2024-2025 La Nina

[GaWx]

1 hour ago, brooklynwx99 said:

if the Bomb Cyclone in Jan 2018 was closer to the coast, that would have been the widespread 24-36" event. Juno, obviously, was close as well. it's just a matter of time, really

 

1 hour ago, 40/70 Benchmark said:

The issue with the bomb cyclone is that it occluded so far to the south...not that it was too far east.

 

1 hour ago, jm1220 said:

That was a really nice one (1/4/2018), too bad it couldn’t slow down. It was hauling. 

 That one gave my area the heaviest IP/SN (2”) since 12/1989’s 3-5” and the heaviest liquid equiv of wintry precip (0.75” with 0.5” being ZR on 1/3/2018) since the predecessor to the Knickerbocker storm of 1/1922 that gave SAV the worst ZR on record.

 However, I haven’t had even a T of wintry since then. This drought of nearly 7 years of no wintry incl T is longest on record!

[bluewave]

On 9/24/2024 at 10:58 AM, bluewave said:

The most interesting part of this is the volatility of both the NAO and AO indices. We saw a record low Iceland 500mb height anomaly in August. Now this month one of the highest September daily 500mb height anomalies over Greenland near +500meters. This has been a theme in recent years with some of the greatest positive and negative swings over a relatively short period we have ever seen. 

 

On 9/24/2024 at 11:18 AM, bluewave said:

It’s interesting that this study came out in 2009 right before the next big step up in volatility over the last 10 to 15 years. We can also add the AO which overlaps with the NAO. It does seem like more of the volatility has been evident in the AO while the winter NAO seems to be becoming more positive. 

https://www.whoi.edu/press-room/news-release/study-links-swings-in-north-atlantic-oscillation-variability-to-climate-warming/

 

The research team found the variability of the NAO decade-to-decade (multi-decadal scale) has been larger, swinging more wildly, during the late twentieth century than in the early 1800s, suggesting that variability is linked to the mean temperature of the Northern Hemisphere. This confirms variability previously reported in past terrestrial reconstructions.

“When the Industrial Revolution begins and atmospheric temperature becomes warmer, the NAO takes on a much stronger pattern in longer-term behavior,” said Goodkin. “That was suspected before in the instrumental records, but this is the first time it has been documented in records from both the ocean and the atmosphere.”

The North Atlantic Oscillation is described by the NAO index, calculated as a weighted difference between the polar low and the subtropical high during the winter season. In a positive phase, both the low-pressure zone over Iceland and high pressure over the Azores are intensified, resulting in changes in the strength, incidence, and pathway of winter storms crossing the Atlantic. In a negative phase, a weak subtropical high and a weak Icelandic low results in fewer and weaker winter storms crossing on a more west-east pathway.

The NAO index varies from year to year, but also exhibits a tendency to remain in one phase for intervals lasting more than a decade. An unusually long period of positive phase between 1970-2000 led to the suggestion that global warming was affecting the behavior of the NAO.

“Anthropogenic (human-related) warming does not appear to be altering whether the NAO is in a positive or negative phase at multi-decadal time scales,” said WHOI paleoclimatologist Konrad Hughen. “It does seem to be increasing variability. Clearly, this has implications for the future.”

“As temperatures get warmer, there’s potential for more violent swings of the NAO — the phases becoming even more positive and even more negative,” Hughen added. “If the NAO locks more into these patterns, intense storms will become more intense and droughts will become more severe.”

 

 

[BlizzardWx]

49 minutes ago, GaWx said:

That one gave my area the heaviest IP/SN (2”) since 12/1989’s 3-5” and the heaviest liquid equiv of wintry precip (0.75” with 0.5” being ZR on 1/3/2018) since the predecessor to the Knickerbocker storm of 1/1922 that gave SAV the worst ZR on record.

 However, I haven’t had even a T of wintry since then. This drought of nearly 7 years of no wintry incl T is longest on record!

Down here we've done a little better, but it's still been pretty bad. Since 15-16 the seasonal totals have been:

Long term mean of 8.7"
15-16: 3.0"
16-17: 0.7"
17-18: 2.1"
18-19: 2.9"
19-20: 3.1"
20-21: 15.8"
21-22: 12.0"
22-23: 2.0"
23-24: 1.6"

That's 5/7 with less than 50% of normal. The 43.4/78.3 inches over that stretch is about 55% of normal snow. I was in Phoenix for 2019-2022 and then in Tulsa the last two years. So I've only seen about 3.5" of snow in 5 years. There have been a few sleet and zr events in there but we all know snow is where its at! The patterns that help me to do well aren't exactly the same as most in this sub but they are at least related. 

 

[GaWx]

Just now, bluewave said:

 

 

 

1. Per NOAA monthlies, Aug 2024 didn’t have anywhere near record +PNA for Aug as it was only +0.63. Since 1950, 18 Augs had a stronger +NAO incl way higher in ‘22 and ‘18:

https://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/norm.nao.monthly.b5001.current.ascii.table
 

2. Per NOAA’s NAO table 2024’s drop Aug to Sep was still big but not as big as 1976, 1983, and 2022.

 

[michsnowfreak]

2 hours ago, FPizz said:

Our area is boom/bust most of the time anyway.  Only 7 times in the past 37 years that I've been measuring have I gotten to within 25% +/- our average.  It is usually well below or above average. 

That was always my impression of the east coast. Completely different that the Great Lakes. 

[bluewave]

9 minutes ago, GaWx said:

1. Per NOAA monthlies, Aug 2024 didn’t have anywhere near record +PNA for Aug as it was only +0.63. Since 1950, 18 Augs had a stronger +NAO incl way higher in ‘22 and ‘18:

https://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/norm.nao.monthly.b5001.current.ascii.table
 

2. Per NOAA’s NAO table 2024’s drop Aug to Sep was still big but not as big as 1976, 1983, and 2022.

 

The way they calculate their numbers doesn’t really do justice to the magnitude of the pressure swing from August to September at the surface to 500mb.

[40/70 Benchmark]

3 hours ago, bluewave said:

The patterns becoming more persistent are the result of the warming atmosphere and oceans. So observing these changes and incorporating them into forecast techniques is just pattern recognition. I take a very data driven approach so it’s more pattern persistence than persistence forecasting.

Right...until the pattern stops persisting. Nobody has it all figured out.

[Typhoon Tip]

research is nearing the codification of a new enso mode ...  'la neutered'   ...it's basically huge negative/positive departures, while the wholesale surrounding global medium behaves like which ever it is, it's completely ballless to motivate any response at all 

[bluewave]

On 10/2/2024 at 2:59 PM, michsnowfreak said:

I was referring to individual decades, not intra-decade stretches.

The current 9 year winter average at DET is 31.1°or +1.6° warmer than the previous peak in 1957 which was 29.5°. NYC is at 38.5° or +2.1 above the previous peak of 36.4° set back in 2002. The effects of this record warm winter run since 15-16 are more pronounced closer to the East Coast. 

[so_whats_happening]

12 hours ago, donsutherland1 said:

That's probably because of Helene's impact on NCEI's Asheville center.

Yep was reading about the other day. PSL products are also being affected. Hope they can get everything situated relatively quick.

[so_whats_happening]

We are just about at what used to be the seasonal average (1950-2000) for ACE at about 90 ish. The ACE of 1991-2020 climo era is what used to be considered a hyperactive season which is now the average. Anyways we are right at average for total storm/ hurricanes/ major hurricanes for the season. It looks as though we get maybe one more named system but we should trail off the season near the time it typically does. Kirk and Leslie alone should be able to pick up enough ACE to put us right near the 1991-2020 climo ACE.

As for other areas the strong WWB event in the Indian Ocean looks to spark a cyclone for that region and maybe 1 more solid typhoon in the WPAC before things globally calm down a bit. Most models still have what looks like a solid 5/6 pass for the MJO coming up around mid month. We should also start to see the -NAO relax quite a bit going forward as well but that western ridge may mean business again as we get to mid month. Here is a look at what the pattern could entail based off an MJO Nina passage through 5/6. I started using the Nina base instead of La Nada as we are right on the edge of La Nina status versus over the summer where were virtually neutral. Nothing too exciting on the horizon which is probably for the best after Helene, most could use a solid dry period.

Im excited to get some nice diurnal swings and maybe get a solid kick start into leaf changing season. Ill update some of the Oceanic components sometime next week.

[snowman19]

41 minutes ago, so_whats_happening said:

We are just about at what used to be the seasonal average (1950-2000) for ACE at about 90 ish. The ACE of 1991-2020 climo era is what used to be considered a hyperactive season which is now the average. Anyways we are right at average for total storm/ hurricanes/ major hurricanes for the season. It looks as though we get maybe one more named system but we should trail off the season near the time it typically does. Kirk and Leslie alone should be able to pick up enough ACE to put us right near the 1991-2020 climo ACE.
As for other areas the strong WWB event in the Indian Ocean looks to spark a cyclone for that region and maybe 1 more solid typhoon in the WPAC before things globally calm down a bit. Most models still have what looks like a solid 5/6 pass for the MJO coming up around mid month. We should also start to see the -NAO relax quite a bit going forward as well but that western ridge may mean business again as we get to mid month. Here is a look at what the pattern could entail based off an MJO Nina passage through 5/6. I started using the Nina base instead of La Nada as we are right on the edge of La Nina status versus over the summer where were virtually neutral. Nothing too exciting on the horizon which is probably for the best after Helene, most could use a solid dry period.
Im excited to get some nice diurnal swings and maybe get a solid kick start into leaf changing season. Ill update some of the Oceanic components sometime next week.

Looks like another Atlantic TC shutdown is coming. I also think the huge solar spike we are seeing right now is contributing to this as well. IMO, 100-110 ACE is where we finish this tropical season

 

 

 

 

Hopefully we see OISST update again soon. Been happy to at least see the TAO, CRW and the QBO data still coming in

 

 

 

 

 

 

[so_whats_happening]

Just now, snowman19 said:

Looks like another Atlantic TC shutdown is coming. I also think the huge solar spike we are seeing right now is contributing to this as well. IMO, 100-110 ACE is where we finish this tropical season

 

 

 

Hopefully we see OISST update again soon. Been happy to at least see the TAO, CRW and the QBO data still coming in

 

 

Maybe for the bolded but this is about when we typically start to see the seasonal change enough to end the season. Still could be a random storm that pops up in the Caribbean but nothing on the horizon as we go toward mid month and further.

I like to think solar does still have some important impacts into patterns but I think of it as a bit of a lagged component in that this spike will show up later on in our sensible weather.

[bluewave]

19 hours ago, 40/70 Benchmark said:

Agree completely.

However, I thinkl the difficulty getting to within 25% of average is more applicable the further south one is.....that is not difficult in the north.

At least in the first 5 winters of the 2020s, the snowfall deficits from Boston down to DC are pretty equally distributed from north to south relative to their past 5 year lowest levels. The snowfall deficit is only half of the equation. As even though NYC wasn’t able to surpass their lowest 5 year runs like Boston, Philly, and DC did this last winter, the lean 5 year periods from the past were much colder. So this adds to why people are saying it hasn’t really felt much like winter during the 2020s so far except for some good periods briefly in Jan 22 and during 21-22. Let’s hope we can stage some type of snowfall comeback during the 2nd half of the decade so we can avoid going from the snowiest decade in the 2010s to least snowiest decade in the 2020s. 
 

Lowest 5 year snowfall averages at Boston, Philly, and DC with NYC in 2nd place

BOS…..19-20 to 23-24….26.1”….past record 50-51 to 54-55….28.0”

NYC…..19-20 to 23-24….14.2”….past record 27-28 to 31-32….11.8”

PHI…….19-20 to 23-24…..9.7”….past record 48-49 to 52-53…11.8”

DCA…..19-20 to 23-24…..5.5”….past record 97-98…to 01-02…7.5”

[40/70 Benchmark]

14 hours ago, Typhoon Tip said:

research is nearing the codification of a new enso mode ...  'la neutered'   ...it's basically huge negative/positive departures, while the wholesale surrounding global medium behaves like which ever it is, it's completely ballless to motivate any response at all 

I am of the opinion that this season will behave in a manner that is consistent with La Nina, however, La Nina will not be the primary driver...if that makes sense.

[40/70 Benchmark]

1 hour ago, bluewave said:

At least in the first 5 winters of the 2020s, the snowfall deficits from Boston down to DC are pretty equally distributed from north to south relative to their past 5 year lowest levels. The snowfall deficit is only half of the equation. As even though NYC wasn’t able to surpass their lowest 5 year runs like Boston, Philly, and DC did this last winter, the lean 5 year periods from the past were much colder. So this adds to why people are saying it hasn’t really felt much like winter during the 2020s so far except for some good periods briefly in Jan 22 and during 21-22. Let’s hope we can stage some type of snowfall comeback during the 2nd half of the decade so we can avoid going from the snowiest decade in the 2010s to least snowiest decade in the 2020s. 
 

Lowest 5 year snowfall averages at Boston, Philly, and DC with NYC in 2nd place

BOS…..19-20 to 23-24….26.1”….past record 50-51 to 54-55….28.0”

NYC…..19-20 to 23-24….14.2”….past record 27-28 to 31-32….11.8”

PHI…….19-20 to 23-24…..9.7”….past record 48-49 to 52-53…11.8”

DCA…..19-20 to 23-24…..5.5”….past record 97-98…to 01-02…7.5”

I mean north of Boston. 

[PhiEaglesfan712]

20 hours ago, brooklynwx99 said:

if the Bomb Cyclone in Jan 2018 was closer to the coast, that would have been the widespread 24-36" event. Juno, obviously, was close as well. it's just a matter of time, really

ACY still got over a foot with that one. The January 28-29, 2022 snow map is eerily similar. Both were misses north and west of PHL, but the coast really got slammed.

The last widespread 24-36" event was January 22-23, 2016.

[40/70 Benchmark]

34 minutes ago, PhiEaglesfan712 said:

ACY still got over a foot with that one. The January 28-29, 2022 snow map is eerily similar. Both were misses north and west of PHL, but the coast really got slammed.

The last widespread 24-36" event was January 22-23, 2016.

Yea, that event was better south of New England because H5 closed off so early and far to the south...it was an occluded, shredded mess when it got up here...amounts much over 12" were scarce.

[40/70 Benchmark]

I think it closed off at like the latitude of Virginia...

[snowman19]

EPS is developing a massive GOA vortex around mid-month. Fits MJO 4-5, October, -ENSO composites

[George001]

2 hours ago, 40/70 Benchmark said:

I think it closed off at like the latitude of Virginia...

That was a great storm for my area still, but definitely left some on the table because of this. Most of the truly high end events are miller bs for a reason, I would rather have the low bombing out right under us than way south. Regardless, 14-15 inches is still a really good storm, I would gladly take another event like that after the past 2 years.

[George001]

One thing I am interested in is the prospect of more miller bs this winter. With the active northern branch combined with the very warm SSTs off the coast I think we will see some big storms. The big question is the temp profile, seasonal guidance right now has a very Nina like BN north AN south like 2022-2023, but guidance does have the cold bleeding somewhat farther south than that year. Still too early to really mean much, but it’s worth watching if that holds up by November.

[snowman19]

Subsurface cold continuing to build, models are getting stronger with the EWB in region 3.4. Fits with the MJO propagating to the Maritime Continent 

TIWs showing up in 3.4

[bluewave]

3 hours ago, PhiEaglesfan712 said:

ACY still got over a foot with that one. The January 28-29, 2022 snow map is eerily similar. Both were misses north and west of PHL, but the coast really got slammed.

The last widespread 24-36" event was January 22-23, 2016.

January 2022 was the last month for parts of the region that could be considered a great winter month.

 

Monthly Total Snowfall for Atlantic City Area, NJ (ThreadEx)
Click column heading to sort ascending, click again to sort descending.

Mean	0.0	T	0.1	8.0	1.6	T	0.0	9.7
2019-2020	0.0	T	0.5	T	T	0.0	0.0	0.5
2020-2021	0.0	0.0	T	1.0	6.3	0.0	0.0	7.3
2021-2022	0.0	T	T	33.2	0.1	T	0.0	33.3
2022-2023	0.0	0.0	T	T	0.3	T	0.0	0.3
2023-2024	0.0	0.0	T	5.9	1.4	T	0.0	7.3

[40/70 Benchmark]

2 hours ago, snowman19 said:

EPS is developing a massive GOA vortex around mid-month. Fits MJO 4-5, October, -ENSO composites

I hope it gets uber-strong this month.

[donsutherland1]

13 hours ago, so_whats_happening said:

Yep was reading about the other day. PSL products are also being affected. Hope they can get everything situated relatively quick.

I agree. A wide range of data products has been disrupted.

[George001]

9 minutes ago, snowman19 said:

Subsurface cold continuing to build, models are getting stronger with the EWB in region 3.4. Fits with the MJO propagating to the Maritime Continent 

TIWs showing up in 3.4

Looks like things are on track for an official La Niña by ONI (likely high end weak). The development of this Nina has been impressive over the past few weeks.

[snowman19]

4 hours ago, 40/70 Benchmark said:

I am of the opinion that this season will behave in a manner that is consistent with La Nina, however, La Nina will not be the primary driver...if that makes sense.

As far as a typical Niña/-PDO/+QBO/solar max response, yes I agree 

[michsnowfreak]

20 hours ago, bluewave said:

The current 9 year winter average at DET is 31.1°or +1.6° warmer than the previous peak in 1957 which was 29.5°. NYC is at 38.5° or +2.1 above the previous peak of 36.4° set back in 2002. The effects of this record warm winter run since 15-16 are more pronounced closer to the East Coast. 

Again, Im aware. Never said it wasnt a warm stretch. I merely said I was going by decade to decade, not intra-decade stretches.

It really has been 5 very mild winters here...the other 4 were basically close to normal (2017-18 was colder than avg). A very interesting fact - during this 9 year warm stretch, avg snowfall at Detroit was 40.1". Thats only 5" below the modern day avg, and basically exactly avg for the 20th century. # of annual 1"+ snowcover days, however, averaged 40 during this stretch, which is 10 days below both the modern & longterm avg. (the prior 8 years, which would be 2007-08 thru 2014-15, averaged 58.3" & 61 days of 1"+ snowcover, both well above avg.

Without diving into anymore stats, basically I have come to the conclusion that the increase in precip is an absolute positive for our winter climate. Warmer winters are yielding more snow than they used to (snowcover suffers far more than snowfall), and avg to colder than avg winters also yield more snow. (Of course this is all "on average", there will be low years). Even the warmest winters can yield respectable snowfall amounts IF the patterns are right. This is why I do not focus as much on temps as you guys do, I am more worried about avoiding the real torch winters like 2023-24, but winter at +2F can be as good or better than a winter of -2F when it comes down to snow. (Of course, I personally always root on cold lol).

[bluewave]

2 hours ago, michsnowfreak said:

Again, Im aware. Never said it wasnt a warm stretch. I merely said I was going by decade to decade, not intra-decade stretches.

It really has been 5 very mild winters here...the other 4 were basically close to normal (2017-18 was colder than avg). A very interesting fact - during this 9 year warm stretch, avg snowfall at Detroit was 40.1". Thats only 5" below the modern day avg, and basically exactly avg for the 20th century. # of annual 1"+ snowcover days, however, averaged 40 during this stretch, which is 10 days below both the modern & longterm avg. (the prior 8 years, which would be 2007-08 thru 2014-15, averaged 58.3" & 61 days of 1"+ snowcover, both well above avg.

Without diving into anymore stats, basically I have come to the conclusion that the increase in precip is an absolute positive for our winter climate. Warmer winters are yielding more snow than they used to (snowcover suffers far more than snowfall), and avg to colder than avg winters also yield more snow. (Of course this is all "on average", there will be low years). Even the warmest winters can yield respectable snowfall amounts IF the patterns are right. This is why I do not focus as much on temps as you guys do, I am more worried about avoiding the real torch winters like 2023-24, but winter at +2F can be as good or better than a winter of -2F when it comes down to snow. (Of course, I personally always root on cold lol).

Yeah, you guys will manage to hold onto traditional winters longer than the I-95 coastal crew on this forum. Being closer to the center of the continent and away from the rapidly warming Atlantic are a real plus for you. The posters especially near the LES zones have been benefitting from the warmer lakes staying open longer. Even during the warmest winter in 23-24 for Marquette at +8.4, it was still 25.2°. While not great by local standards, the 126.5” of snow for Marquette in a place like NYC would wildly exceed anything in the modern record. This past warmest winter for Marquette was about the same temperature as the coldest on record for NYC in 1917-1918 at 25.7°. If NYC should ever run a +8 departure in this much warmer climate, than something close to a snowfall shutout could occur with potentially only a T to 1” for the whole season.