming out of the SW.

[seattleweatherguy]

Any chance we break record lows? I know coldest low in seattle ever was 0.

[Poulsbo Snowman]

NWS comments leading to this weekend.  Very complex, indeed.

 

.LONG TERM...It is Saturday afternoon and evening where the
  headaches begin. ECMWF and GFS fall out of lockstep for Saturday and
  Sunday...which given the incoming colder air and the precip
  associated with the incoming system...results in a fair number of
  possibilities for the New Years Eve/Day timeframe. ECMWF is more
  progressive and colder with the system...but overall less precip
  while the GFS has more precip...is slower and slightly less cold.
  Given trends in both models...currently more inclined to lean toward
  the GFS solution...which would start the event as rain on New Years
  Eve then changing over to snow during the early morning of New Years
  Day. This sort of timing actually takes the edge off of the greater
  precip amounts of the GFS...placing the bulk of precip more during
  the rain phase...but should rain end up being too much too
  fast...that could actually help the chances for transition to snow
  earlier. If that sounds like hedging or indecisiveness...welcome to
  the fun of trying to forecast snow.  As touched on briefly before
  laying out the scenarios...inclined to lean toward GFS due to its
  more consistent progs. But even with GFS`s own difficulty in guiding
  in regards to transition times...as it seems to be an hour or two
  off using the previous instance as a mental milepost...inclined to
  side with later timings. Definitely too early to suggest
  amounts...but current thinking is to pare back a little bit on
  inherited forecast...bringing lowland snow amounts more in the 1 to
  1.5 inch range. 
  
  Behind all of that hullabaloo...models re-align for cold and dry
  conditions over W WA...with sub-freezing afternoon highs for the
  first half of next week.  SMR 
  
 

[ShawniganLake]

Fraser will be getting a tad windy with the cold.

Indeed, maybe I'm underestimating it a bit, (I hope I am) but it doesn't look like a great Fraser blast early next week. I would wager a fair sum of money its milder than the January 2012 event in the lower Fraser.

[Perturbed Member]

18z NAVGEM continues to keep a lot of precip around Sunday. Looks good especially for SW WA to SEA.

 

http://www.tropicaltidbits.com/analysis/models/navgem/2016122818/navgem_mslp_pcpn_nwus_18.png

[Skagit Weather]

All I'm hoping is that we get a couple inches before I head on back to California for school. Can I order a snowstorm with a side of cold temps on or before Friday the 6th?

[Tyler Mode]

I've recorded more days below freezing this December than the entire winter of 2013-2014...19 so far this month. 18 during December, January and February of that winter.

[snow_wizard]

Any chance we break record lows? I know coldest low in seattle ever was 0.

We might. We haven't had a January record low in ages so it would be cool.

[snow_wizard]

I've recorded more days below freezing this December than the entire winter of 2013-2014...19 so far this month. 18 during December, January and February of that winter.

Are you sure? 2013-14 had two big cold waves.

[BLI snowman]

What is the closest analog to what we are about to experience? I see several models want to bring low after low starting late next week and dump snow over the whole region. When was the last time we had a good regionwide stretch of cold and snow this way? Most of the recent larger PDX snow events at least have seemed to be overrunning from a low coming out of the SW.

December 2008 and November 1985 are probably the two most recent patterns that had as much long-lived deep troughing potential.

[snow_wizard]

What is the closest analog to what we are about to experience?  I see several models want to bring low after low starting late next week and dump snow over the whole region. When was the last time we had a good regionwide stretch of cold and snow this way? Most of the recent larger PDX snow events at least have seemed to be overrunning from a low coming out of the SW.

Looks like 1954, 1957, 1980 are coming up a lot. All had a lot of cold weather and snow. This is old school stuff.

[MikeInEverett]

The bolded posts are back.

[snow_wizard]

18z NAVGEM continues to keep a lot of precip around Sunday. Looks good especially for SW WA to SEA.

 

Much like the 18z GFS. Looks like a good chance the low center ends up either straight south of Seattle or SE of it. Good news for this area.

[HighlandExperience]

Much like the 18z GFS. Looks like a good chance the low center ends up either straight south of Seattle or SE of it. Good news for this area.

Hope it stays that way. We really need snow going into this too make it more enjoyable

[Trainwreck]

You ll threaten some of those if you go into this with some snow cover

We've got about 4-6" in most places right now. There's going to be snow cover with a little on the way that isn't going anywhere.

[Perturbed Member]

Hope it stays that way. We really need snow going into this too make it more enjoyable

 

I think you guy swill do fairly well up there. 

 

Maybe a trace to an inch here at best. Hopefully we can get something going into this.

 

http://www.tropicaltidbits.com/analysis/models/gfs/2016122818/gfs_mslp_pcpn_frzn_nwus_16.png

I love how its snowing in most of OR here, even at the beaches and from OLM to SEA but there is magically no precip over PDX and the north OR coast range. 00z GFS better fix that. 

[crf450ish]

Down to 20 already here with plentiful cloud cover.....hmmmm. 

[Bryant]

Indeed. It actually appears the most dramatic cold may be during week 2.

 

Really wouldn't be surprised to see this pattern persist through most of January, with improvement around mid month. The fact that we have an Aleutian ridge anchored in place while MJO is currently over the western hemisphere is what stands out the most to me. The Nina background coupled with favorable QBO is doing the job nicely, and I don't see any reason why that would change. The WHem forcing is also why we are seeing the SE ridge relax over the next week or 2. Once the MJO propagates back into the eastern hemisphere, especially the east IO/MC region, it will only help to reinforce the pattern in my opinion. Timing won't be exact, but as mentioned previously, I think the MJO moves into the best territory sometime around mid month, which should also pump up the SE ridge once again. Let's make history, preferably with a lot of snow in the picture  

[snow_wizard]

Down to 20 already here with plentiful cloud cover.....hmmmm.

That's warm compared to what you will get next week.

[snow_wizard]

Really wouldn't be surprised to see this pattern persist through most of January, with improvement around mid month. The fact that we have an Aleutian ridge anchored in place while MJO is currently over the western hemisphere is what stands out the most to me. The Nina background coupled with favorable QBO is doing the job nicely, and I don't see any reason why that would change. The WHem forcing is also why we are seeing the SE ridge relax over the next week or 2. Once the MJO propagates back into the eastern hemisphere, especially the east IO/MC region, it will only help to reinforce the pattern in my opinion. Timing won't be exact, but as mentioned previously, I think the MJO moves into the best territory sometime around mid month, which should also pump up the SE ridge once again. Let's make history, preferably with a lot of snow in the picture

Most models show some big time stuff in the 10 to 15 day period. ECMWF ensemble says block is still in place at day 15. That thing is looking epic.

[SilverFallsAndrew]

I'm astonished the record for the 1st is from this year. Really quite unbelievable in fact.

 

For Klamath Falls that is definitely some low hanging fruit for record lows... Their all-time record is in the -20s I believe. 

[SilverFallsAndrew]

We get our cold from the Fraser Valley. Jan 1950 was colder in Seattle than Portland.

 

Maybe for the month as a whole, but Portland's all-time record of -3 was in 1950. Salem's -10 on the 31st was the all-time record until 1972. 

 

1950 was milder as you went south, even Portland was about 3-4 degrees colder for the month than Salem and Eugene, I believe January 1949 and 1930 were colder at SLE. 

[SilverFallsAndrew]

What is the closest analog to what we are about to experience?  I see several models want to bring low after low starting late next week and dump snow over the whole region. When was the last time we had a good regionwide stretch of cold and snow this way? Most of the recent larger PDX snow events at least have seemed to be overrunning from a low coming out of the SW.

 

Right now I give a best case scenario as something like January 1957, the potential is there. That was a pretty great month, but a notch down from January 1930,50, or 69 type madness...

[Timmy Supercell]

For Klamath Falls that is definitely some low hanging fruit for record lows... Their all-time record is in the -20s I believe. 

 

I see -25 on 01/23/1962 but not 100% sure if that's the all-time.

 

But yeah anything below -10 is top tier cold for here. There are only about 8-10 lows recorded between -15 and -25.

[kokaneekidz]

What is the closest analog to what we are about to experience?  I see several models want to bring low after low starting late next week and dump snow over the whole region. When was the last time we had a good regionwide stretch of cold and snow this way? Most of the recent larger PDX snow events at least have seemed to be overrunning from a low coming out of the SW.

It was Christmas time 1996 I believe, snowed off and on for abouta week with temps in the mid 20's mostly. I pulled my friends around on innertubes behind my honda civic. Oh the good ol' days. Then it all melted around new years and the carports and marinas collapsed with all the weight of a foot of snow with lots of rain soaked into it. WOuld like to see a natural sublimation melt in the sun over a 2 week stretch versus the havoc of a pineapple express following one of these events.

[snow_wizard]

Just a quick list of great Januaries....ones that featured at least half the month being very cold and in most cases snowy.

 

1854

1862

1868

1875

1888

1890

1893 (was only cold late, but possibly the coldest air mass to strike this area in the 1850 to present period)

1907

1909

1916

1929

1930

1937

1943

1949

1950

1957

1963

1969

 

They just kind of stopped there although 1980 came kind of close.

[BLI snowman]

Just a quick list of great Januaries....ones that featured at least half the month being very cold and in most cases snowy.

 

1854

1862

1868

1875

1888

1890

1893 (was only cold late, but possibly the coldest air mass to strike this area in the 1850 to present period)

1907

1909

1916

1929

1930

1937

1943

1949

1950

1957

1963

1969

 

They just kind of stopped there although 1980 came kind of close.

1979 was certainly top tier for cold for outflow areas.

 

Great month in general here. It had at least some snow on the ground the entire way through.

[BLI snowman]

NAM looks different, quicker and drier. But it really sucks with CAA, especially at 84 hours, which may as well be 384.

[SilverFallsAndrew]

We've got about 4-6" in most places right now. There's going to be snow cover with a little on the way that isn't going anywhere.

 

Yeah I could see at least -20 then.

[crf450ish]

That's warm compared to what you will get next week.

I know. I just want my D**n negative numbers for low temps. If I have to drive to Sherman pass or Republic to get my -20F fix, I will. I want my kids to see hot water turn to snow  . 

[crf450ish]

Just a quick list of great Januaries....ones that featured at least half the month being very cold and in most cases snowy.

 

1854

1862

1868

1875

1888

1890

1893 (was only cold late, but possibly the coldest air mass to strike this area in the 1850 to present period)

1907

1909

1916

1929

1930

1937

1943

1949

1950

1957

1963

1969

 

They just kind of stopped there although 1980 came kind of close.

Got any details on 1893 temps?

[SilverFallsAndrew]

I see -25 on 01/23/1962 but not 100% sure if that's the all-time.

 

But yeah anything below -10 is top tier cold for here. There are only about 8-10 lows recorded between -15 and -25.

 

Yeah the -25 is the all-time record. The -20 you had in 2013 is the December record. Records only go back to 1959 at the airport, I bet the older station has an all-time record in the -30 range. 

[SilverFallsAndrew]

It was Christmas time 1996 I believe, snowed off and on for abouta week with temps in the mid 20's mostly. I pulled my friends around on innertubes behind my honda civic. Oh the good ol' days. Then it all melted around new years and the carports and marinas collapsed with all the weight of a foot of snow with lots of rain soaked into it. WOuld like to see a natural sublimation melt in the sun over a 2 week stretch versus the havoc of a pineapple express following one of these events.

 

Down here in W. Oregon we had heavy rain and highs in the 50s. 

[MR.SNOWMIZER]

I just drove 18 miles to find cell service to check the forum lol. Sickness.

[snow_wizard]

1979 was certainly top tier for cold for outflow areas.

 

Great month in general here. It had at least some snow on the ground the entire way through.

I thought about that one. It was a pretty lame month for the Seattle area though.

 

Kind of interesting you could also add 1911 for Whatcom County. Very disproportionately cold up there that month.

[Deweydog]

I wish January started tomorrow!!!!!!