February 2019 Weather in the Pacific Northwest - Part 1

[Esquimalt]

Ensembles will be telling

[Andrew.]

 

I'm thinking maybe an inch or so at my place, which I would be more than happy with for this first wave. Just seeing the ground white would satisfy me for now.

 

Looks like they are going for 2" or so here. Which would make sense.

[SilverFallsAndrew]

Just noticed the CFS develops a monster GOA vortex toward the end of the month. Would probably turn things really wet.

[MossMan]

February 2019.

By the end of this month we will all be laughing about how upset we were about the 3rd-5th timeframe. Going to be an epic month!

[BLI snowman]

FV3 looks pretty decent for NW OR and SW WA on Monday.

[TT-SEA]

Just noticed the CFS develops a monster GOA vortex toward the end of the month. Would probably turn things really wet.

That is usually how we come out of these cold periods.

 

Maybe that will set the stage for summer starting in April.

[TT-SEA]

By the end of this month we will all be laughing about how upset we were about the 3rd-5th timeframe. Going to be an epic month!

I actually think this is 100% correct.

[SilverFallsAndrew]

That is usually how we come out of these cold periods.

 

Maybe that will set the stage for summer starting in April.

 

It also develops a huge ridge over most of the continental US. It's actually not far from a March 2012 pattern.

[GHweatherChris]

Hoquiam had 38 of 44 days come in below average from December 4-January 16th. The first 16 days of January 2017 were below average... I really really doubt we'll run a streak better than that in the next month and a half.

 

Olympia and Seattle had 18 straight below normal days from December 30-January 16th.

Very little snow, that's what matters.

[Deweydog]

It also develops a huge ridge over most of the continental US. It's actually not far from a March 2012 pattern.

You had a lot of snow that month!

 

Or so I heard.

[SilverFallsAndrew]

Very little snow, that's what matters.

 

Snowmizer said the longest cool/cold stretch since 2008. That was what I was responding to. My post had nothing to do with snow.

[SilverFallsAndrew]

FV-3 undercuts the block by the 10th.

[TT-SEA]

FV-3 undercuts the block by the 10th.

 

I was thinking that could be the eventual outcome of the majestic pattern that the ECMWF is showing now.    I looked at the last 4 or 5 runs and the trend has been to stretch out the trough farther to the west.   Right now that puts us in the absolute sweet spot.   But a realistic possibility with that pattern is similar to what the FV3 is showing where the trough just gets stretched out too far to the west and the result is a warmer and wetter pattern for the PNW.

 

The factor arguing against that happening is the consistency of the EPS.  

[Perturbed Member]

Other than the OP GFS, most models showing something in the 1-2 inch range for the PDX area on Monday. 

 

 

[Perturbed Member]

Solid discussion from PDX NWS

 

Later Sat night, and especially on Sunday, will see another upper low
pull out of British Columbia and drop south along the Pac NW coast.
This low will tug moisture back across the area, with increasing
showers. Snow levels will gradually lower, but will stay at 1500 to
2500 feet, highest over Oregon Cascades. All models show some low
sitting along or just off the Oregon coast later Sun night, and then
dumb-belling the low back to the west-northwest on Mon. All do show a
frontal boundary arcing northward from Astoria back to the Oregon
Cascades. But, details still fuzzy, as decent amount of model
inconsistency in the movement of the low, which will have direct
impacts on the potential lowland snow.

NAM is the most aggressive, showing lot more in way of offshore flow
through the Columbia Gorge. GFS not so much, with a bit slower trend.
But, it is now starting to follow a NAM trajectory, and keeps the low
a but closer to shore before sending the low back to the WNW on Mon
am. This would favor tad more offshore flow than earlier model runs,
and thus similar trend to that of NAM. Now, the ECMWF seems be
playing the "in between models" role, and is not all that helpful.
So, will trend more towards NAM at this point.

This trend will go with showers Sun night into Mon, with snow levels
gradually lowering to surface for the interior after 1 or 2 am Mon,
and down to sea level to 500 feet along the coast. Seems the primary
band of precipitation will be with the arcing frontal boundary, which
will nearly stall for a time Mon am over far southwest Washington
into extreme northwest Oregon. This will likely be the jackpot for
low elevation snowfall, with 2 to 3 inches possible between
Vader/Castle Rock and Woodland/Scappoose area. Bit to the south, snow
potential for 0.5 to 2.0 inches for Portland/Vancouver metro, with
heaviest to the north and west. Farther south, generally less than an
inch for Willamette Valley. But, could see local spots where may get
an inch or two on higher hills. Coast Range generally 3 to 6 inches
of snow, and same for the Cascades. But, little if any snow expected
to accumulate along the coast under 500 feet.

Now for the big caveat: Unfortunately, this is not a classic snow
situation, where get cold east winds and moisture at the same time.
Rather, it is showery in nature, with cooling temperatures aloft.
Accumulations will be spotty in nature for most areas. All will
depend on where the showers set up, and how long they persist over an
area. As we progress into the weekend, confidence should increase,
and model volatility will settle down, with better idea of what snow
can be expected, where, and when. But for now, those with travel
plans should be prepared for potential of snow covered roads late Sun
night through Mon. Again, alot forecasts are likely to change, so
stay tuned for the latest. Rockey.

[HighlandExperience]

Aberdeen is going to be the big winner

[SilverFallsAndrew]

FV-3 is pretty good late next week. Then gets VERY close to an arctic blast, but it undercuts and ruins the party.

[MR.SNOWMIZER]

Nam never gets credit. It does good with these patterns.

[Esquimalt]

The GFS ensembles getting good. The warmest member here, #16, is 3.0˚ at 850 mb.

[MossMan]

The GFS ensembles getting good. The warmest member here, #16, is 3.0˚ at 850 mb.

Could you post Seattle’s? My link is not working for some reason.

[SilverFallsAndrew]

18z ensembles maybe a touch milder, but still cooler than average.

[Deweydog]

Today is cooler than average.

[SilverFallsAndrew]

Really interesting 500mb pattern progression on the FV-3.

[Frontal Snowsquall]

It could be argued that solar minimum is the reason the SSW was able to occur, though. The photochemical effects on the thermal wind (in tandem w/ QBO) is not negligible, to say the least.

 

In fact, the wave driving that kicked off the SSW wasn’t all that strong..however it was amplified within the stratosphere, almost like an echo chamber. Part of this can be explained via the QBO state/MQI, however, similar cases have tended to fail during solar maximum.

 

So I have little doubt that the Sun played a role in allowing the SSW to occur in the first place.

I see. You know more than me about this kind of stuff so I won't question it.

 

What comes to my mind though is 1968-69, it was high solar and there was a big time SSW event that occurred that winter.

 

I agree though that your chances of being colder and snowier increase with low solar.

[Timmy Supercell]

Nice amount of moisture on KMAX. Looks nice. Too bad it's not a straight westerly shot, this would already have climbed on over to the other side of the mountains a while back.

 

[MR.SNOWMIZER]

FV-3 is pretty good late next week. Then gets VERY close to an arctic blast, but it undercuts and ruins the party.

For everone?? Slams the northern part of washington with heavy snow

[Frontal Snowsquall]

The 12z EPS keeps the -NAM/-PNA going thru D10-15.

 

EPS has been insanely consistent. It has literally not wavered once.

 

Its going to be a cold month.

Yeah, I've never seen this level of consistency before with the EPS this far out. Just a very strong signal.

[Gradient Keeper]

Solid discussion from PDX NWS

 

Later Sat night, and especially on Sunday, will see another upper low

pull out of British Columbia and drop south along the Pac NW coast.

This low will tug moisture back across the area, with increasing

showers. Snow levels will gradually lower, but will stay at 1500 to

2500 feet, highest over Oregon Cascades. All models show some low

sitting along or just off the Oregon coast later Sun night, and then

dumb-belling the low back to the west-northwest on Mon. All do show a

frontal boundary arcing northward from Astoria back to the Oregon

Cascades. But, details still fuzzy, as decent amount of model

inconsistency in the movement of the low, which will have direct

impacts on the potential lowland snow.

 

NAM is the most aggressive, showing lot more in way of offshore flow

through the Columbia Gorge. GFS not so much, with a bit slower trend.

But, it is now starting to follow a NAM trajectory, and keeps the low

a but closer to shore before sending the low back to the WNW on Mon

am. This would favor tad more offshore flow than earlier model runs,

and thus similar trend to that of NAM. Now, the ECMWF seems be

playing the "in between models" role, and is not all that helpful.

So, will trend more towards NAM at this point.

 

This trend will go with showers Sun night into Mon, with snow levels

gradually lowering to surface for the interior after 1 or 2 am Mon,

and down to sea level to 500 feet along the coast. Seems the primary

band of precipitation will be with the arcing frontal boundary, which

will nearly stall for a time Mon am over far southwest Washington

into extreme northwest Oregon. This will likely be the jackpot for

low elevation snowfall, with 2 to 3 inches possible between

Vader/Castle Rock and Woodland/Scappoose area. Bit to the south, snow

potential for 0.5 to 2.0 inches for Portland/Vancouver metro, with

heaviest to the north and west. Farther south, generally less than an

inch for Willamette Valley. But, could see local spots where may get

an inch or two on higher hills. Coast Range generally 3 to 6 inches

of snow, and same for the Cascades. But, little if any snow expected

to accumulate along the coast under 500 feet.

 

Now for the big caveat: Unfortunately, this is not a classic snow

situation, where get cold east winds and moisture at the same time.

Rather, it is showery in nature, with cooling temperatures aloft.

Accumulations will be spotty in nature for most areas. All will

depend on where the showers set up, and how long they persist over an

area. As we progress into the weekend, confidence should increase,

and model volatility will settle down, with better idea of what snow

can be expected, where, and when. But for now, those with travel

plans should be prepared for potential of snow covered roads late Sun

night through Mon. Again, alot forecasts are likely to change, so

stay tuned for the latest. Rockey.

Very interesting. NAM sounds similar to the WRF.

 

00z GFS in 3 hours 28 minutes

[SilverFallsAndrew]

Incredibly cold air in Central BC on the FV-3.

[Frontal Snowsquall]

Year without a summer!!

Now let's not go that far!

[SilverFallsAndrew]

For everone?? Slams the northern part of washington with heavy snow

 

Yes, there is. But the arctic air is bottled up by the undercutting energy. 

 

If it doesn't undercut it is a full on blast...Maybe I should have just phrased it that way.

[Frontal Snowsquall]

This might be the closest thing we've had as far as long lasting cool to cold since 2008. It looks like chances for snow every few days or so.

[#10127] You have reached your quota of positive votes for the day

[TT-SEA]

.62 at SEA so far today.

 

Almost 20% of the average rain for the entire month of February.

[Frontal Snowsquall]

lol

1969

[#10127] You have reached your quota of positive votes for the day

[Frontal Snowsquall]

I've a hunch this will be the longest thread of the season.

I leave to do some work for an hour and now I can't keep up.

[Requiem]

Well, things seem a lot better, I apologize for being a bit hasty yesterday. It appears this is a long period of small to decent snow chances, so yay! But I stand by my jealousy of CA right now, 65 gusts are cool.

[Frontal Snowsquall]

I know some of you like to follow the PNA.

 

[#10127] You have reached your quota of positive votes for the day

[SilverFallsAndrew]

These model runs are more fun than watching karma ***** slap Governor Northam. 

[Omegaraptor]

Is this Feb just going to make up for Nov-Jan all at once?

[James Jones]

.62 at SEA so far today.

 

Almost 20% of the average rain for the entire month of February.

 

Goes to show how overstated our reputation for rain is.