March 2020 Weather Discussion for the PNW

[SilverFallsAndrew]

12z has some goodies. LOL

 

[Jesse]

None that I’ve been bullish over.

 

This would be the final warming, technically. Where the vortex breaks up and is replaced by an anticyclone for the warm season. A “dynamic” final warming is analogous to a SSW, for all intents and purposes, though.

 

I understand the difference, but mechanically they are fairly similar.

[Jesse]

Pretty incredible how dry the models look. 2nd straight driest March ever is definitely in play.

 

The very dry month unfolding is definitely the biggest story right now.

[SilverFallsAndrew]

The very dry month unfolding is definitely the biggest story right now.

 

At some point you would hope we pay the piper for 3 straight dry years. 

[GHweatherChris]

At some point you would hope we pay the piper for 3 straight dry years.

Piper passed away on 7/31/15.

[SilverFallsAndrew]

Seems like some chilly weather is a real possibility at least. 

 

SLE hit freezing this morning. 

[TT-SEA]

At some point you would hope we pay the piper for 3 straight dry years. 

 

 

Portland was quite wet in 2017... 9 inches above normal for the year.

 

So technically its been 2 dry years at this point down there.

[SilverFallsAndrew]

Portland was quite wet in 2017... 9 inches above normal for the year.

 

So technically its been 2 dry years at this point down there.

 

Rain years 2017-18

2018-19

2019-20

 

We are almost done with the period we can make up much ground for the present water year. 

[TT-SEA]

12Z ECMWF still shows lowland snow on Friday into Saturday morning...

 

[SilverFallsAndrew]

12Z ECMWF still shows lowland snow on Friday into Saturday morning...

 

 

Hopefully it doesn't fall apart again during the work week.

[MossMan]

.11” on the day, 2.79” on the month, 20.99” on the year.

Sunny and 38 degrees currently.

[Phil]

I understand the difference, but mechanically they are fairly similar.

True. At least if it’s a dynamic final warming, as I’m sure you already know.

 

Non-dynamic final warmings aren’t all that interesting though. At least to me. Just withers away as solar radiative forcing alters the photochemically modulated boundary conditions through which thermal winds/etc operate under.

[TT-SEA]

Rain years 2017-18

2018-19

2019-20

 

We are almost done with the period we can make up much ground for the present water year. 

 

 

Ahhh... I see.   Very different in the Seattle area of course. 

 

Here are the last 5 rainy seasons in Seattle:

 

2015-16 - 44.52 inches (+12.50)  *wettest rainy season in history at the time*

 

2016-17 - 45.00 inches (+12.98)  *wettest rainy season in history*

 

2017 -18 - 37.27 inches (+5.25)

 

2018-19 - 28.62 inches (-3.40)

 

2019-20 to date -  27.56 inches (+2.20)

 

 

The cumulative surplus over the last 5 rainy seasons is +29.53 inches which is pretty amazing.  

 

Nature is a b*tch lately.   

[HighlandExperience]

12Z ECMWF still shows lowland snow on Friday into Saturday morning...

 

 

Already falling apart

[Phil]

The vortex is really just a chemical tornado, driven by the insolation gradient. Change that up and it can’t exist.

 

Which is why I’m sort of bullish here. The vortex will have to die at some point. And given its anomalously potent starting point leaves room for impressive wave dynamics (not to the ongoing O^3 depletion/night jet feedback loop still present to midwinter levels) I’m buying into the analogy “the bigger they are, the harder they fall” at this time of year”.

[Front Ranger]

Weather has been pretty pleasant in Tampa. Was muggy in the low 80s the first day, then a cold front on Friday knocked temps into the 60s with low humidity last couple days.

[Jesse]

12z Euro is a little wetter than the FV3 but that's not saying much.

[TT-SEA]

The coldest air bypasses WA on the 12Z ECMWF with the ULL heading southward offshore to our west next weekend and then comes inland to the south. 

 

Also a dry run overall for western WA.

[Phil]

But how this relates to PNW cold/timing of such depends on the EA-AMM/response from the tropics/MJO and the wave-cycle itself as seasons are changing. Tough call.

 

If there’s a cold air release, I think it’ll happen in April, or the end of March. Would not shock me if there’s some serious late season cold somewhere next month, but exactly where is tough to pin down this far in advance during the seasonal transition.

[Jesse]

Reload?! at hour 240.

[The Swamp]

I'm sure glad I didn't take my eye off the ball this season!  It should be making people wonder that I haven't just left the forum for the season like I usually do by now.  Pretty obvious this isn't business as usual.

Does someone write this stuff for you?  Often times It does't seem real.

[Jesse]

But how this relates to PNW cold/timing of such depends on the EA-AMM/response from the tropics/MJO and the wave-cycle itself as seasons are changing. Tough call.

 

If there’s a cold air release, I think it’ll happen in April, or the end of March. Would not shock me if there’s some serious late season cold somewhere next month, but exactly where is tough to pin down this far in advance during the seasonal transition.

 

I think this is called getting ahead of ourselves. We don't even know if there will be a DFW yet or not.

[Phil]

12z Euro is a little wetter than the FV3 but that's not saying much.

For whatever it’s worth, the ideal pattern to produce the dynamic final warming and maybe shake up some trends going into this seasonality change would be drier/meridional over the West during that process. So that might technically be a good thing. Wouldn’t be permanent.

 

That zonal pattern a few folks were semi-excited about during January ended up failing for the same reasons the inverse may succeed.

[Jesse]

For whatever it’s worth, the ideal pattern to produce the dynamic final warming and maybe shake up some trends going into this seasonality change would be drier/meridional over the West during that process. So that might technically be a good thing. Wouldn’t be permanent.

 

 

I almost forgot that it can be wet around here in May/June with ULLs. Summer starts around April 20 lately.

[Jesse]

Does someone write this stuff for you?  Often times It does't seem real.

 

I would like to see more snow monster and sun tan related content from him personally.

[TacomaWaWx]

Next 10 days look chilly. Lowland snow chances especially above 500’ aren’t dead just yet.

[Phil]

I think this is called getting ahead of ourselves. We don't even know if there will be a DFW yet or not.

True. Not trying to go all Jim on ya. But it’s not just a dynamic nowcast from me..I like the odds based on the ECMWF reanalysis for analogous QBOs w/ strong late winter vortexes like this. The dynamic FW success rate is over 50%.

 

https://www.geo.fu-berlin.de/en/met/ag/strat/produkte/northpole/index.html

[ShawniganLake]

For whatever it’s worth, the ideal pattern to produce the dynamic final warming and maybe shake up some trends going into this seasonality change would be drier/meridional over the West during that process. So that might technically be a good thing. Wouldn’t be permanent.

 

That zonal pattern a few folks were semi-excited about during January ended up failing for the same reasons the inverse may succeed.

January 2020 was a great month.

[TT-SEA]

January 2020 was a great month.

January 2020 featured a great week for places north of Seattle.

 

The majority of the month was a warm, rainy mess even up there.

[TacomaWaWx]

January 2020 was a great month.

even though we missed out on the real cold by 50 miles or so down here it was still an interesting month overall. Very wet, bit of snow and a wind event on the last night of the month.

[Phil]

True. Not trying to go all Jim on ya. But it’s not just a dynamic nowcast from me..I like the odds based on the ECMWF reanalysis for analogous QBOs w/ strong late winter vortexes like this. The dynamic FW success rate is over 50%.

 

https://www.geo.fu-berlin.de/en/met/ag/strat/produkte/northpole/index.html

Plus this is one of the cases where WPAC forcing would help w/ WAFz..and the Indo-West Pacific Warm Pool is as steroidal as it’s ever been in recorded history. Why not put it to use? Maybe drain that sucker a bit?

 

[ShawniganLake]

January 2020 featured a great week for places north of Seattle.

 

The majority of the month was a rainy mess even up there.

It was a stormy month. I like stormy in the winter. Rain, wind and snow. Obviously my opinion is different than others that live a few miles to the south, or people that don’t like heavy rain during the winter.

[TT-SEA]

It was a stormy month. I like stormy in the winter. Rain, wind and snow. Obviously my opinion is different than others that live a few miles to the south, or people that don’t like heavy rain during the winter.

 

 

Fair enough.   

[Jesse]

It was a stormy month. I like stormy in the winter. Rain, wind and snow. Obviously my opinion is different than others that live a few miles to the south, or people that don’t like heavy rain during the winter.

 

I enjoyed January 2020 from that standpoint as well. Lots of snow in the mountains and an unrelenting storm train the likes of which we hadn't seen in a while. Even though I personally didn't end up with much snow.

[Front Ranger]

But how this relates to PNW cold/timing of such depends on the EA-AMM/response from the tropics/MJO and the wave-cycle itself as seasons are changing. Tough call.

 

If there’s a cold air release, I think it’ll happen in April, or the end of March. Would not shock me if there’s some serious late season cold somewhere next month, but exactly where is tough to pin down this far in advance during the seasonal transition.

Bozeman.

[Phil]

January 2020 featured a great week for places north of Seattle.

 

The majority of the month was a warm, rainy mess even up there.

And that was despite vigorous tropospheric RWB activity that in many years would have delivered in a huge way.

 

I’m pretty confident January 2020 would have blown February 2019 (and any satellite era winter month) out of the friggin’ iceberg in terms of western cold if the TPV didn’t get flukily trapped over the Beaufort/Yukon domain during that crucial string of wavebreaks in late December/early January.

 

That was the event that ended winter, IMO. Once that happened, the TPV and strat vortex coupled like titanium, and there was no dislodging that sucker.

[ShawniganLake]

Fair enough.

I was probably trolling you a touch too. But it was an interesting month.

[Jesse]

And that was despite vigorous tropospheric RWB activity that in many years would have delivered in a huge way.

 

I’m confident January 2020 would have blown February 2019 (and any satellite era winter month) out of the friggin’ iceberg in terms of western cold if the TPV didn’t get flukily trapped over the Beaufort/Yukon domain during that crucial string of wavebreaks in late December/early January.

 

That was the event that ended winter, IMO. Once that happened, the TPV and strat vortex coupled like titanium, and there was no dislodging that sucker.

 

I wonder if there are other similarly long stories for the last 30-40 Januaries or so that have failed to deliver regionally around here.

[snow_wizard]

Nobody is going to talk me down from this.  I have a feeling the coming few weeks are going to ooze 19th century.  I haven't been this stoked about anything this time of year in ages if ever.  The potential is there for a number of cold duration and intensity to fall this month and maybe into April.  The -5 EPO being forecast the EPS is reason enough alone to know something highly unusual is unfolding.  It will be interesting to see if intrusions of chilly continental air even extend well into the spring.  I'm going to enjoy all of the unseasonably cold mins coming up, and snow is a definite possibility somewhere along the line as this unfolds.

[snow_wizard]

And that was despite vigorous tropospheric RWB activity that in many years would have delivered in a huge way.

 

I’m pretty confident January 2020 would have blown February 2019 (and any satellite era winter month) out of the friggin’ iceberg in terms of western cold if the TPV didn’t get flukily trapped over the Beaufort/Yukon domain during that crucial string of wavebreaks in late December/early January.

 

That was the event that ended winter, IMO. Once that happened, the TPV and strat vortex coupled like titanium, and there was no dislodging that sucker.

 

No doubt that event came very close.  Going forward I feel like we are still in a good place.  Not going to let a failed attempt or two spoil what appears to be a promising big picture.  I'm still very interested to see if we can get an AO crash and historic late cold wave or not.  Even without that the NW looks to have a cold March in the works.