December 2014 Observations for the Pacific Northwest

[MikeInEverett]

I'm starting to feel more confident about this, but also cautious to not get too excited. I also think there may still be a chance of snow for me north of Seattle sometime in the late Saturday - Monday period.

[richard mann]

-
.. No model assist, it looks like the cold north of the low at this point, or either cold that moves north of the low, could move more directly south.  @

[TT-SEA]

36 here this morning with no snow at all. Looks like main precip shield is gone now but still some c-zone stuff to the north.

[MossMan]

There were several threads, but here are the main ones. Really fun reads.

 

November 19th-December 8th pre blast speculation thread:

http://theweatherforums.com/archive/index.php?/topic/23503-major-arctic-blast-headed-for-pacific-northwest/

 

December 8th-12th: The immediate buildup

http://theweatherforums.com/archive/index.php?/topic/23786-arctic-outbreak-part-ii/

 

December 12th-16th: The fun begins.

http://theweatherforums.com/archive/index.php?/topic/23898-arctic-outbreak-08/

 

December 16th-19th: Things start to get serious, buildup to the Megastorm.

http://theweatherforums.com/archive/index.php?/topic/23936-cold-and-snow-event-number-2/

 

December 19th-22nd: The Beast.

http://theweatherforums.com/archive/index.php?/topic/24029-epic-megastorm-2008/

 

The easiest way to find the really fun threads is to search by most replies instead of start date.

Thanks!!

 

And it is currently 39 degrees with lumpy rain at times!

[Snow]

[SilverFallsAndrew]

Eugene is now gusting to 32mph from the north.

[SilverFallsAndrew]

33 with wet snow at my house. Having some reports of snow around 1200' near Estacada. Looks like Willamette valley temps are in the upper30s to around 40 right now.

[Snow]

[SilverFallsAndrew]

Temp at Silver Falls State Park went from 50 at 3:15am to 33 by 6:30am.

[Snow]

Eugene is now gusting to 32mph from the north.

Nice, I wish our area would experience North winds more often.

[Gradient Keeper]

12z GFS is underway

Here we go.... Things could still go either way

[Gradient Keeper]

Eugene is now gusting to 32mph from the north.

 

 

Temp at Silver Falls State Park went from 50 at 3:15am to 33 by 6:30am.

To be honest, I don't know which is more impressive. I'll lean towards the Eugene report since Silver Falls is up around 1500' or so.

[TT-SEA]

12z GFS is underway

Here we go.... Things could still go either way

 

 

Feeling pretty good about it now... 12Z NAM is clearly heading towards cold at 84 hours.

[TT-SEA]

33 with wet snow at my house. Having some reports of snow around 1200' near Estacada. Looks like Willamette valley temps are in the upper30s to around 40 right now.

 

 

I think your timing was better... 37 and foggy here now.

[epiceast]

Looks more impressive in Oregon than in Washington.

[SilverFallsAndrew]

The weather station at the park is at 1310'. What it shows is the dynamic isothermal cooling with the front was stronger down here than up in the Puget sound area. I'm not sure if that was because the precip rates were heavier down this way or because the fronts forward movement slowed and it was overswept by a little more cold air aloft.

[SilverFallsAndrew]

This report from Mark's blog....

 

Eugene Dave says:

December 24, 2014 at 6:18 am

Weird. Crazy windstorm occurring right now in Eugene. Easily the strongest winds I’ve observed here at my location this year. A tree that just blew over in my neighbor’s yard woke me up.

[epiceast]

41/41 here and 42/42 in Pasco, I think it's just going to be a degree to warm to be snow at the end.

[TT-SEA]

The weather station at the park is at 1310'. What it shows is the dynamic isothermal cooling with the front was stronger down here than up in the Puget sound area. I'm not sure if that was because the precip rates were heavier down this way or because the fronts forward movement slowed and it was overswept by a little more cold air aloft.

 

 

It was a slow seeping of cold air up here... you could see in the models that the front was going to be energized down there when it swung through.  

[Gradient Keeper]

Awww, dang it!, but I just can't help it I'm such a positive guy..

 

An error occurred

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[epiceast]

This report from Mark's blog....

 

Eugene Dave says:

December 24, 2014 at 6:18 am

Weird. Crazy windstorm occurring right now in Eugene. Easily the strongest winds I’ve observed here at my location this year. A tree that just blew over in my neighbor’s yard woke me up.

http://www.nwac.us/weatherdata/mtsthelens/now/

 

Interesting, the cold air completely missed 50 miles north.

[SilverFallsAndrew]

I'm seeing reports of snow as low as 800' in the N. Oregon Coast Range.

[Snow]

[MR.SNOWMIZER]

I can see snow on gold mountain by my place at about 1200.

[SilverFallsAndrew]

12z looks a little east with the weekend trough, but at least it still shows it.

[TT-SEA]

I can see snow on gold mountain by my place at about 1200.

 

 

The hills are white here as well as the fog breaks up a little so I can see farther.

 

Looks possibly interesting here on Saturday night... will need a c-zone behind the departing system but the cold air is coming in behind it this time.

[Snow]

The new 12z GFS looks good through hour 120, pretty much the same as the 00z/06z earlier.

 

http://www.tropicaltidbits.com/analysis/models/gfs/2014122412/gfs_T850_nwus_21.png

[SilverFallsAndrew]

Salem is down to 39. 0.89" of rain there since midnight.

[SilverFallsAndrew]

I hope the 12z delivers the goods in la la land. lol

[SilverFallsAndrew]

Wow at 6am Eugene reported 30G39 winds from the north. That is almost unheard of for that location.

[SilverFallsAndrew]

Interesting, the temp at my house is the same as at Horse Creek which is 3300' about 7 miles East. Russellville a bit north at 1300' is at 32. So isothermal is the word.

[Gradient Keeper]

12z GFS is exactly like 6z.... no improvements, and not all that impressive at a 850mb stand point. Perhaps 925mb-surface will have deeper low-level cold. Now we watch HR 168-192 to see if the offshore ridge merges/configures with the Aleutian ridge.... hope so, if not.... Yeah.

[Gradient Keeper]

6z GFS 6-10, 8-14 day Analog Composite
Improvement continues. Looks real good long range with sharp retrogression.

 

 

[Snow]

This is why I think the models are too quick to rush out the cold air. Warm air to the right side of the cold air wont verify. The models are confused. Once the cold air gets here, it will be hard to get rid of.

 

http://www.tropicaltidbits.com/analysis/models/gfs/2014122412/gfs_T850_nwus_29.png

[Gradient Keeper]

Nope. No reload on 12z GFS....

[Gradient Keeper]

This is why I think the models are too quick to rush out the cold air. Warm air to the right side of the cold air wont verify. The models are confused. Once the cold air gets here, it will be hard to get rid of.

 

http://www.tropicaltidbits.com/analysis/models/gfs/2014122412/gfs_T850_nwus_29.png

That is real possible to likely.. There should be quite a persistent low-level cold pool which always leads to an extended cold period PDX east.

[SilverFallsAndrew]

This place is dead. 12z must not be that great.

[Snow]

That is real possible to likely.. There should be quite a persistent low-level cold pool which always leads to an extended cold period PDX east.

Yeah I think this is possibly why this run doesn't show a reload. It thinks there's warm air in BC and that stops the flow of the Arctic air heading south.

[Gradient Keeper]

Hmmm, Parallel is very different...

HR 192 sharp shortwave digging south

http://www.tropicaltidbits.com/analysis/models/gfsp/2014122412/gfsp_z500a_namer_33.png

 

Here it is 18 hours later HR 210

 

http://www.tropicaltidbits.com/analysis/models/gfsp/2014122412/gfsp_z500_mslp_namer_36.png

[Gradient Keeper]

Uhhhhh

http://www.tropicaltidbits.com/analysis/models/gfsp/2014122412/gfsp_z500_mslp_namer_39.png