December 2023 Weather in the PNW

[Winterdog]

Only got down to 37 for a low, currently 38 with light rain at times.  I'm expecting our front yard to become a swamp over the next few days.  

[umadbro]

11 minutes ago, Phil said:

https://x.com/climatologist49/status/1730636594565312946?s=46&t=656Z973wLtGKaIyhhq_7QQ

 GlObAl BoIlIng!¡

[SnowWillarrive]

2 hours ago, TT-SEA said:

Maybe half an inch here... hard to tell.  Those are our cat's paw prints in the snow as he excitedly rushed outside this morning and then regretted it and came back begging to get inside.  

Did it snow on the valley floor of NB?

[TT-SEA]

27 minutes ago, SnowWillarrive said:

Did it snow on the valley floor of NB?

I think there was a little snow falling but nothing was sticking.   

[MWG]

A little breezy now but we are up to 43F now.

[SnowySeeker]

Low of 39f, currently 43 and partly sunny

[SouthHillFrosty]

51 minutes ago, SnowWillarrive said:

Did it snow on the valley floor of NB?

Did it snow out towards Ravensdale? 

[LowerGarfield]

Snow is now falling at a moderately higher rate now and getting new stickage. Still expecting to not last long but enough to start accumulation on my car again and the very edge of the highway.

[LowerGarfield]

[Phishy Wx]

Moderate Snow, 28

 

 

 

 

[RentonHill]

Pretty decent signal for first/second week of January on today's extended EPS SSW-ghetti

[Phishy Wx]

Snow Globe conditions.  29

[MossMan]

Skykomish looks fun right now! 

 

[SnowWillarrive]

1 hour ago, SouthHillFrosty said:

Did it snow out towards Ravensdale? 

No. I think there were a few flakes last night. But nothing fun. I can see snow on hills near my home. 

[Thermal Trough]

13 hours ago, TigerWoodsLibido said:

Buckle up...

Here is for a December to Remember!  

[Cascadia_Wx]

That was quick. PDX already up to 50. It was a nice run of cold. It’s likely that every day for the first week of the month will be 50+ there, with maybe even a 60 or two thrown in there early next week. Then hopefully another cooling trend.

48/36 spread here so far today. Rain at times with some heavy downpours this morning. Over a half inch of rain today already, with plenty more on the way. Ended November with close to 6” of rain, good to see.

 

[Port Angeles Foothiller]

EPS and GEFS both shifting to a nice looking pattern around the 12-14 day window. 

[TT-SEA]

46 minutes ago, MossMan said:

Skykomish looks fun right now! 

 

Basically the same elevation as my area but totally different as is often the case.  44 and windy here with no snow.   Protected valleys are a snow lovers paradise.  

[seattleweatherguy]

https://forecast.weather.gov/showsigwx.php?warnzone=WAZ556&warncounty=WAC033&firewxzone=WAZ657&local_place1=Bothell WA&product1=Wind+Advisory&lat=47.7624&lon=-122.2058
 

URGENT - WEATHER MESSAGE
National Weather Service Seattle WA
1023 AM PST Fri Dec 1 2023

WAZ504-507-509>511-514-555-556-558-559-020315-
/O.NEW.KSEW.WI.Y.0019.231202T0700Z-231202T1400Z/
Southwest Interior-Everett and Vicinity-Tacoma Area-
Admiralty Inlet Area-Hood Canal Area-
Eastern Strait of Juan de Fuca-East Puget Sound Lowlands-
Bellevue and Vicinity-Seattle and Vicinity-Bremerton and Vicinity-
Including the cities of Olympia, Lacey, Tumwater, Everett,
Edmonds, Lynnwood, Marysville, Tacoma, Port Townsend, Shelton,
Sequim, Covington-Sawyer-w, Maple Valley, Monroe, Prairie Ridge,
Enumclaw, Bonney Lake, Woodinville, Redmond, Kirkland, Bothell,
Kenmore, Newport Hills, Sahalee, Pine Lake, Seattle, Bremerton,
and Silverdale
1023 AM PST Fri Dec 1 2023

...WIND ADVISORY IN EFFECT FROM 11 PM THIS EVENING TO 6 AM PST
SATURDAY...

* WHAT...South winds 30 to 35 mph with gusts up to 50 mph
  expected.

* WHERE...Southwest Interior, Everett and Vicinity, Tacoma Area,
  Admiralty Inlet Area, Hood Canal Area, Eastern Strait of Juan
  de Fuca, East Puget Sound Lowlands, Bellevue and Vicinity,
  Seattle and Vicinity and Bremerton and Vicinity.

* WHEN...From 11 PM this evening to 6 AM PST Saturday.

* IMPACTS...Gusty winds could blow around unsecured objects.
  Tree limbs could be blown down and a few power outages may
  result.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Use extra caution when driving, especially if operating a high
profile vehicle. Secure outdoor objects.

&&

$$

[Phishy Wx]

intensity really increased the last hour or so, probably approaching 4"

Moderate to Heavy Snow, 30

 

[Doinko]

22 minutes ago, Phishy Wx said:

intensity really increased the last hour or so, probably approaching 4"

Moderate to Heavy Snow, 30

 

That seems like the upper end of predicted totals?

[RentonHill]

nothing more reliable than two GFS runs in a row showing the same thing 300 hours out! 

[Phishy Wx]

Snow has stopped for now.  A decent stack up so far.

 

 

[SouthHillFrosty]

13 minutes ago, RentonHill said:

nothing more reliable than two GFS runs in a row showing the same thing 300 hours out! 

A SSW? LFG. Doesn’t it take 4-6 weeks to have an impact?

[Phishy Wx]

2 minutes ago, SouthHillFrosty said:

A SSW? LFG. Doesn’t it take 4-6 weeks to have an impact?

yup, late January fun and games.  been looking at that period for a few weeks

[Phishy Wx]

calling for an additional 1-4" here before it warms tomorrow afternoon

[luvssnow_spokane]

Got about 4 inches here in North Spokane. LOVING it!!

[Phil]

28 minutes ago, RentonHill said:

nothing more reliable than two GFS runs in a row showing the same thing 300 hours out! 

That would be nice. And it’s early enough in the season that niño climo wouldn’t be overly hostile yet (for the NW) as coupling to the troposphere establishes heading into midwinter.

[Phil]

14 minutes ago, SouthHillFrosty said:

A SSW? LFG. Doesn’t it take 4-6 weeks to have an impact?

Not necessarily. Effects can be synchronous or lagged 8+ weeks depending on the nature of the SSW.

This setup is more favorable for faster propagation/better coupling to the troposphere thanks to QBO and WAFz conduits.

*If* it happens.

[Phil]

Insane Scandinavia ridge on the clown range drunkle.

If that actually verified, even strong niño climo could be thrown for a loop. Zero chance the PV would survive that. Just..wow.

[Ken in Wood Village]

The NWS finally issued it.

High Wind Watch

URGENT - WEATHER MESSAGE
National Weather Service Portland OR
223 PM PST Fri Dec 1 2023

ORZ006>008-WAZ039-021500-
/O.NEW.KPQR.HW.A.0001.231203T0900Z-231204T0300Z/
Greater Portland Metro Area-Central Willamette Valley-
South Willamette Valley-Greater Vancouver Area-
Including the cities of Hillsboro, Portland, Wilsonville,
Oregon City, Gresham, Troutdale, Salem, McMinnville, Woodburn,
Stayton, Dallas, Eugene, Springfield, Corvallis, Albany, Lebanon,
Vancouver, Battle Ground, Ridgefield, Washougal, Yacolt,
and Amboy
223 PM PST Fri Dec 1 2023

...HIGH WIND WATCH IN EFFECT FROM LATE SATURDAY NIGHT THROUGH
SUNDAY EVENING...

* WHAT...South winds 20 to 30 mph with gusts up to 50 mph
  possible.

* WHERE...In Oregon, Greater Portland Metro Area, Central
  Willamette Valley and South Willamette Valley. In Washington,
  Greater Vancouver Area.

* WHEN...From late Saturday night through Sunday evening.

* IMPACTS...Damaging winds could blow down trees and power
  lines. Widespread power outages are possible. Travel could be
  difficult, especially for high profile vehicles.

* ADDITIONAL DETAILS...A High Wind Watch means hazardous high
  wind conditions are favorable in and close to the watch area in
  the next 12 to 48 hours.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts and warnings for updates on this
situation. Fasten loose objects or shelter objects in a safe
location prior to the onset of winds.

[Ken in Wood Village]

It's amazing to see the storms lining up to impact the PNW!!

[Phil]

40 minutes ago, Ken in Wood Village said:

The NWS finally issued it.

High Wind Watch

URGENT - WEATHER MESSAGE
National Weather Service Portland OR
223 PM PST Fri Dec 1 2023

ORZ006>008-WAZ039-021500-
/O.NEW.KPQR.HW.A.0001.231203T0900Z-231204T0300Z/
Greater Portland Metro Area-Central Willamette Valley-
South Willamette Valley-Greater Vancouver Area-
Including the cities of Hillsboro, Portland, Wilsonville,
Oregon City, Gresham, Troutdale, Salem, McMinnville, Woodburn,
Stayton, Dallas, Eugene, Springfield, Corvallis, Albany, Lebanon,
Vancouver, Battle Ground, Ridgefield, Washougal, Yacolt,
and Amboy
223 PM PST Fri Dec 1 2023

...HIGH WIND WATCH IN EFFECT FROM LATE SATURDAY NIGHT THROUGH
SUNDAY EVENING...

* WHAT...South winds 20 to 30 mph with gusts up to 50 mph
  possible.

* WHERE...In Oregon, Greater Portland Metro Area, Central
  Willamette Valley and South Willamette Valley. In Washington,
  Greater Vancouver Area.

* WHEN...From late Saturday night through Sunday evening.

* IMPACTS...Damaging winds could blow down trees and power
  lines. Widespread power outages are possible. Travel could be
  difficult, especially for high profile vehicles.

* ADDITIONAL DETAILS...A High Wind Watch means hazardous high
  wind conditions are favorable in and close to the watch area in
  the next 12 to 48 hours.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts and warnings for updates on this
situation. Fasten loose objects or shelter objects in a safe
location prior to the onset of winds.

How do you get a high wind watch for 50mph gusts? That’s barely wind advisory criteria which is nationally standardized.

[Thermal Trough]

10 hours ago, Ken in Wood Village said:

Here comes the train of storms!!

Beautiful Java Jet!  

[Phishy Wx]

[Tyler Mode]

11 minutes ago, Phil said:

How do you get a high wind watch for 50mph gusts? That’s barely wind advisory criteria which is nationally standardized.

PDX does whatever.  The actual forecast only says 40 too.

[Brian_in_Leavenworth]

9 minutes ago, Phil said:

How do you get a high wind watch for 50mph gusts? That’s barely wind advisory criteria which is nationally standardized.

Guessing wet grounds and maybe trees that still have leaves can cause more problems than otherwise.  

Another example is that our criteria here in  Leavenworth for WSW's and WWA's is often lowered for the first winter storm of the year, so the context can alter their criteria a bit.  

Just a guess though 

.

[Poulsbo Snowman]

It's only a watch.  The criteria for a high wind warning is:

Sustained winds 40-73 mph (≥35 kts) for at least 1 hour; OR any gusts ≥ 58 mph (≥50 kts)

I surmise it will be upgraded to a warning once the criteria is met.  

[Phil]

This was the special weather statement updating a high wind warning here a few years back.

Even on this one they waited to pull the trigger on the HWW until the last minute. Never seen one issued for gusts < 60mph.

[Thermal Trough]

4 hours ago, RentonHill said:

Pretty decent signal for first/second week of January on today's extended EPS SSW-ghetti

 

1 hour ago, RentonHill said:

nothing more reliable than two GFS runs in a row showing the same thing 300 hours out! 

 

1 hour ago, SouthHillFrosty said:

A SSW? LFG. Doesn’t it take 4-6 weeks to have an impact?

 

1 hour ago, Phishy Wx said:

yup, late January fun and games.  been looking at that period for a few weeks

 

1 hour ago, Phil said:

Not necessarily. Effects can be synchronous or lagged 8+ weeks depending on the nature of the SSW.

This setup is more favorable for faster propagation/better coupling to the troposphere thanks to QBO and WAFz conduits.

*If* it happens.

A SSW can be a game changer in the Winter, especially if it’s a major one like what this one looks like it’s gonna be. A major SSW event can overpower an El Niño like in 1968-69. Sometimes it only takes 2 weeks to feel the downstream effects of an SSW and to deliver an Arctic Blast down to the continental USA. The January 2019 SSW is an example of this.