Current & Forecast Climate Drivers

Locke

One of Us
Jul 5, 2019
184
1,047
263
Brisbane
oceanicoriginals.com
Yep I was thinking about that before headed to this thread! So much coincidence. The 2002 El Nino was incredibly strong and severe despite after 3 years of La Nina. The year of 2000 was very cold especially in the winter like 2022 experiencing now.

2001 brought last hurrah of floods in early of the year before switch to dry in middle of the year that lead to El Nino conditions and positive IOD. 2001/2002 summer saw bushfires started before eased in late 2003. So definitely 2023 will be similar to 2001.
BOM classified the 2002 event as Weak to Moderate. The ONI peaked at 1.3 compared to 2.4 for the 1997/98 event and 2.6 for the 2015/16 event.

Certainly there was no significant rebound to a big El Nino after 3 consectuive years of La Nina in 1973 to 1976. It was only six years later that we got the huge El Nino in 82/83 which interestingly coincided with the El Chichon volcanic eruption that seemed to stop the global temp response you would normally see from such an El Nino event.
 
  • Like
Reactions: Flowin
Remove ads with a
Ski Pass

weathersourse

One of Us
May 24, 2022
313
961
213
If you get multi tropical systems, either tropical land lows or developed tc's traversing in your area in a given season. Don't think many would be happy with the flooding and damage to infrastructure that would bring.

If you are in a position to and are so unhappy with the climate in your region best
bet is move on to greener pastures.
 

weathersourse

One of Us
May 24, 2022
313
961
213
SSTanomL_nino3.png
 

weathersourse

One of Us
May 24, 2022
313
961
213
Screenshot_20220718_190052.jpg

Looking @ amons re : the trades no fingerprint on the sat of upwelling of the cooler water to the surface just now.


Screenshot_20220718_190219.jpg

CFS ens think there will be a noticeable finger print from the trades upwelling in August.



Screenshot_20220718_191902.jpg


Then by 2months it thinks it will be into solid cool anoms over enso region.
 
Remove ads with a
Ski Pass

Mega

One of Us
Ski Pass
Jul 3, 2019
3,812
17,499
363
gone
wkxzteq_anm.gif


Subsurface cold pool grows while the warm pool dissipates. To me it seems the atmosphere was simply not ready for the switch yet.

Unfortunately, another La Nina will put South-West USA in an extremely tough position. Lake Mead isn't far from the level at which Las Vegas will have to be evacuated.
Yep it's all interconnected. Southern and western parts of the US are suffering from the same effects we'd normally see during multiple El-Ninos. Hard not to feel for them...drought sucks, and I've no doubt that'll be us again sometime in the future once El-Nino returns. It's inevitable. I know most people around here have had enough of the rain but personally I'm just making the most of it while we've got it. Precip patterns during La-Nina below:

map-lanina-irim.jpg
 

Nature's Fury II

One of Us
Dec 25, 2021
483
3,548
213
West Brisbane
CFS is going for a significant wet signal in Aus through August. It starts along western, southern and central Aus in the first two weeks and then peaks in eastern Aus through the final two weeks of the month. Can see the neg IOD influence with the NW cloud-band and Indian Ocean infeed in the first half and then the forecast easterly trade surge in the far south-western Pacific kicking in the second half. Looks like something brewing.

 

POW Hungry

Old n' Crusty
Moderator
Ski Pass
May 28, 2000
25,612
45,055
1,063
Eastern Burbs of Sydney
CFS is going for a significant wet signal in Aus through August. It starts along western, southern and central Aus in the first two weeks and then peaks in eastern Aus through the final two weeks of the month. Can see the neg IOD influence with the NW cloud-band and Indian Ocean infeed in the first half and then the forecast easterly trade surge in the far south-western Pacific kicking in the second half. Looks like something brewing.

This is supported by RW models, I just noticed it this morning. Looks like increased likelihood of Tasman/EC troughing.
Winter ridge parked South of Tasman would be catalytically consequential for the SE seaboard.
Despite being V long range, this signal is prevalent for a week or two.
1658529118393.png
 

Dylan Kearney

One of Us
May 27, 2019
163
1,048
263
This is supported by RW models, I just noticed it this morning. Looks like increased likelihood of Tasman/EC troughing.
Winter ridge parked South of Tasman would be catalytically consequential for the SE seaboard.
Despite being V long range, this signal is prevalent for a week or two.
1658529118393.png
Loving these posts - very informative!
The RW model here display 26.08 - 30.08. Does this forecast event out for a full month? Trying to discover when these signals are appearing the most, across different models.
 

POW Hungry

Old n' Crusty
Moderator
Ski Pass
May 28, 2000
25,612
45,055
1,063
Eastern Burbs of Sydney
Loving these posts - very informative!
The RW model here display 26.08 - 30.08. Does this forecast event out for a full month? Trying to discover when these signals are appearing the most, across different models.
Be careful not to take them too literally.
By design, they're initialised from a broader range of inputs (climatic).

More here:
 
Last edited:
Remove ads with a
Ski Pass

weathersourse

One of Us
May 24, 2022
313
961
213
This is supported by RW models, I just noticed it this morning. Looks like increased likelihood of Tasman/EC troughing.
Winter ridge parked South of Tasman would be catalytically consequential for the SE seaboard.
Despite being V long range, this signal is prevalent for a week or two.
1658529118393.png
That winter ridge parked usually extends over NZ is the text book la-nina pattern for over that region during the cold phase of enso.
 
  • Like
Reactions: POW Hungry

POW Hungry

Old n' Crusty
Moderator
Ski Pass
May 28, 2000
25,612
45,055
1,063
Eastern Burbs of Sydney
Just a hunch, tend to think over the months+ we may see a like 1975/76 period analogue with rainfall for our region.

Just a hunch and maybe worth just 2 grains of salt @ this time.
...And that wouldn't be the first comparison to '76, I've heard lately:
 

weathersourse

One of Us
May 24, 2022
313
961
213
...And that wouldn't be the first comparison I've heard to '76, lately:
Humm had not see see them to be honest, i was going off a mixture enso and -neg iod analogue in our region. But yeah that's interesting to know.
 
  • Like
Reactions: POW Hungry

weathersourse

One of Us
May 24, 2022
313
961
213
Screenshot 2022-07-23 15:59:41.png








Screenshot 2022-07-23 16:07:47.png





now.
Screenshot 2022-07-23 16:44:08.png

Screenshot 2022-07-23 16:41:39.png


Just for anyone new looking in and wondering what are we talking about. Everyone has been there @ some point.





...................................................................................................................................

As others have stated can be enhanced by passing rossbywaves .
 

weathersourse

One of Us
May 24, 2022
313
961
213
MJO
Its now moved into 1 asper data.
2022 07 16 0.390 -0.373 8 0.540 215.1
2022 07 17 0.428 -0.272 8 0.508 203.8
2022 07 18 0.346 -0.145 8 0.375 151.4
2022 07 19 0.340 -0.090 8 0.352 142.4
2022 07 20 0.413 -0.040 8 0.415 168.5
2022 07 21 0.494 -0.001 8 0.494 200.7
2022 07 22 0.488 0.155 1 0.512 207.3

Most interesting thing for me over the next month is what happens with this mjo forecast.

Screenshot 2022-07-24 19:43:19.png


cfs plot has the signal in 1 atm as-well. Guess its just wait and see when it goes over the maritime what it can or cant deliver in weather.
 

POW Hungry

Old n' Crusty
Moderator
Ski Pass
May 28, 2000
25,612
45,055
1,063
Eastern Burbs of Sydney
MJO
Its now moved into 1 asper data.
2022 07 16 0.390 -0.373 8 0.540 215.1
2022 07 17 0.428 -0.272 8 0.508 203.8
2022 07 18 0.346 -0.145 8 0.375 151.4
2022 07 19 0.340 -0.090 8 0.352 142.4
2022 07 20 0.413 -0.040 8 0.415 168.5
2022 07 21 0.494 -0.001 8 0.494 200.7
2022 07 22 0.488 0.155 1 0.512 207.3

Most interesting thing for me over the next month is what happens with this mjo forecast.

Screenshot 2022-07-24 19:43:19.png


cfs plot has the signal in 1 atm as-well. Guess its just wait and see when it goes over the maritime what it can deliver in weather.
After seeing that Ensembles outlook above, recent history tells us it'll hit those Easterly trades and will get sent packing, just as it has done for the last 18 months.

But yes, worth getting the popcorn out....
 

weathersourse

One of Us
May 24, 2022
313
961
213
Indeed that will very likely happen again @6. Its that extratropical branch part of the wave cell it forecasts over our region on the 13-19th thats got my interest atm.
 
  • Like
Reactions: POW Hungry

POW Hungry

Old n' Crusty
Moderator
Ski Pass
May 28, 2000
25,612
45,055
1,063
Eastern Burbs of Sydney

POW Hungry

Old n' Crusty
Moderator
Ski Pass
May 28, 2000
25,612
45,055
1,063
Eastern Burbs of Sydney
Just a quick look @ what long range control ens with troughs in part of the period above. Won't leave it up to long but yeah some decent looking inland troughs in the mix as-well with its long range solution atm.
gfs-ensemble-extended-all-c00-aus-mslp_anom-1658620800-1659657600-1660435200-80.gif
That one peaking through NT on the 9th, looks like it’ll haul-arse and cart some solid IOD moisture (NW cloud band).
 

PeteJ

One of Us
Ski Pass
Jul 5, 2019
696
4,371
263
Toowoomba
Interesting how the pressure at Tahiti has been constantly lower for a while now and showing no sign of rising. Won’t be long until the 30 day soi is close to zero.
 

weathersourse

One of Us
May 24, 2022
313
961
213
Would not be surprised atm if the bom has their fingers on the trigger @ their end. Then maybe not, unsure what measures they use these days.




Screenshot_20220726_094855.jpg

IRI data above.

............................................................



GFS sio plotting with their data displays a still strong Nina atmosphere.

Screenshot_20220726_100348.jpg
 

Mega

One of Us
Ski Pass
Jul 3, 2019
3,812
17,499
363
gone
Interesting how the pressure at Tahiti has been constantly lower for a while now and showing no sign of rising. Won’t be long until the 30 day soi is close to zero.
They've been under the tail-end of a mid-lat trough extending from one of those big lows sweeping across underneath. However, this quickly breaks down making way for significantly higher pressures returning again from about tomorrow onwards. I'd expect to see the return of stronger SOI values again after about Wednesday provided Darwin's pressure remains relatively lower than average.
 

BlueHue

One of Us
Ski Pass
Apr 17, 2003
3,947
4,763
363
47
South of Cooma
MJO
Its now moved into 1 asper data.
2022 07 16 0.390 -0.373 8 0.540 215.1
2022 07 17 0.428 -0.272 8 0.508 203.8
2022 07 18 0.346 -0.145 8 0.375 151.4
2022 07 19 0.340 -0.090 8 0.352 142.4
2022 07 20 0.413 -0.040 8 0.415 168.5
2022 07 21 0.494 -0.001 8 0.494 200.7
2022 07 22 0.488 0.155 1 0.512 207.3

Most interesting thing for me over the next month is what happens with this mjo forecast.

Screenshot 2022-07-24 19:43:19.png


cfs plot has the signal in 1 atm as-well. Guess its just wait and see when it goes over the maritime what it can or cant deliver in weather.
Someone let AAO now that it needs to hit -2 stat.
 

weathersourse

One of Us
May 24, 2022
313
961
213
They've been under the tail-end of a mid-lat trough extending from one of those big lows sweeping across underneath. However, this quickly breaks down making way for significantly higher pressures returning again from about tomorrow onwards. I'd expect to see the return of stronger SOI values again after about Wednesday provided Darwin's pressure remains relatively lower than average.
Yeah over the years i have seen it pointed out by some senior tropical met's on a forum i use to be on a quite a few years ago now closed down. Back ground pressures and troughs can cause noise with sio values.
 
  • Like
Reactions: PeteJ and Mega

Mega

One of Us
Ski Pass
Jul 3, 2019
3,812
17,499
363
gone
I think you guys might really like this paper. It talks about the role of the meridional winds into the equatorial Pacific and in particular focuses on the historic SE'ly trade surge which occurred during March this year. I am just having a read through now. There is so much good stuff in this paper, I will try to pick apart the most interesting stuff without it becoming a giant wall of text (and I've chosen to bold some of the more key parts). Full paper here:



"ABSTRACT: Based on the updates of the Climate Prediction Center and International Research Institute for Climate and Society (CPC/IRI) and the China Multi-Model Ensemble (CMME) El Niño-Southern Oscillation (ENSO) Outlook issued in April 2022, La Niña is favored to continue through the boreal summer and fall, indicating a high possibility of a three-year La Niña (2020–23). It would be the first three-year La Niña since the 1998–2001 event, which is the only observed three-year La Niña event since 1980. By examining the status of air–sea fields over the tropical Pacific in March 2022, it can be seen that while the thermocline depths were near average, the southeasterly wind stress was at its strongest since 1980. Here, based on a quaternary linear regression model that includes various relevant air–sea variables over the equatorial Pacific in March, we argue that the historic southeasterly winds over the equatorial Pacific are favorable for the emergence of the third-year La Niña, and both the anomalous easterly and southerly wind stress components are important and contribute ~50% of the third-year La Niña growth, respectively. Additionally, the possible global climate impacts of this event are discussed."



"As seen, neither of the thermocline variables (TCDa_M and TCDa_G) are significantly abnormal this year, indicating a challenge in predicting the subsequent ENSO evolution from the ENSO recharge–discharge theory and other classical ENSO theories that emphasize the variations in thermocline depth, i.e., zonal oceanic dynamics. In contrast, the atmospheric variables exhibit appreciable anomalies, with the easterly wind stress being comparable to that of 2000 and the southerly wind stress reaching its largest amplitude since 1980."

"It can be seen that for 2000, it is the strong easterly wind stress that overcame the opposite effects from all the other three variables. It suggests that although the oceanic dynamics (characterized by the thermocline depth distribution) does not support more cooling based on the recharge oscillator and other classical ENSO theories, the abnormally strong easterly wind in the western Pacific can lead to cooling through exciting the upwelling oceanic Kelvin waves and driving the anomalous westward surface currents.

However, the situation is quite different in 2022. The anomalous easterly and southerly wind stresses are both important, and each may contribute ~50% toward the pending La Niña evolution, while the variables related to the TCD (thermocline depth) have little effect. The southerly wind is argued to be able to intensify the ocean upwelling south of the equator (Xie et al., 2018) and enhance the incursion of the subsurface cold water on the off-equator into the equatorial area (Zheng et al., 2015), thus acting as an extra cooling effect on the SST variations.

Also, as suggested in Fang and Zheng (2021), the role played by the meridional wind on the equatorial eastern Pacific is more important on the following ENSO evolution after 2000 than during 1980–99, which further explains the large difference between these two events."

"The differences between March and April 2022 (Fig. 4) clearly indicate the persistence of the current La Niña condition. More specifically, the TCD is getting shallower in the central to eastern Pacific, the southeasterly wind over the equatorial Pacific is still strong and even enhanced over the central tropical Pacific, and the SST is getting colder in the entire basin. Therefore, based on the current air–sea status and the quaternary linear regression model, our perspective is that the historic southeasterly winds over the equatorial Pacific are propitious to the emergence of a third-year La Niña event in 2022/23.
 

Storm1

Hard Yards
Feb 6, 2022
98
474
83
  • Like
Reactions: PeteJ and Vinny
Remove ads with a
Ski Pass
Remove ads with a
Ski Pass

Log in

or Log in using