Part I - January 2020 Weather Discussion for the PNW

[mtep]

Would anyone mind posting the total snowfall individual member Euro for BLI? 

[Frontal Snowsquall]

New 7 day from Mark!

 

"With colder air coming in around next Wednesday, the possibility of a region-wide or metro-wide snow/ice event (or storm) is climbing. Each weather model handles the setup a bit different. Some hint we just get a little snow, others go for a major snow/ice storm. It’s still 6 days away so we have lots of time to figure it out. Just like we mentioned yesterday, you should be thinking ahead that some sort of snow/ice event could alter your plans midweek."

 

[Perturbed Member]

Mark?

[TacomaWaWx]

36 here in Tacoma. 38/30 spread today.

[Frontal Snowsquall]

Mark?

Yeah, I think it's from him. He posted an update at 4:30pm on the kptv weather page. What's funny is I saved the image on imgur and it's a bit different from the pic you have from the website. The snow graphics are slightly different. So he must have been editing it lol

[Deweydog]

The fact Mark put the flakes on the left and rain drops on the right for Monday is VERY telling.

 

What a dirt bag...

[TigerWoodsLibido]

45/36 for a 40.5 avg.  Should be just a smidgen above normal for the date so baby steps.

[runninthruda206]

Nasty looking snow shadow over central sound area... Please re-calculate cpu.

[Perturbed Member]

We are gonna be paying PDX back for last year this time.

 

It all comes back around.

 

Not if the 18z GFS is close to right. Snow for everyone. 

[Frontal Snowsquall]

Rod going with 40/35, 32/26, 28/23 on Mon-Wed for PDX.

 

Monday Night: Snow showers expected, possible accumulations by morning at lowest elevations.

 

Tuesday: Possible snow accumulation early morning, snow showers likely during the day.

 

Tuesday Night: Snow showers.

 

Wednesday: Mostly cloudy with snow flurries. Very cold temperatures are expected with gusty east winds.

 

Wednesday Night: Snow may increase overnight with possible accumulations into Thursday morning.

 

http://portlandweather.com/areas/portland-7-day

Rod going with 29/26 on Thursday.

[bainbridgekid]

18z ECMWF shows lower heights in OR and a stronger push of Arctic air through WA/MT compared to the 12z at hour 78...

 

Screen Shot 2020-01-09 at 5.41.19 PM.png

Does it still track Sunday's system North around the Canadian border?

[luvssnow_spokane]

If this doesn't smell like big regional snowstorm, I dont know what does.

A snowman ️ Fart?

[The Swamp]

Nice!!

Terrible map for central/south sound. Screw job.

[Perturbed Member]

PDX NWS thoughts, nothing we didn't already know but some interesting bits:

 

Monday Night - Tuesday

 

The exact surface low location
will have a significant impact on lowland snow potential. Forecast
850 mb temps fall to around -14C at KDLS to -8C at KPDX 12Z Tue.
This would definitely be cold enough for snow to the valley floor
north of about KSLE, especially with low-level offshore flow
developing through the Gorge.

There appears to be a precipitation lull Tue afternoon through Wed
morning, but plenty of uncertainly regarding the location of the
arctic boundary. The ECMWF continues to keep this boundary more
north than the GFS. Models typically do not handle the arctic
boundary all that well.

 

 

Wednesday

 

Should the ECWMF verify, there is the
potential for a significant over-running frozen/freezing precip event
for the north half of the forecast area. As an example, the 12Z
ECMWF snowfall accumulation for KPDX shows several members with 10+
inches total between Wed morning through Thu. However, there is
considerable variance among the individual ECMWF members Wed night
through Thu, with several showing no obvious surface low circulation
off the coast. To make matters even more confusing, the NBM
indicates a 50th percentile 24-hr snowfall 12Z Wed through 12Z Thu
for KPDX around 10 inches. The 90th percentile value is an
astonishing 15 inches, with at least a foot extending southward to
KEUG. Of course, considerable uncertainty exists beyond Mon and
forecast details will change over the next few days. Weishaar

 

 

They claim several EPS members show no low on Wednesday? I would assume it must be very few.

[TigerWoodsLibido]

Down to 43F with mostly cloudy skies.  Nice night.

[Front Ranger]

On the 18Z GFS... this is the frame that would bring the most snow in my area.

 

Strong onshore flow in a c-zone with cold air pouring in behind the low. No other period in the entire run would be as snowy... if it all verified.

 

Haven't you learned by now how useless these snow maps are for your area?

[The Swamp]

What's up with the Seattle NWS?  Where are they on the impending battle of cold vs warm?

 

Haven't checked the AFD.  Are they still gnashing their teeth and delaying the afternoon goodies?

 

There are a lot of homeless street people who could benefit from a little heads up on this .  The City of Seattle might need to open up some emergency shelters.  Not just for the snow, but potential cold.

 

They will probably put out a statement that reads "some computer model said some things.......Kovacik"   ha ha ha ha ha ha ha ha!

[seattleweatherguy]

What's up with the Seattle NWS?  Where are they on the impending battle of cold vs warm?

 

Haven't checked the AFD.  Are they still gnashing their teeth and delaying the afternoon goodies?

 

There are a lot of homeless street people who could benefit from a little heads up on this s**t.  The City of Seattle might need to open up some emergency shelters.  Not just for the snow, but potential cold.

 

They will probably put out a statement that reads "some computer model said some things.......Kovacik"   ha ha ha ha ha ha ha ha!

rea Forecast Discussion

National Weather Service Seattle WA

450 PM PST Thu Jan 9 2020

 

.SYNOPSIS...A strong frontal system will reach the area on Friday,

bringing another round of lowland rain, heavy mountain snow, and

windy conditions to the region. Cold air will move south into the

area starting Sunday night and cold fraser outflow winds are

likely early next week. There will be a chance of snow for the

lowlands of Western Washington from about Sunday night through at

least the middle of next week.

 

&&

 

.SHORT TERM /TONIGHT THROUGH SUNDAY/...The next system will

approach the coast late tonight into Friday and bring scattered

showers to the region by early Friday morning. Friday's system

will be rather well-organized and will bring several potential

impacts to the region, including:

 

Lowland Snow: With snow levels 500 feet or lower Friday morning,

there is roughly a 50 percent chance of precipitation falling as

snow versus rain for areas north of Everett and a 30 percent

chance for the western Kitsap peninsula, Mason county, and areas

near Olympia. With chances less than 20 percent throughout the

rest of the lowlands. Any lowland snow will transition to rain by

late morning, as snow levels increase rapidly with this incoming

system.

 

Lowland rain: Widespread rain will move into the western

Washington lowlands, with QPF amounts ranging from half an inch

to an inch and a half. Roadways could be slick at times.

 

Mountain Snow: Snow levels will rise to 1500-3000 feet across the

region by the afternoon hours. Snow accumulations will be 6-18

inches elevations above 2000 feet in the Cascades and 18 to 30

inches for elevations above 3000 feet. The Olympics will see

anywhere from 12-24 inches. The winter storm watches have been

upgraded to warnings for both the Olympics and the Cascades. In

addition to this, the Northwest Avalanche Center expects dangerous

to very dangerous avalanche conditions to develop on Friday and to

linger throughout the weekend.

 

Winds: Southerly winds will pick up as the frontal system

approaches the region, with winds reaching 30 to 40 mph, and

gusts to 50 to 60 mph. Highest gusts will be likely over and near

the water. Peak winds will occur early Friday morning through the

early afternoon for areas along the north and central coast and

areas from Whidbey Island north.

 

High Seas: Building seas along the coast into Saturday with

impacts expected, including hazardous surf resulting in some

coastal erosion. See marine section below for further details.

 

Continued River Flooding: With flooding continuing along the

lower Chehalis River, additional rainfall will likely prolong

river flooding. With snow levels higher near the Olympics, could

see a rise on the Skokomish. See the hydrology section below for

further details.

 

Showers will linger into the weekend, with Saturday continuing

to look wet, especially across the mountains. An arctic front

will drop down from British Columbia on Sunday, bringing with it

cool Fraser outflow, much cooler temperatures, and the potential

for lowland snow into next week.

 

.LONG TERM /MONDAY THROUGH THURSDAY/...A pattern change is on tap

for next week, with significantly cooler temperatures expected across

the region. Have opted for the ensemble means in the afternoon

forecast package for now, where highs look to stay below freezing

Tuesday and Wednesday. With cool temperatures and snow levels

below 500 feet for the lowlands, any precipitation that we would

see would be in the form of snow. However, there remains low

confidence regarding the timing, placement, and accumulations.

The big question will be the moisture associated with incoming

systems. Guidance continues to suggest that the bulk of the

moisture associated with the systems Monday and Tuesday will

remain to our south. Could still see some moisture skirt past the

southern portion of the CWA, so have maintained chance of POPs in

the long term for now. Models still disagree on timing and track

of the system next Wednesday, however ensembles continue to hint

that this may be the next best chance of snow for the lowlands. 14

 

&&

[Frontal Snowsquall]

A snowman ️ Fart?

[The Swamp]

rea Forecast Discussion

National Weather Service Seattle WA

450 PM PST Thu Jan 9 2020

 

.SYNOPSIS...A strong frontal system will reach the area on Friday,

bringing another round of lowland rain, heavy mountain snow, and

windy conditions to the region. Cold air will move south into the

area starting Sunday night and cold fraser outflow winds are

likely early next week. There will be a chance of snow for the

lowlands of Western Washington from about Sunday night through at

least the middle of next week.

 

&&

 

.SHORT TERM /TONIGHT THROUGH SUNDAY/...The next system will

approach the coast late tonight into Friday and bring scattered

showers to the region by early Friday morning. Friday's system

will be rather well-organized and will bring several potential

impacts to the region, including:

 

Lowland Snow: With snow levels 500 feet or lower Friday morning,

there is roughly a 50 percent chance of precipitation falling as

snow versus rain for areas north of Everett and a 30 percent

chance for the western Kitsap peninsula, Mason county, and areas

near Olympia. With chances less than 20 percent throughout the

rest of the lowlands. Any lowland snow will transition to rain by

late morning, as snow levels increase rapidly with this incoming

system.

 

Lowland rain: Widespread rain will move into the western

Washington lowlands, with QPF amounts ranging from half an inch

to an inch and a half. Roadways could be slick at times.

 

Mountain Snow: Snow levels will rise to 1500-3000 feet across the

region by the afternoon hours. Snow accumulations will be 6-18

inches elevations above 2000 feet in the Cascades and 18 to 30

inches for elevations above 3000 feet. The Olympics will see

anywhere from 12-24 inches. The winter storm watches have been

upgraded to warnings for both the Olympics and the Cascades. In

addition to this, the Northwest Avalanche Center expects dangerous

to very dangerous avalanche conditions to develop on Friday and to

linger throughout the weekend.

 

Winds: Southerly winds will pick up as the frontal system

approaches the region, with winds reaching 30 to 40 mph, and

gusts to 50 to 60 mph. Highest gusts will be likely over and near

the water. Peak winds will occur early Friday morning through the

early afternoon for areas along the north and central coast and

areas from Whidbey Island north.

 

High Seas: Building seas along the coast into Saturday with

impacts expected, including hazardous surf resulting in some

coastal erosion. See marine section below for further details.

 

Continued River Flooding: With flooding continuing along the

lower Chehalis River, additional rainfall will likely prolong

river flooding. With snow levels higher near the Olympics, could

see a rise on the Skokomish. See the hydrology section below for

further details.

 

Showers will linger into the weekend, with Saturday continuing

to look wet, especially across the mountains. An arctic front

will drop down from British Columbia on Sunday, bringing with it

cool Fraser outflow, much cooler temperatures, and the potential

for lowland snow into next week.

 

.LONG TERM /MONDAY THROUGH THURSDAY/...A pattern change is on tap

for next week, with significantly cooler temperatures expected across

the region. Have opted for the ensemble means in the afternoon

forecast package for now, where highs look to stay below freezing

Tuesday and Wednesday. With cool temperatures and snow levels

below 500 feet for the lowlands, any precipitation that we would

see would be in the form of snow. However, there remains low

confidence regarding the timing, placement, and accumulations.

The big question will be the moisture associated with incoming

systems. Guidance continues to suggest that the bulk of the

moisture associated with the systems Monday and Tuesday will

remain to our south. Could still see some moisture skirt past the

southern portion of the CWA, so have maintained chance of POPs in

the long term for now. Models still disagree on timing and track

of the system next Wednesday, however ensembles continue to hint

that this may be the next best chance of snow for the lowlands. 14

 

&&

 

 

ha ha ha ha......thanks

[MikeInEverett]

Can we please get the hydro portion of the discussion?

[Blizzard777]

I need a new snow shovel...but I'm nervous.  I would feel pretty silly buying it, then having to put it away in the basement because it's 38 degrees and drizzling next week in SE Portland.

 

But what if I need one and they're all sold out?  

Such torment !!!

Yield to the shovel quickly, not worth the emotional stress

[Weiner Warrior]

rea Forecast Discussion

National Weather Service Seattle WA

450 PM PST Thu Jan 9 2020

 

.SYNOPSIS...A strong frontal system will reach the area on Friday,

bringing another round of lowland rain, heavy mountain snow, and

windy conditions to the region. Cold air will move south into the

area starting Sunday night and cold fraser outflow winds are

likely early next week. There will be a chance of snow for the

lowlands of Western Washington from about Sunday night through at

least the middle of next week.

 

&&

 

.SHORT TERM /TONIGHT THROUGH SUNDAY/...The next system will

approach the coast late tonight into Friday and bring scattered

showers to the region by early Friday morning. Friday's system

will be rather well-organized and will bring several potential

impacts to the region, including:

 

Lowland Snow: With snow levels 500 feet or lower Friday morning,

there is roughly a 50 percent chance of precipitation falling as

snow versus rain for areas north of Everett and a 30 percent

chance for the western Kitsap peninsula, Mason county, and areas

near Olympia. With chances less than 20 percent throughout the

rest of the lowlands. Any lowland snow will transition to rain by

late morning, as snow levels increase rapidly with this incoming

system.

 

Lowland rain: Widespread rain will move into the western

Washington lowlands, with QPF amounts ranging from half an inch

to an inch and a half. Roadways could be slick at times.

 

Mountain Snow: Snow levels will rise to 1500-3000 feet across the

region by the afternoon hours. Snow accumulations will be 6-18

inches elevations above 2000 feet in the Cascades and 18 to 30

inches for elevations above 3000 feet. The Olympics will see

anywhere from 12-24 inches. The winter storm watches have been

upgraded to warnings for both the Olympics and the Cascades. In

addition to this, the Northwest Avalanche Center expects dangerous

to very dangerous avalanche conditions to develop on Friday and to

linger throughout the weekend.

 

Winds: Southerly winds will pick up as the frontal system

approaches the region, with winds reaching 30 to 40 mph, and

gusts to 50 to 60 mph. Highest gusts will be likely over and near

the water. Peak winds will occur early Friday morning through the

early afternoon for areas along the north and central coast and

areas from Whidbey Island north.

 

High Seas: Building seas along the coast into Saturday with

impacts expected, including hazardous surf resulting in some

coastal erosion. See marine section below for further details.

 

Continued River Flooding: With flooding continuing along the

lower Chehalis River, additional rainfall will likely prolong

river flooding. With snow levels higher near the Olympics, could

see a rise on the Skokomish. See the hydrology section below for

further details.

 

Showers will linger into the weekend, with Saturday continuing

to look wet, especially across the mountains. An arctic front

will drop down from British Columbia on Sunday, bringing with it

cool Fraser outflow, much cooler temperatures, and the potential

for lowland snow into next week.

 

.LONG TERM /MONDAY THROUGH THURSDAY/...A pattern change is on tap

for next week, with significantly cooler temperatures expected across

the region. Have opted for the ensemble means in the afternoon

forecast package for now, where highs look to stay below freezing

Tuesday and Wednesday. With cool temperatures and snow levels

below 500 feet for the lowlands, any precipitation that we would

see would be in the form of snow. However, there remains low

confidence regarding the timing, placement, and accumulations.

The big question will be the moisture associated with incoming

systems. Guidance continues to suggest that the bulk of the

moisture associated with the systems Monday and Tuesday will

remain to our south. Could still see some moisture skirt past the

southern portion of the CWA, so have maintained chance of POPs in

the long term for now. Models still disagree on timing and track

of the system next Wednesday, however ensembles continue to hint

that this may be the next best chance of snow for the lowlands. 14

 

&&

I like to quote these extra long ones

[TigerWoodsLibido]

[MikeInEverett]

All I see when I look at this graph is GFS Ensembles..

I think I’m going nuts

 

[Weiner Warrior]

Moisture coming in to the coast. Already pretty cold up in Seattle with the moon popping out. Thinking it might cool down enough before this moisture comes in.

[Kayla]

Does it still track Sunday's system North around the Canadian border?

 

Yeah the Sunday low track looks unchanged compared to the 12z.

[MossMan]

Currently 33.4 degrees here and cloudy.

Had a high of 36 and a low of 30.

1” of snow between last evening and this morning.

.15” of melted snow from the rain gauge.

[The Swamp]

Shannon Odonnel says we could get a "sloppy inch" tonight.

[MossMan]

Shannon Odonnel says we could get a "sloppy inch" tonight.

My inch last night actually was not too sloppy!

[MossMan]

This and cloud maps.

 

If people were fawning all over the radar maps and for big snow, he'd be quick to point how how they don't capture the reality of the situation.

 

Some people wonder why we are all hard on Tim, it isn't that he is being the Psion of weather discussion in a noisy room of disruptive weenies, its that he just serves as a disruptive force. See last years WDOT snow camera crisis.

 

But whatever, I'm a crappy admin and we are all probably over excitable for what will be a slushy skiff and blah temps. As I was reminded at work today, normal people don't get excited over the idea that they are going to probably have a hard time getting to work and that they might have to figure out childcare or miss out on a day of pay.

Most “normal” people have enjoyed the split flow winter from what I keep hearing. They are really missing out not being a weather weenie!

[Blizzard777]

36 here in Tacoma. 38/30 spread today.

39/30 here

.04

[TigerWoodsLibido]

Vikings @ Hawks a week from Sunday. Hopefully still wintry then.

[wxmet]

NAM 00z looks further south with the arctic front on Sunday.

[The Swamp]

My inch last night actually was not too sloppy!

I can do wonders with a sloppy inch.  Heck, I made a hail monster with the last dump of hail we got.

 

Give me that sloppy inch Shannon.  Give it to me!

[GHweatherChris]

I can do wonders with a sloppy inch. Heck, I made a hail monster with the last dump of hail we got.

 

Give me that sloppy inch Shannon. Give it to me!

Dirty old man lol

[TigerWoodsLibido]

NAM 00z looks further south with the arctic front on Sunday.

Good luck!!

[GHweatherChris]

Here's a weather briefing from NWS Seattle.

 

Sounds kind of like an internal/professional briefing that they made public.

 

Not a ton of new information but thought I would share anyways.

 

Now thats a conference call I could enjoy, thanks for sharing.

[snow_wizard]

It would appear the NWS is fully on board with winter weather next week!  Lots of snow mentioned and cold temperatures.  I was happy to see the 18z GFS go colder again after a few slightly milder runs.  It also indicated a longer cold snap once again.  The Euro snowfall maps show pretty much everyone on this forum will do pretty well over the next week.  I love seeing the low 20s it shows for afternoon temps on Wednesday!  Obviously the models are still in flux and top tier stuff could be on the table.

[runninthruda206]

NAM 00z looks further south with the arctic front on Sunday.

 

AMAZIN!