December 2015 in the Pacific Northwest

[TT-SEA]

It's been quite a while.  I remember one in the 90s sometime.

 

 

I guess there was one in January of 1990.    Has it really been a quarter of century since we had a low of this strength and track??

[Gradient Keeper]

High Wind Watch upgraded to High Wind Warning for PDX/Willamette Valley... NWS must be very confident. Decent chance it fizzles now.

[MR.SNOWMIZER]

It's been quite a while.  I remember one in the 90s sometime.  Come to think of it that one was probably further north because the Everett area had damaging NW winds on the back side.

there were two in feb 94 or 95 in a row that dumped 30 inches of snow at sea level on canal. I remember a raging east wind over here.

[Gradient Keeper]

I guess there was one in January of 1990.    Has it really been a quarter of century since we had a low of this strength and track??

And November 3rd 1958...

[TT-SEA]

Rob... the HRRR comes out every hour and there is tons of great data.   Get busy!!

 

http://rapidrefresh.noaa.gov/HRRR/Welcome.cgi?dsKey=hrrr_jet&domain=t1&run_time=20+Dec+2015+-+19Z

 

 

Here is the new HRRR for 11 a.m. tomorrow... way south!

 

http://rapidrefresh.noaa.gov/HRRR/for_web/hrrr_jet/2015122019/t1/wind_t110m_f24.png

[MR.SNOWMIZER]

What was strength of November 2010?

[Gradient Keeper]

And November 3rd 1958...

I posted all of the information regarding the January 1990 and November 1958 wind storm. I'm glad no one checked it out. lol

http://theweatherforums.com/index.php/topic/1120-december-2015-in-the-pacific-northwest/?p=99362

[snow_wizard]

Fabulous GFS run.  Perfect track, great precip intensity, and colder than previous runs.  850s down to -4 over SEA by late afternoon.  Those numbers are good enough for snow.  Still the bothersome chance it could track north of what is being shown, but this run is stellar.

[Deweydog]

This one is kind of unusual.  Normally this type of low happens with SW flow aloft whereas this one is more of straight W flow.  Going to be an interesting event at any rate.

 

I wouldn't call it unusual, just not a typical high wind setup.  Kind of reminds me of 11-22-2009, just with a slightly stronger low, potentially.  Gradients were primarily westerly with that event as well.  The bent back occlusion brought some wicked westerlies to the north end of the Long Beach Peninsula.  

[snow_wizard]

What was strength of November 2010?

 

That was way different.  Much colder air in play.

[TT-SEA]

Fabulous GFS run.  Perfect track, great precip intensity, and colder than previous runs.  850s down to -4 over SEA by late afternoon.  Those numbers are good enough for snow.  Still the bothersome chance it could track north of what is being shown, but this run is stellar.

 

Sweet!  

 

Data coming in faster than I can keep up.  

[Deweydog]

I guess there was one in January of 1990.    Has it really been a quarter of century since we had a low of this strength and track??

 

There's been many.  January 1990 just happened to hit a pretty narrow corridor allowing a HWW to verify at PDX.  

[TT-SEA]

There's been many.  January 1990 just happened to hit a pretty narrow corridor allowing a HWW to verify at PDX.  

 

 

That is what I thought... it can't be that unusual.

 

Rob... waiting for analysis on the HRRR.     You should be in data heaven!

[MR.SNOWMIZER]

That is what I thought... it can't be that unusual.

 

Rob... waiting for analysis on the HRRR.     You should be in data heaven!

the big question is how many produced snow in lowlands.

[BLI snowman]

NWS certainly a little quick to jump on the High Wind Warning gun but I understand that the saturated ground will make it easy for 50mph gusts to bring down trees. Not really impressed with the chances that we'll see anything more.

[Gradient Keeper]

18z GFS HR 84

 

http://www.tropicaltidbits.com/analysis/models/gfs/2015122018/gfs_z500_mslp_namer_15.png

[Gradient Keeper]

HR 96 ridge just as sharp as 12z
 

http://www.tropicaltidbits.com/analysis/models/gfs/2015122018/gfs_z500_mslp_namer_17.png

[SilverFallsAndrew]

Gfs a little cooler this run.

[Timmy]

Just home and surprised to see a rain snow mix at 40f

[MossMan]

the big question is how many produced snow in lowlands.

That is my question as well...

[Deweydog]

Little Christmas Day drive up to the Larch might be in order!

[Deweydog]

the big question is how many produced snow in lowlands.

 

12-16-92 and 1-18-96 both did.  Those two had quite a bit more of a residual cold air mass/wet bulb assistance to play with however.  

[Gradient Keeper]

We do not need a Wind Storm, especially with Christmas nearing. People don't need to deal with the hassle of power outages, perhaps for day or 2, or tree damage and what not.... First time in forever I'm not rooting for a Wind Storm.......

[MikeInEverett]

The usually wrong weather.com has 2-4 inches of snow for me from Wednesday night into Thursday.

[Deweydog]

We do not need a Wind Storm, especially with Christmas nearing. People don't need to deal with the hassle of power outages, perhaps for day or 2, or tree damage and what not.... First time in forever I'm not rooting for a Wind Storm.......

 

I'd be pretty surprised if anything 50 or better verifies tomorrow at any of the metro reporting stations.  Justin's right though, the squishy landscape will probably magnify what will be a pretty marginal event at worst. History tells us these west/east systems rarely are able to realize themselves to the surface like a more adiabatic system would. The 1-8-90 system is a poor analog in my opinion just for that reason. That system was much warmer and hence had a much easier time mixing the stronger gusts to the surface.  

[FroYoBro]

Here are the more detailed maps of the new 18z NAM-4km for tomorrow. Strong winds at the surface as the low deepens and races through Washington. I think hurricane force wind gusts are very possible.

 

 

Oh please. This map doesn't show winds even close to hurricane force. 

[Front Ranger]

12-16-92 and 1-18-96 both did.  Those two had quite a bit more of a residual cold air mass/wet bulb assistance to play with however.  

 

If the Nov 2003 setup could produce lowland snow, I think this setup is more than capable. The air mass in place isn't cold, but it's chilly.

[Deweydog]

If the Nov 2003 setup could produce lowland snow, I think this setup is more than capable. The air mass in place isn't cold, but it's chilly.

Bringing up November 2003 is like comparing apples to Tony Siragusa.

[MR.SNOWMIZER]

Sometimes the nws blows my mind. Not even any hint of snow or a mix for the hood canal forecast. Wow... Most of the huge snow events here were not forecasted anyway.

[SilverFallsAndrew]

Long range gfs really sucks

[MossMan]

Sometimes the nws blows my mind. Not even any hint of snow or a mix for the hood canal forecast. Wow... Most of the huge snow events here were not forecasted anyway.

They are probably waiting until tonight to introduce snow into the forecast since the placement of the low is critical.

[luvssnow_spokane]

Long range gfs really sucks

Things have to balance out eventually.

[MR.SNOWMIZER]

I guess there has not been much improvement in forcasting in ten years. Most of the models are showing or hinting at snow around hood canal and other places yet not even in the forecast? so are they just ignoring the data? Even if it were not showing up on the mm5 the pattern still deserves a mention of snow in the forecast when we are 24hrs away.

[snow_wizard]

The 18z based snowfall maps are even better than the 12z for the Central Puget Sound region.

 

Image credit WeatherBell

[Front Ranger]

Bringing up November 2003 is like comparing apples to Tony Siragusa.

 

You're missing the point. It wasn't that this setup is similar to Nov 2003.

[crf450ish]

I guess there has not been much improvement in forcasting in ten years. Most of the models are showing or hinting at snow around hood canal and other places yet not even in the forecast? so are they just ignoring the data? Even if it were not showing up on the mm5 the pattern still deserves a mention of snow in the forecast when we are 24hrs away.

I feel the same way most of the time. Haven't lived in my current location long enough to have a valid opinion on the forecasting. So far, it seems better then that of western wa forecasts. I know the farther east you move, the easier forecasting is.... For me, living on the west side pretty much was a guaranteed fact that it was going to rain (or drizzle) nearly non stop from the beginning of November till about the end of May, beginning of June.... with a few sun breaks in between. I know, sounds weenie-ish, but thats how much I hate the rain. Yeah yeah, rain is a necessity, but after eons of outdoor plans being ruined because of it Ive about had my fill of it for the rest of my life. 

[MossMan]

I guess there has not been much improvement in forcasting in ten years. Most of the models are showing or hinting at snow around hood canal and other places yet not even in the forecast? so are they just ignoring the data? Even if it were not showing up on the mm5 the pattern still deserves a mention of snow in the forecast when we are 24hrs away.

This is a portion of Seattles latest AFD...

OVERALL THIS SNOWFALL IS TOO UNCERTAIN TO MENTION IN THE FORECASTS.

 

And in fact they did not want to get specific on anything this week.

[Timmy]

The 18z based snowfall maps are even better than the 12z for the Central Puget Sound region.

 

Image credit WeatherBell

Oregon?

[Bryant]

18Z NAM track is absolutely perfect.

 

Too bad its the worst run of the worst model.

Perfect is relative

[snow_wizard]

Pretty interesting graphic on WeatherBell comparing the accuracy of the ECMWF and GFS.  The GFS is getting close.