[Missing] March 2022 PNW Wx Discussion

[SilverFallsAndrew]

2 minutes ago, TT-SEA said:

The March - May period was drier than normal at the Fern Ridge station in 2015, 2018, 2020, and 2021 (only slightly below normal in 2018 and 2020).

But spring was very wet in 2014, 2016, 2017, and 2019.  

I don't see a real trend toward dry springs at that station either... but last year was very dry.

IDK what to tell  you. I think we could just look at the drought map to see there is some kind of an issue. The biggest issue with the fires and all is probably how hot summers have been. No denying 2013-present has been a monumental torch during the summer months. 2016-17 had great snow pack and tons of precip, but we had a horrifically hot summer and awful fire season. So at the end of the day, that's probably the real issue. 

[Dave]

Last time I checked, the 30 year running average of annual precip was within an inch or two for Eugene vs Seattle. Seems about right. There's no question that there is an unfortunate trend of a drier era down here. 

[TT-SEA]

14 minutes ago, SilverFallsAndrew said:

IDK what to tell  you. I think we could just look at the drought map to see there is some kind of an issue. The biggest issue with the fires and all is probably how hot summers have been. No denying 2013-present has been a monumental torch during the summer months. 2016-17 had great snow pack and tons of precip, but we had a horrifically hot summer and awful fire season. So at the end of the day, that's probably the real issue. 

Yeah... the hot and dry summers are probably the real issue.     I don't see any decline in annual rainfall at the Fern Ridge station.    Actually the opposite.    That station is 39 inches above normal cumulative since 2014.     

Of course 2013 was very dry (like everywhere)... but 2010-12 was also very wet.  

Over the last decade (2012-2021) the Fern Ridge station is 48.89 inches above normal cumulatively.

[TigerWoodsLibido]

46F with some light rain. Over an inch on the day.

[TT-SEA]

00Z EPS is still wet in week 2 with zonal flow.    Control run looks the same... but a little less so than the 12Z run.

[Meatyorologist]

1 hour ago, Dave said:

Last time I checked, the 30 year running average of annual precip was within an inch or two for Eugene vs Seattle. Seems about right. There's no question that there is an unfortunate trend of a drier era down here. 

Ever since the wettest year on record, 1996, things have trended drier.

[Meatyorologist]

Meanwhile, annual precipitation has been steadily increasing in Seattle since the beginning of the 80s.

AGW is forcing the midlatitude baroclinic zone northward. Eugene is experiencing more influence from the subtropical Hadley cell downwelling (the same mechanism that keeps CA so dry), while Seattle is seeing more and more warm precipitation associated with atmospheric rivers. Warm air holds more water, hence the uptick in total precipitation. Seattle, now with that baroclinic zone displaced north, is stealing more and more frontal precip from Eugene.

In a strange sort of way Seattle is slowly stealing the Willamette Valley's weather.

[Meatyorologist]

I think this says it all... (Positive values mean Eugene is wetter than Seattle by that amount, negative values drier)

[TT-SEA]

4 hours ago, Meatyorologist said:

I think this says it all... (Positive values mean Eugene is wetter than Seattle by that amount, negative values drier)

Interesting.    Your analysis does seem to make sense...  but the Fern Ridge station does not show the same trend.    Maybe that station has issues.    What does it look like if you use Salem or Roseburg?

[AlTahoe]

8 hours ago, TT-SEA said:

Yeah... the hot and dry summers are probably the real issue.     I don't see any decline in annual rainfall at the Fern Ridge station.    Actually the opposite.    That station is 39 inches above normal cumulative since 2014.     

Of course 2013 was very dry (like everywhere)... but 2010-12 was also very wet.  

Over the last decade (2012-2021) the Fern Ridge station is 48.89 inches above normal cumulatively.

Could it be that the decades of overgrowth allowed to accumulate in the Forest are causing much bigger fires? 

I know in the Sierra it is one of the biggest factors. In the 1920's the forest averaged like 40 pines per Acre. Now we have 250+ per acre 

[SilverFallsAndrew]

Chilly morning, temp down to 36 as cooler air aloft moves in. Tomorrow May struggle to hit the lower 40s.

[MossMan]

Currently mostly cloudy, Smokey, and 39.

.34” so far on the day, .85” for the month, 11.37” for the year. 

[TacomaWaWx]

41 for the low…no rain since midnight. 

[Phil]

7 hours ago, Meatyorologist said:

Ever since the wettest year on record, 1996, things have trended drier.

There was a large shift in the general circulation(s) following the 1997/98 super niño, which has held to this day.

The transition was complete by 2000.  

[Phil]

7 hours ago, Meatyorologist said:

Meanwhile, annual precipitation has been steadily increasing in Seattle since the beginning of the 80s.

AGW is forcing the midlatitude baroclinic zone northward. Eugene is experiencing more influence from the subtropical Hadley cell downwelling (the same mechanism that keeps CA so dry), while Seattle is seeing more and more warm precipitation associated with atmospheric rivers. Warm air holds more water, hence the uptick in total precipitation. Seattle, now with that baroclinic zone displaced north, is stealing more and more frontal precip from Eugene.

In a strange sort of way Seattle is slowly stealing the Willamette Valley's weather.

The expanding (and slowing) of the Hadley Cell can also be attributed to the broadening and overall NE-ward displacement of the IPWP which isn’t necessarily AGW related (given it also appears to have a occurred during the 1000-1250AD timeframe, to an even more significant extent than today, which coincided with the multi-century megadrought(s) across western and central North America). These changes are also an AL/high latitude WAA machine that serves as a conduit to more frequent +TNH and/or +NAM.

It’s theoretically possible for the system to warm and for the Hadley Cells to contract (we see this with El Niño) however proxies suggest this does not happen on longer timescales (multidecadal or beyond). Every Holocene warm period seems to coincide with an expansion of the Hadley Cells, a broadening of the 4CH/drought conditions in western North America, and likely enhanced convection in the west-pacific extending into the off-equatorial domains, knowing how that teleconnects today.

[ShawniganLake]

1 hour ago, AlTahoe said:

Could it be that the decades of overgrowth allowed to accumulate in the Forest are causing much bigger fires? 

I know in the Sierra it is one of the biggest factors. In the 1920's the forest averaged like 40 pines per Acre. Now we have 250+ per acre 

Mother Nature is cleaning up our mess!

June is the most critical month for the fire season as far as weather goes for BC. A hot dry June is pretty much guaranteed to trigger an active fire season. Especially considering June is typically one of the wettest months of the year in parts of the interior

[Cascadia_Wx]

1 hour ago, AlTahoe said:

Could it be that the decades of overgrowth allowed to accumulate in the Forest are causing much bigger fires? 

I know in the Sierra it is one of the biggest factors. In the 1920's the forest averaged like 40 pines per Acre. Now we have 250+ per acre 

Dont see how that would cause hotter summers 

[Cascadia_Wx]

Ended up with .67” rain yesterday pretty big overachiever nice to see areas to the south did even better. 

About 3.5” of rain since the wet period started on Saturday here 

 

[Phil]

Also debatable as to how the acceleration of the BDC/mass circulation in the stratosphere has affected tropical convection/WPWP since the 1980s/90s. Uncertain, but there’s been some interesting research done on this topic in recent years, suggesting it could be a significant contributor to the observed changes in the tropics.

In which case, was it also a contributor to the other periods in the Holocene where similar large scale changes to z-cells have been documented? If so, what triggered it? Appears to be driven at least in part by changes in O^3/thermal winds and ENSO, which raises all kinds of questions about emergent states.

[Cascadia_Wx]

Beautiful sunny morning here 37 for a low 41 currently. Had a 53/45 spread yesterday 

[TT-SEA]

GFS seems to be slowly caving to the ECMWF/EPS... moving away from a very amplified and potentially cold scenario to more zonal flow and a wetter pattern overall.  

[Phil]

43 minutes ago, Eujunga said:

Perhaps worth noting is that just because certain atmospheric circulation pattern changes have occurred in the past without the benefit of AGW doesn't mean that there isn't an AGW component this time around. The Occam's Razor solution would seem to suggest that there very likely is (it stands to reason to injecting trillions of tons of CO2 into the atmosphere is probably going to affect it somehow).

In any case, it's all very complex and driven by factors we don't fully understand yet. Which is why I bristle when even some of the most reputable climate change scientists seem to buy into the notion that we can limit global warming by a precise number of degrees if we reduce carbon emissions by a certain amount.

Sorry for going a little O/T and treading into controversial waters, but I feel like it's pertinent to the changes I've observed in my backyard climatology (warmer and drier -- or maybe not drier, maybe I'm just imagining things).

It’s only logical that the changes in radiative fluxes due to increasing CO^2 are involved somehow. I would not doubt that at all. The question is how? And to what extent?

The problem (at this point) is the magnitude of the observed changes cannot be explained by CO^2/AGW alone. We are missing something big, whether it be a feedback related to AGW, or something else entirely (I tend to favor the latter, but we can’t know).

Also, keep in mind, these changes to the general circulation(s) began in the 19th century, or possibly earlier than that. Well before CO^2 was a factor.

And interestingly, we saw a temporary *reversal* in these trends from the 1940s to the 1970s, when CO^2 would have been more of a factor.

So at the very least, the driving mechanisms are pre-existing and the observed changes are state dependent. Whether AGW has somehow amplified the signal or changed the equation is not a question we can answer right now.

But assuming there is a link to AGW, and that it is most likely loose/peripheral, then there’s a decent chance it won’t maintain a grip on these evolutions of general states. Which ties back to the idea that both climate sensitivity and the transient response are state dependent.

[MossMan]

34 minutes ago, TT-SEA said:

GFS seems to be slowly caving to the ECMWF/EPS... moving away from a very amplified and potentially cold scenario to more zonal flow and a wetter pattern overall.  

Guess I can take the plow off my mower and put the mower deck back on. The growing season is coming! 

[TT-SEA]

3 minutes ago, MossMan said:

Guess I can take the plow off my mower and put the mower deck back on. The growing season is coming! 

Rapid turn around here from last week... from a frozen landscape and snow that was not melting even with sunshine to a green and wet landscape and grass that is definitely starting to shows signs of growing.     The transition was much slower in 2019.   We couldn't buy a raindrop that March.

[AlTahoe]

1 hour ago, Cascadia_Wx said:

Dont see how that would cause hotter summers 

They were talking about hotter summers leading to more forest fires. I think the temp of the summers doesn't really matter anymore. The forest are so overgrown we are getting explosive fires even when the conditions don't warrant it. 

[AlTahoe]

GFS is sticking to it's guns that March will give us next to nothing. Driest Jan-March on record is looking like a lock unless the end of the month surprises.  

[TT-SEA]

4 minutes ago, AlTahoe said:

GFS is sticking to it's guns that March will give us next to nothing. Driest Jan-March on record is looking like a lock unless the end of the month surprises.  

Pretty big shift up here over the last few runs.     The EPS has also been hinting at a ridge over CA pumping moisture into the PNW.

12Z GFS from yesterday on top and new 12Z GFS on the bottom.      Its quite different... but the result is the same in CA.

 

[AlTahoe]

13 minutes ago, TT-SEA said:

Pretty big shift up here over the last few runs.     The EPS has also been hinting at a ridge over CA pumping moisture into the PNW.

12Z GFS from yesterday on top and new 12Z GFS on the bottom.      Its quite different... but the result is the same in CA.

 

The direst Jan-March for Tahoe was in 1976 with 3.6" combined. We are at .8" right now with maybe .10" this weekend and then nothing being shown through mid March. Incredible. 

Also the last 2 winters featured less than 50% of normal precip for Jan - March

This year is looks to be in the less than 25% range. Pretty soon our summer months will have more precip from Monsoon activity than the heart of winter. 

[Cascadia_Wx]

1 hour ago, AlTahoe said:

They were talking about hotter summers leading to more forest fires. I think the temp of the summers doesn't really matter anymore. The forest are so overgrown we are getting explosive fires even when the conditions don't warrant it. 

There are a lot of factors seems like both probably play a role during the recent summers with lots of fires in the west heat and drought conditions have definitely warranted it 

[Front Ranger]

11 hours ago, SilverFallsAndrew said:

Salem had above average precip 2014-17, and was actually slightly above average in 2021. 

One of the reasons some of those years ended up below average up here is because the bulk of the precip came in the winter, we get a lot of precip in the spring here compared to the valley. So a parched May like we had in 2018 is only going to come in 1" or so below normal in the valley, but we usually get 5-6" of rain in May, so it's going to have a big impact on our seasonal total. 

 

Yep. Tim likes to make a big deal of wet years, but usually those are due to unusual wetness in the fall/winter, when people expect it to be wet anyway.

[Cascadia_Wx]

Euro still seems on board with zonal flow developing in the 8-10 day range GEM turned very wet starting well before day 10 

[The Blob]

6pm sunset tonight

[TT-SEA]

1 hour ago, Front Ranger said:

Yep. Tim likes to make a big deal of wet years, but usually those are due to unusual wetness in the fall/winter, when people expect it to be wet anyway.

Interesting.     So statistics don't matter and feelings are really the most important thing?   I will remember that in the COVID discussion.      People "expect" fall/winter to be wet so it doesn't matter if its much drier than average or much wetter than average because rain is rain.  I mean... I get it.  I would personally much rather have Nov-March be the statistically wetter than normal portion of the year.    But the increase in rainfall is still interesting.    

Average annual rainfall appears to be increasing up here.   And summers are generally becoming warmer.    Those things seem to be true and in line with predictions of a warming climate locally.   

But we have also had some very wet springs in the last 10-15 years.   And even some wet summers like 2019.

[MWG]

Oof

I hope we do get more rain! February looked so bad. Looking at this 2013 was a bad year and I remember that was the first year I experienced with smoke in the valley for days. 

[TT-SEA]

1 hour ago, Cascadia_Wx said:

Euro still seems on board with zonal flow developing in the 8-10 day range GEM turned very wet starting well before day 10 

12Z EPS actually backed off a little more on the wet weather later in the run... and the control run was fairly dry.    Also interesting to note that the cold shot in the middle of next week trended stronger on the ECMWF, EPS, and the control run.  

[TT-SEA]

8 minutes ago, MWG said:

Oof

I hope we do get more rain! February looked so bad. Looking at this 2013 was a bad year and I remember that was the first year I experienced with smoke in the valley for days. 

2013 was very dry up here as well.     But 2019 was the driest year in the last decade... despite having the wettest summer.  

[Deweydog]

1 hour ago, Front Ranger said:

Yep. Tim likes to make a big deal of wet years, but usually those are due to unusual wetness in the fall/winter, when people expect it to be wet anyway.

Exactly. It was kinda like late last June during the heatwave. Yeah, it was 116 degrees outside, but that occurred at like 4:30 p.m. when people expect to be hot anyway.

[TT-SEA]

Quite a distinct low moving ashore on the WA coast this afternoon... the spin is very apparent on the satellite and the radar.    

[Cascadia_Wx]

12z EPS

[Deweydog]

20 years ago right now it was coming.