October 2024 PNW Weather Discussion

[SilverFallsAndrew]

Just now, Phil said:

Very unlikely to be a dud winter in the PNW with Niña/+QBO. Even with high solar. Don’t even need stratospheric help or -NAO assist unless the PV is nuclear strong like 1975/76.

NPAC/Aleutian High can amplify enough on its own under niña/+QBO. If we had -QBO instead, the dud risk would definitely be elevated. But that’s not the case this winter.

Though there is always the rare exception. Only oddball since WWII is 1999/00 with its weird IPWP/off-equator regime that diverged significantly from niña climo.

What are your analogs homie.

[BLI snowman]

Just now, ShawniganLake said:

99/00 was ugly. But 75/76 was a pretty solid winter for Southern Vancouver island.   We can do a lot worse

75-76 had a troughy beginning and a troughy ending but the midwinter period was pretty zonal and gross.

That whole mid 70s Nina was tragic here. Plenty of troughing and a huge backdoor airmass in January 1974, but the details never quite worked out for significant snow. We went from December 1972 to November 1977 without a significant snowfall here (4"+). One of our longer droughts on record. 

[TT-SEA]

Even warmer... crash has to be coming soon but nicer than I expected today.

[Phishy Wx]

1 minute ago, TT-SEA said:

Even warmer... crash has to be coming soon but nicer than I expected today.

at least 2 weeks out

[ShawniganLake]

1 minute ago, BLI snowman said:

75-76 had a troughy beginning and a troughy ending but the midwinter period was pretty zonal and gross.

That whole mid 70s Nina was tragic here. Plenty of troughing and a huge backdoor airmass in January 1974, but the details never quite worked out for significant snow. We went from December 1972 to November 1977 without a significant snowfall here (4"+). One of our longer droughts on record. 

Yuck . Lots of marginal airmass snow events further north.  But that sounds pretty tragic to the south.  
 

We have been on such a good run lately that it almost has to end with a crap winter or two soon. Maybe not this year but probably soon.  

[TT-SEA]

4 minutes ago, Phishy Wx said:

at least 2 weeks out

Literally 2 hours out right now as cold front moves in.

[T-Town]

5 minutes ago, TT-SEA said:

Literally 2 hours out right now as cold front moves in.

So cold and windy on the deck by happy hour?  

[Phishy Wx]

6 minutes ago, TT-SEA said:

Literally 2 hours out right now as cold front moves in.

I was talking a long term 'crash' that'll be temporary 

[snow drift]

1 hour ago, Phishy Wx said:

I'm trying to find a Sept warmer than this in Spokane.  There might be one but I haven't found it yet.  Large period of record though

1938 is the only one with a warmer mean temperature.

[BLI snowman]

11 minutes ago, ShawniganLake said:

Yuck . Lots of marginal airmass snow events further north.  But that sounds pretty tragic to the south.  
 

We have been on such a good run lately that it almost has to end with a crap winter or two soon. Maybe not this year but probably soon.  

2025-26 may go the way of 1925-26. Would make sense. 

[snow drift]

Well, we aren't following 2016. This month is looking more like 2022 or 1988. Spokane may have a white election day. We'll see.

[snow drift]

[Phishy Wx]

2 minutes ago, snow drift said:

Well, we aren't following 2016. This month is looking more like 2022 or 1988. Spokane may have a white election day. We'll see.

22 had a warm Sept, 88 did not

[snow drift]

26 minutes ago, BLI snowman said:

75-76 had a troughy beginning and a troughy ending but the midwinter period was pretty zonal and gross.

That whole mid 70s Nina was tragic here. Plenty of troughing and a huge backdoor airmass in January 1974, but the details never quite worked out for significant snow. We went from December 1972 to November 1977 without a significant snowfall here (4"+). One of our longer droughts on record. 

75-76 was kind of a dud. 

[snow drift]

3 minutes ago, Phishy Wx said:

22 had a warm Sept, 88 did not

I'm saying October. 1988 had early September heat with a much colder period mid month. October 2022 and 1988 were similar.

[Phil]

This is so cool.

 

[Phil]

48 minutes ago, SilverFallsAndrew said:

What are your analogs homie.

Haven’t had time for a detailed analysis but am preliminarily blending 1970/71, 1973/74, 1988/89, 2010/11, and 2020/21, while double-weighting 1988/89 and 2010/11 because they feature the best homogeneity w/rt 2024’s low frequency state.

NOTE: This is *only* a low frequency analysis. I am aware these years had various/different patterns on weekly/monthly timescales. Unfortunately subseasonal patterns don’t offer predictive value on seasonal timescales, especially during seasonal transitions.

[SilverFallsAndrew]

Just now, Phil said:

Haven’t had time for a detailed analysis but am preliminarily blending 1970/71, 1973/74, 1988/89, 2010/11, and 2020/21, while double-weighting 1988/89 and 2010/11 because they feature the best homogeneity w/rt 2024’s low frequency state.

All of those were pretty good regionally except for 2020-21, though that one did pull off a very nice event in February. 

[iFred]

33 minutes ago, ShawniganLake said:

Yuck . Lots of marginal airmass snow events further north.  But that sounds pretty tragic to the south.  
 

We have been on such a good run lately that it almost has to end with a crap winter or two soon. Maybe not this year but probably soon.  

Probably looking at a 3-5 year window with climate change erasing most marginal events.

Id wager that the Seattle metro area goes without a WSW, we don’t see more than three days below freezing with more than three inches on the ground, or a High Wind Watch, all over the next two years.

Sure, a Nina typically portends some regional action, long range forecasts across multiple models have painted a favorable DJF, and our anthropogenically impacted upper atmosphere supports more frequent shots of continentally influenced air masses, but you can only role the dice so many times to get low land snow.

[SilverFallsAndrew]

Looks like Silver Falls scored a low of 33 last Thursday the 26th @snow_wizard. 

[AlTahoe]

5 minutes ago, Phil said:

Haven’t had time for a detailed analysis but am preliminarily blending 1970/71, 1973/74, 1988/89, 2010/11, and 2020/21, while double-weighting 1988/89 and 2010/11 because they feature the best homogeneity w/rt 2024’s low frequency state.

A 2010-2011 type winter would be wild after our 2022-2023 winter. 2010-2011 had 310" of snow at lake level and 2022-2023 had 321"

I think most people in town would not like a repeat so soon. 

[iFred]

Anyone else with citrus or sensitive fruit trees that they are caring for over winter? I know my lime won’t like 35° and can see damage from a hard frost, but my fig trees should be good to 12 hours of 25° and fared well out doors over the past year.

[SilverFallsAndrew]

November 4-5, 1973 was likely a major snow event up here... Tim would have lost his mind during November-January 73-74' as about 62" of rain fell here during that span. 

[Phil]

7 minutes ago, AlTahoe said:

A 2010-2011 type winter would be wild after our 2022-2023 winter. 2010-2011 had 310" of snow at lake level and 2022-2023 had 321"

I think most people in town would not like a repeat so soon. 

Yeah, I had second thoughts about double weighting 2010/11 because of the dissolution of the seasonal signal in the SW US w/rt the analog pool. Other factors point to a very dry SW US winter, projecting canonically.

2010/11 went wild with early season blocking and the z-cell structure improved markedly by the time the -NAM had run its course. Cannot be certain that will happen again, can only project from the low-frequency state at this time of year.

If 2024/25 is destined to take a turn like 2010/11, we’ll likely begin seeing early indicators of it in roughly 5-7 weeks.

[MossMan]

52 minutes ago, TT-SEA said:

Even warmer... crash has to be coming soon but nicer than I expected today.

It’s 58 and cloudy here. 

[AlTahoe]

5 minutes ago, Phil said:

Yeah, I had second thoughts about double weighting 2010/11 because other factors point to a very dry SW US winter.

2010/11 went wild with early season blocking and the z-cell structure improved markedly by the time the -NAM had run its course. Cannot be certain that will happen again, can only project from the low-frequency state at this time of year.

If 2024/25 is destined to take a turn like 2010/11, we’ll begin seeing early indicators of it in roughly 5-7 weeks. 

From down here 1988-1989 looks like the best fit currently. 

[SilverFallsAndrew]

Looking at Phil's analogs I see a very strong signal for a wet November, a warm December, and a cold February. 

[ShawniganLake]

13 minutes ago, iFred said:

Anyone else with citrus or sensitive fruit trees that they are caring for over winter? I know my lime won’t like 35° and can see damage from a hard frost, but my fig trees should be good to 12 hours of 25° and fared well out doors over the past year.

I’m thinking you’re joking, but fig trees thrive in our climate.  I have many customers with large fig trees that produce huge crops.  No winter protection is needed on those around here.  Perhaps the exception would be a small potted tree. 

[Phil]

I’ve seen the sun 1 time in the last 10 days. And it was for 2hrs.

Worth it to finally score rain, but not gonna lie my SAD is flaring up.

[Omegaraptor]

13 minutes ago, AlTahoe said:

From down here 1988-1989 looks like the best fit currently. 

Feb 1989 produced a -43°F reading at Boca. Pretty sure that’s the CA state cold record for February.

[T-Town]

31 minutes ago, iFred said:

Anyone else with citrus or sensitive fruit trees that they are caring for over winter? I know my lime won’t like 35° and can see damage from a hard frost, but my fig trees should be good to 12 hours of 25° and fared well out doors over the past year.

I have to bring my spider monkeys inside when it gets below 40 degrees. Kind of a pain but they’re cute and playful and so it’s well worth it. They would love your fig and lime trees.  

[AlTahoe]

8 minutes ago, Omegaraptor said:

Feb 1989 produced a -43°F reading at Boca. Pretty sure that’s the CA state cold record for February.

yep and -29F in South Lake which tied the record. I like 1988-1989 as an analog for this winter but the February cold snap was kind of a one off with a record setting SSW. 

[MossMan]

Puffy. 

[Deweydog]

6 minutes ago, MossMan said:

Puffy. 

Nice little diddy.

[ShawniganLake]

Still just 54 here but I think the rain is finished.  

[SilverFallsAndrew]

78 without a cloud in the sky in Albany 

[iFred]

1 hour ago, T-Town said:

I have to bring my spider monkeys inside when it gets below 40 degrees. Kind of a pain but they’re cute and playful and so it’s well worth it. They would love your fig and lime trees.  

Yeah, we'll have a couple dozen nights below 40º this year. Should be out of the proverbial fruit woods by mid Jan. Not joking about all of this either, we are due for a few years in a row with limited cool season action and it isn't worth getting worked up over a CFS forecast or some long range that is going to yield 43º and cold rain, which wont hurt my plants.

My family is looking at doing a custom built house in 3-4 years, and I want to get an orangery built, so that should be just in time for our statistical once-a-decade regional event. If the forum is still focused on the weather around then, we can all look back at this post and reminisce about the time that I went from being a cold and snow lover to a full grown adult.

[RentonHill]

1 hour ago, Phil said:

Yeah, I had second thoughts about double weighting 2010/11 because of the dissolution of the seasonal signal in the SW US w/rt the analog pool. Other factors point to a very dry SW US winter, projecting canonically.

2010/11 went wild with early season blocking and the z-cell structure improved markedly by the time the -NAM had run its course. Cannot be certain that will happen again, can only project from the low-frequency state at this time of year.

If 2024/25 is destined to take a turn like 2010/11, we’ll likely begin seeing early indicators of it in roughly 5-7 weeks.

thoughts on the PV that keeps dragging its feet getting going? 

[snow_wizard]

2 hours ago, BLI snowman said:

75-76 had a troughy beginning and a troughy ending but the midwinter period was pretty zonal and gross.

That whole mid 70s Nina was tragic here. Plenty of troughing and a huge backdoor airmass in January 1974, but the details never quite worked out for significant snow. We went from December 1972 to November 1977 without a significant snowfall here (4"+). One of our longer droughts on record. 

Seattle had the lucky AR which turned to snow event in December 1974.  I still remember that one.

[Deweydog]

Gorgeous day. Has that dug-in stolen feel to it.

Two months…