2024-2025 La Nina

[PhiEaglesfan712]

4 minutes ago, bluewave said:

While I don’t know whether it will be correct or not with the more poleward extension of the Aleutian Ridge than the Euro, we did have a pattern like this in 16-17. Very weak La Niña following the super El Niño in 15-16. Not sure if the CANSIPS may be underestimating the trough out West compared to 16-17 if that poleward extension verified.  While it was a mild winter in the East, that poleward extension got us in the game for a better snowfall outcome than the last few seasons. But we have a much stronger -PDO pattern now so not sure if we could do as well in the snowfall department as we did that season. Any improvement in snowfall over the last two seasons would be nice to see. 
 

Assuming a central based la nina, I have 2016-17 as the 3rd analog, after 2007-08 and 1998-99. Here at PHL, it was a blend of both. The winter of 2016-17 was closer to 1998-99, in that it featured a very warm and non-snowy February and a cooler and snowy March, with some snow during the first half of January. Late spring and summer 2017 was closer to 2008, featuring a cool May, warm June and July, and cool August.

[michsnowfreak]

57 minutes ago, 40/70 Benchmark said:

I think that is a decent analog.

2007-08 was a fantastic winter snow-wise. Extremely, extremely active in the Great Lakes region from Dec-Mar.

[snowman19]

21 minutes ago, PhiEaglesfan712 said:

Assuming a central based la nina, I have 2016-17 as the 3rd analog, after 2007-08 and 1998-99. Here at PHL, it was a blend of both. The winter of 2016-17 was closer to 1998-99, in that it featured a very warm and non-snowy February and a cooler and snowy March, with some snow during the first half of January. Late spring and summer 2017 was closer to 2008, featuring a cool May, warm June and July, and cool August.

Those analogs are way better than some of the ones getting hyped on Twitter right now (83-84, 95-96, 10-11, 13-14, 17-18 and 20-21). All one has to do is check the ENSO state and you know the exact analogs certain people are going to pick before it even happens. Just like when there’s an El Niño, you know 57-58, 65-66, 76-77, 77-78, 02-03, 09-10 and 14-15 are coming. Literally every time without fail….

[PhiEaglesfan712]

1 minute ago, snowman19 said:

Those analogs are way better than some of the ones getting hyped on Twitter right now (83-84, 95-96, 10-11, 13-14, 17-18 and 20-21). All one has to do is check the ENSO state and you know the exact analogs certain people are going to pick before it even happens. Just like when there’s an El Niño, you know 57-58, 65-66, 76-77, 77-78, 02-03, 09-10 and 14-15 are coming. Literally every time without fail….

Off the bat, we can remove 83-84 and 95-96 (we don't have a +PDO) and 13-14 (that was a multi-year ENSO neutral state, and we're coming off a strong el nino). I'll keep 10-11 and 20-21 as outside chances, and only if this remains a central based la nina. Both are first year la ninas, and 10-11 is coming off a similar ENSO state as this year (strong el nino). If this year is an east-based la nina, then 10-11 and 20-21 can be thrown in the trash.

Of course, if this becomes an east based la nina, then 17-18 becomes a good analog, as does 21-22.

[GaWx]

1 hour ago, bluewave said:

While I don’t know whether it will be correct or not with the more poleward extension of the Aleutian Ridge into Alaska than the Euro, we did have a pattern like this in 16-17. Very weak La Niña following the super El Niño in 15-16. Not sure if the CANSIPS may be underestimating the trough out West compared to 16-17 if that poleward extension verified.  While it was a mild winter in the East, that poleward extension got us in the game for a better snowfall outcome than the last few seasons. But we have a much stronger -PDO pattern now so not sure if we could do as well in the snowfall department as we did that season. Any improvement in snowfall over the last two seasons would be nice to see. 
 

Aleutian ridge is as you know the opposite of what correlates best to a cold winter in SE US, an Aleutian low. Last year many of us E US folks in the El Niño thread were so excited about all of the forecasts for a mean of a solid Aleutian low. A significantly warmer and drier winter is most likely on the way down here vs last winter’s NN to slightly AN. But winter is still my favorite season! And regardless, there are almost always a few cold snaps.

[snowman19]

14 minutes ago, PhiEaglesfan712 said:

Off the bat, we can remove 83-84 and 95-96 (we don't have a +PDO) and 13-14 (that was a multi-year ENSO neutral state, and we're coming off a strong el nino). I'll keep 10-11 and 20-21 as outside chances, and only if this remains a central based la nina. Both are first year la ninas, and 10-11 is coming off a similar ENSO state as this year (strong el nino). If this year is an east-based la nina, then 10-11 and 20-21 can be thrown in the trash.

Of course, if this becomes an east based la nina, then 17-18 becomes a good analog, as does 21-22.

Solar and geomag don’t even remotely resemble 10-11, like not even close. Solar/geomag do not match 20-21 either. No models are or have been showing an east-based Niña, so no go on 17-18 and now there is a big question in my mind as to whether we even see an official La Niña 

[GaWx]

3 hours ago, snowman19 said:

Weather is always humbling. If this does in fact turn into a cold-neutral/La Nada, it definitely humbled me as I thought a weak La Niña was the very likely outcome just a few weeks ago. Is it AGW related? Quite possibly. The other humbling phenomenon may well be the Atlantic tropical season…..

 

 

 

 

 

 

 

 

 Even if ONI doesn’t get down into weak Niña, RONI almost certainly will be hanging around that area as it already is likely in the -0.6 to -0.7 area and the SOI has turned to solid + recently. RONI could still get down to moderate Niña. MEI also should be Niña if we can keep the SOI +.

 GEFS is forecasting strong trade winds/solid MJO MC as I assume you know. All of this should support nice cooling in 3.4.

[bluewave]

33 minutes ago, GaWx said:

Aleutian ridge is as you know the opposite of what correlates best to a cold winter in SE US, an Aleutian low. Last year many of us E US folks in the El Niño thread were so excited about all of the forecasts for a mean of a solid Aleutian low. A significantly warmer and drier winter is most likely on the way down here vs last winter’s NN to slightly AN. But winter is still my favorite season! And regardless, there are almost always a few cold snaps.

That’s why I was mentioning the influence of the WPAC warm pool from last spring into fall in the El Niño thread. The stronger Niña-like MJO phases coupled with the -PDO and weakened the Aleutian low and SE US Nino trough we typically see during El Niños. It allowed the Nino Ridge in Canada to grow stronger than usual and press down into the Mid-Atlantic. Notice how the Nino Ridge was even more expansive than the 97-98 super El Niño down into the Midwest and Mid-Atlantic. But the Aleutian low and Southeast Low response was much weaker. 
 

 

[40/70 Benchmark]

2 hours ago, snowman19 said:

Those analogs are way better than some of the ones getting hyped on Twitter right now (83-84, 95-96, 10-11, 13-14, 17-18 and 20-21). All one has to do is check the ENSO state and you know the exact analogs certain people are going to pick before it even happens. Just like when there’s an El Niño, you know 57-58, 65-66, 76-77, 77-78, 02-03, 09-10 and 14-15 are coming. Literally every time without fail….

I was guilty on some of those last year, but I think most people can see where I went astray...it certainly wasn't due to blind bias like some of these guys.

[bluewave]

2 hours ago, PhiEaglesfan712 said:

Assuming a central based la nina, I have 2016-17 as the 3rd analog, after 2007-08 and 1998-99. Here at PHL, it was a blend of both. The winter of 2016-17 was closer to 1998-99, in that it featured a very warm and non-snowy February and a cooler and snowy March, with some snow during the first half of January. Late spring and summer 2017 was closer to 2008, featuring a cool May, warm June and July, and cool August.

The difference between the 98-99 to 07-08 La Niña era and the more recent one since 16-17 is that the Aleutian Ridge and Southeast Ridge have become much stronger. 

 

[40/70 Benchmark]

39 minutes ago, bluewave said:

The difference between the 98-99 to 07-08 La Niña era and the more recent one since 16-17 is that the Aleutian Ridge and Southeast Ridge have become much stronger. 

 

Looks as though the negative anomaly in Canada is stronger, as well due to a better N PAC...so there is definitely some bad luck involved. Its a combo of shit luck and a bad pattern that has yielded dreadful returns. Maybe not so much for the mid atl, as its been more of an awful pattern for those areas...but I know up here in NE, we just have not been able to time an antecedent high well...even assuming a track west, which would turn to rain...so not even as many front enders.

[bluewave]

34 minutes ago, 40/70 Benchmark said:

Looks as though the negative anomaly in Canada is stronger, as well due to a better N PAC...so there is definitely some bad luck involved. Its a combo of shit luck and a bad pattern that has yielded dreadful returns. Maybe not so much for the mid atl, as its been more of an awful pattern for those areas...but I know up here in NE, we just have not been able to time an antecedent high well...even assuming a track west, which would turn to rain...so not even as many front enders.

Could also be that a warmer climate supports stronger 500 mb ridges. 
 

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2015GL066669

 

Apart from global scale surface warming, anthropogenic forcings also lead to warming and thermal expansion of the lower atmosphere. Here we investigate these effects using the geopotential height at 500 hPa, an indicator of the combined thermodynamic and dynamic climatic response to external forcings. We employ optimal fingerprinting, which uses information from reanalysis data sets and experiments with seven state-of-the-art climate models, to assess the role of anthropogenic and natural influences on changes in the geopotential height during the satellite era. A significant global increase in the annual and seasonal mean geopotential height due to human influence is detected, a result confirmed with four different reanalysis data sets. A more moderate increase in the annual mean associated with natural forcings is also detected. Our findings, consistent with previous detection and attribution studies of changes in temperature and sea level pressure, indicate the prominent role of human influence on some recent climatic changes.

Key Points

 

• New independent evidence of human contribution to recent climatic changes in the lower atmosphere
• Human influence is detected in global increases in the 500 hPa geopotential height since 1979
• A smaller natural signal is also detected in changes of the annual mean geopotential 

[40/70 Benchmark]

5 minutes ago, bluewave said:

Could also be that a warmer climate supports stronger 500 mb ridges. 
 

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2015GL066669

 

Apart from global scale surface warming, anthropogenic forcings also lead to warming and thermal expansion of the lower atmosphere. Here we investigate these effects using the geopotential height at 500 hPa, an indicator of the combined thermodynamic and dynamic climatic response to external forcings. We employ optimal fingerprinting, which uses information from reanalysis data sets and experiments with seven state-of-the-art climate models, to assess the role of anthropogenic and natural influences on changes in the geopotential height during the satellite era. A significant global increase in the annual and seasonal mean geopotential height due to human influence is detected, a result confirmed with four different reanalysis data sets. A more moderate increase in the annual mean associated with natural forcings is also detected. Our findings, consistent with previous detection and attribution studies of changes in temperature and sea level pressure, indicate the prominent role of human influence on some recent climatic changes.

Key Points

 

• New independent evidence of human contribution to recent climatic changes in the lower atmosphere
• Human influence is detected in global increases in the 500 hPa geopotential height since 1979
• A smaller natural signal is also detected in changes of the annual mean geopotential 

Yea, I'm assuming that....but it doesn't negate my point. I'm not arguing that the climate hasn't warmed or that it doesn't augment ridges...but that N Pacific pattern is more favorable in the latter composite. One had a very flat ridge with lower heights knifing through AK and one has a poleward Aleutian ridge.

[bluewave]

19 minutes ago, 40/70 Benchmark said:

Yea, I'm assuming that....but it doesn't negate my point. I'm not arguing that the climate hasn't warmed or that it doesn't augment ridges...but that N Pacific pattern is more favorable in the latter composite. One had a very flat ridge with lower heights knifing through AK and one has a poleward Aleutian ridge.

The flipside of the more poleward Aleutian ridge dropping the -EPO is also a trough tucked underneath near the West Coast. So deeper lows digging into the West also pump the Southeast Ridge. It was a much safer bet for us in a month like January 2022 when the Aleutian Ridge was able to build into the +PNA region. But most of the time since then the Aleutian Ridge axis is further west near the Dateline which allows more of a trough out West than we want. This is why I have been mentioning a mismatch pattern would be necessary to push back against this predominant winter pattern since the 15-16 super El Niño. 

[40/70 Benchmark]

17 minutes ago, bluewave said:

The flipside of the more poleward Aleutian ridge dropping the -EPO is also a trough tucked underneath near the West Coast. So deeper lows digging into the West also pump the Southeast Ridge. It was a much safer bet for us in a month like January 2022 when the Aleutian Ridge was able to build into the +PNA region. But most of the time since then the Aleutian Ridge axis is further west near the Dateline which allows more of a trough out West than we want. This is why I have been mentioning a mismatch pattern would be necessary to push back against this predominant winter pattern since the 15-16 super El Niño. 

Well, part of this is due to being at the low point of a -PDO multidecadal cycle...its a combo of that and CC.

[bluewave]

39 minutes ago, 40/70 Benchmark said:

Well, part of this is due to being at the low point of a -PDO multidecadal cycle...its a combo of that and CC.

It’s also the big changes to the -PDO making it a much warmer pattern than it was before 2014. 
 

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2022GL101078

The fundamental result of this study is that the first EOF of SST in the North Pacific has changed starting in 2014. For more than 20 years, the PDO has been used to describe the state of the North Pacific. However, since the marine heatwave of 2014, there have been remarkable changes to the dominant mode of SST in the North Pacific. The spatial pattern of the first EOF of SST from 1950 to 2021 is notably different from the PDO, suggesting that though the PDO served as a useful metric of SST variations until 2014 (Johnstone & Mantua, 2014), it may no longer be as effective a climate index for the North Pacific. From 1950 until the 2014 MHW, the first EOF remained consistent in its proportion of positive and negative regions with both taking up roughly half the area of the North Pacific (and with the positive region taken to be the eastern Pacific). When EOFs are calculated from 1950 to endpoints after 2014, the first EOF has a maximum positive region covering 77% of the North Pacific, with a PC indicating the largest anomalies on record. These changes to the first EOF/PC of North Pacific SST are nothing short of remarkable.

In concert with these changes, the second EOF/PC of SST has also undergone profound evolution since 2014. This second EOF now accounts for approximately 18% of the variability, growing from 13% during the 1950–2013 period. The spatial structure of the second EOF now is positive over almost the entire basin, with a PC that has grown strongly positive in the last several years. Thus, the second EOF/PC describes warming over much of the Pacific not in the positive lobe of the first EOF.

A relevant aspect of our analysis is that we did not remove a trend from the data before calculating the EOFs and PCs. This is consistent with the original calculations of EOFs in the North Pacific (Davis, 1976) and more recent analysis by Johnstone and Mantua (2014), but inconsistent with the definition of the PDO which did have a global mean trend removed (Mantua et al., 1997; Zhang et al., 1997). Whether or not a trend was removed had little effect on the first EOF, and thus the PDO, until 2014. Two of our results lead to this conclusion: first, our first PC calculated between 1950 and 1993 agreed with the PDO with a correlation coefficient of 0.97; and second, our first EOF calculated with successively longer time series did not change in shape until 2014. There are many approaches to removing a trend from time series (Deser & Phillips, 2021; Frankignoul et al., 2017; Solomon & Newman, 2012). We investigated two of these approaches: first we removed a least-squares fit of a line to the global average temperature as in the original definition of the PDO (Figure S2 in Supporting Information S1), and second, we removed a least-squares fit of a line from each grid point in the North Pacific (Figure S3 in Supporing Information S1). In each case the EOF analysis reproduced the PDO spatial pattern and index, suggesting that the PDO remains a good measure for the variability relative to the trend. In general, removal of a trend (as by least-squares fitting of a line, e.g.,) tends to deemphasize the ends of a record. In our analysis, the inclusion of the trend highlights the fact that the warming in the eastern Pacific has increased notably in recent years, a fact that would be obscured if a linear trend had been removed.

The PDO is recognized to be a result of many processes that may cause temperature variability (Newman et al., 2016) rather than any singular phenomenon. The many processes that affect SST have apparently combined to create both this era of frequent marine heatwaves beginning in 2014 and a fundamental change to the first mode of SST. The persistence of the marine heatwaves was studied by Di Lorenzo and Mantua (2016) who also invoked a number of interacting processes, suggesting that the variance described by the PDO would increase in a warmer climate. Di Lorenzo and Mantua (2016) explicitly removed a trend before calculating the EOFs of SST, so that their EOFs described variance relative to the trend. The PDO is based on a constant spatial pattern defined by the EOF that described the most variance of SST through the mid 1990's. However, there is no guarantee that the EOFs of SST will remain constant as climate change continues. This concern about indices based on EOFs applies also to the North Pacific Gyre Oscillation (Di Lorenzo et al., 2008), which describes variance in sea surface height.

The PDO is widely used as a measure of temperature in the eastern boundary upwelling system along the west coast of North America (e.g., Weber et al., 2021). The period of persistent marine heatwaves since 2014 has made the PDO less useful as an index of temperature in this region because it does not reflect the recent increase. In general, using PCs from a basin-wide analysis as indices of temperature for specific regions may be problematic because the influences from distant parts of the basin affect the PCs. Options moving forward may include: (a) updating the definition of the first mode of temperature variability, as we have done here, (b) explicitly accounting for the trend in addition to the PDO for a measure of temperature, or (c) defining a new temperature metric in a specified area in the region as is done for the various measures of El Niño (Trenberth, 1997) or more recently as in the NEP index (Johnstone & Mantua, 2014). Interestingly, the NEP was first published just before the recent period of MHWs, and the value of the approach championed in Johnstone and Mantua (2014) has only increased. The wide-ranging effects of the recent period of MHWs are likely to be seen in continuing studies of the eastern North Pacific.

 

 

[Stormchaserchuck1]

Highest temperature even recorded in Australia in the Winter today, 106F. This is after the great -4 to -5 AAO. I think the same pattern is present, and for some reason these negative AO and AAO events are accompanied by warmer temperatures in the mid latitudes +days. I say that to have an average to good Winter in the east, we absolutely need the Pacific in tune. 

[Stormchaserchuck1]

12 hours ago, bluewave said:

We would need a Jan 22 style mismatch pattern in order to avoid the Euro DJF La Nada strong -PDO composite. 

It's rare. These correlations aren't perfect, but what we've seen lately is the normal 0.30-0.40 correlation with the PDO, being about 0.60. 

I think we have a warm Sept-Nov coming for the CONUS, as there is a really strong correlation with the PDO in the Fall season. Going back to 1948, it has a >0.60 correlation in NW Canada (+EPO)! Having a -2 to -3 pdo should set the tone for some above normal ridging going forward. 

[snowman19]

12 minutes ago, Stormchaserchuck1 said:

It's rare. These correlations aren't perfect, but what we've seen lately is the normal 0.30-0.40 correlation with the PDO, being about 0.60. 

I think we have a warm Sept-Nov coming for the CONUS, as there is a really strong correlation with the PDO in the Fall season. Going back to 1948, it has a >0.60 correlation in NW Canada (+EPO)! Having a -2 to -3 pdo should set the tone for some above normal ridging going forward. 

Completely agree. Everything I’m seeing globally supports a warmer and drier than normal fall (SON)

[40/70 Benchmark]

3 hours ago, bluewave said:

It’s also the big changes to the -PDO making it a much warmer pattern than it was before 2014. 
 

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2022GL101078

The fundamental result of this study is that the first EOF of SST in the North Pacific has changed starting in 2014. For more than 20 years, the PDO has been used to describe the state of the North Pacific. However, since the marine heatwave of 2014, there have been remarkable changes to the dominant mode of SST in the North Pacific. The spatial pattern of the first EOF of SST from 1950 to 2021 is notably different from the PDO, suggesting that though the PDO served as a useful metric of SST variations until 2014 (Johnstone & Mantua, 2014), it may no longer be as effective a climate index for the North Pacific. From 1950 until the 2014 MHW, the first EOF remained consistent in its proportion of positive and negative regions with both taking up roughly half the area of the North Pacific (and with the positive region taken to be the eastern Pacific). When EOFs are calculated from 1950 to endpoints after 2014, the first EOF has a maximum positive region covering 77% of the North Pacific, with a PC indicating the largest anomalies on record. These changes to the first EOF/PC of North Pacific SST are nothing short of remarkable.

In concert with these changes, the second EOF/PC of SST has also undergone profound evolution since 2014. This second EOF now accounts for approximately 18% of the variability, growing from 13% during the 1950–2013 period. The spatial structure of the second EOF now is positive over almost the entire basin, with a PC that has grown strongly positive in the last several years. Thus, the second EOF/PC describes warming over much of the Pacific not in the positive lobe of the first EOF.

A relevant aspect of our analysis is that we did not remove a trend from the data before calculating the EOFs and PCs. This is consistent with the original calculations of EOFs in the North Pacific (Davis, 1976) and more recent analysis by Johnstone and Mantua (2014), but inconsistent with the definition of the PDO which did have a global mean trend removed (Mantua et al., 1997; Zhang et al., 1997). Whether or not a trend was removed had little effect on the first EOF, and thus the PDO, until 2014. Two of our results lead to this conclusion: first, our first PC calculated between 1950 and 1993 agreed with the PDO with a correlation coefficient of 0.97; and second, our first EOF calculated with successively longer time series did not change in shape until 2014. There are many approaches to removing a trend from time series (Deser & Phillips, 2021; Frankignoul et al., 2017; Solomon & Newman, 2012). We investigated two of these approaches: first we removed a least-squares fit of a line to the global average temperature as in the original definition of the PDO (Figure S2 in Supporting Information S1), and second, we removed a least-squares fit of a line from each grid point in the North Pacific (Figure S3 in Supporing Information S1). In each case the EOF analysis reproduced the PDO spatial pattern and index, suggesting that the PDO remains a good measure for the variability relative to the trend. In general, removal of a trend (as by least-squares fitting of a line, e.g.,) tends to deemphasize the ends of a record. In our analysis, the inclusion of the trend highlights the fact that the warming in the eastern Pacific has increased notably in recent years, a fact that would be obscured if a linear trend had been removed.

The PDO is recognized to be a result of many processes that may cause temperature variability (Newman et al., 2016) rather than any singular phenomenon. The many processes that affect SST have apparently combined to create both this era of frequent marine heatwaves beginning in 2014 and a fundamental change to the first mode of SST. The persistence of the marine heatwaves was studied by Di Lorenzo and Mantua (2016) who also invoked a number of interacting processes, suggesting that the variance described by the PDO would increase in a warmer climate. Di Lorenzo and Mantua (2016) explicitly removed a trend before calculating the EOFs of SST, so that their EOFs described variance relative to the trend. The PDO is based on a constant spatial pattern defined by the EOF that described the most variance of SST through the mid 1990's. However, there is no guarantee that the EOFs of SST will remain constant as climate change continues. This concern about indices based on EOFs applies also to the North Pacific Gyre Oscillation (Di Lorenzo et al., 2008), which describes variance in sea surface height.

The PDO is widely used as a measure of temperature in the eastern boundary upwelling system along the west coast of North America (e.g., Weber et al., 2021). The period of persistent marine heatwaves since 2014 has made the PDO less useful as an index of temperature in this region because it does not reflect the recent increase. In general, using PCs from a basin-wide analysis as indices of temperature for specific regions may be problematic because the influences from distant parts of the basin affect the PCs. Options moving forward may include: (a) updating the definition of the first mode of temperature variability, as we have done here, (b) explicitly accounting for the trend in addition to the PDO for a measure of temperature, or (c) defining a new temperature metric in a specified area in the region as is done for the various measures of El Niño (Trenberth, 1997) or more recently as in the NEP index (Johnstone & Mantua, 2014). Interestingly, the NEP was first published just before the recent period of MHWs, and the value of the approach championed in Johnstone and Mantua (2014) has only increased. The wide-ranging effects of the recent period of MHWs are likely to be seen in continuing studies of the eastern North Pacific.

 

 

 

23 minutes ago, Stormchaserchuck1 said:

Highest temperature even recorded in Australia in the Winter today, 106F. This is after the great -4 to -5 AAO. I think the same pattern is present, and for some reason these negative AO and AAO events are accompanied by warmer temperatures in the mid latitudes +days. I say that to have an average to good Winter in the east, we absolutely need the Pacific in tune. 

I agree with this. We don't have the margin for error that we used to, but I also think that some of this in the northern hemisphere is due to the +AMO as well.

[bluewave]

21 minutes ago, 40/70 Benchmark said:

 

I agree with this. We don't have the margin for error that we used to, but I also think that some of this in the northern hemisphere is due to the +AMO as well.

Yeah, I also believe the record warmth in the Atlantic is enhancing the Southeast Ridge. 

[Terpeast]

While the upcoming winter looks ugly on a seasonal time scale, I think it's interesting that we have had one significant BN period in the east this month and another one coming in early September. If this is a sign of things to come, 2 maybe 3 periods of significant cold should be in play in an otherwise warm winter. Kind of like last year.

[GaWx]

 

[GaWx]

 Nino 3.4 appears to be steadily cooling now:

OISST:

CDAS:

 

Buoys: E 3.4 is the coolest I’ve seen it and has been cooling rather rapidly the last few days even though it’s still warm in Nino 4:

 

SOIs have gone solidly positive 11 days and look to continue.

[40/70 Benchmark]

1 hour ago, bluewave said:

Yeah, I also believe the record warmth in the Atlantic is enhancing the Southeast Ridge. 

Its several different factors, which definitely includes CC.

[40/70 Benchmark]

29 minutes ago, GaWx said:

 

Would love that to persist into the cold season. 

[GaWx]

12 minutes ago, 40/70 Benchmark said:

Would love that to persist into the cold season. 

It’s strange. Out of the 10 listed day 8 analogs, 8 of the 10 are from El Niño late August or Septembers: 3 from 2009, 2 from 2006, 1 from 1987, 1 from 1972, and 1 from 1953. The only 2 not Nino are from 2003 and 1981, both neutral. So, no dates from La Nina are listed!

 Is this significant or is it just a not unusual short period that goes against the grain and will go back to La Niña soon?

[Terpeast]

38 minutes ago, GaWx said:

It’s strange. Out of the 10 listed day 8 analogs, 8 of the 10 are from El Niño late August or Septembers: 3 from 2009, 2 from 2006, 1 from 1987, 1 from 1972, and 1 from 1953. The only 2 not Nino are from 2003 and 1981, both neutral. So, no dates from La Nina are listed!

 Is this significant or is it just a not unusual short period that goes against the grain and will go back to La Niña soon?

Most likely short term, but I think we will see a few deviations away from the nina base state going forward. Those cannot be predicted on a seasonal time scale, though

[bluewave]

11 hours ago, GaWx said:

It’s strange. Out of the 10 listed day 8 analogs, 8 of the 10 are from El Niño late August or Septembers: 3 from 2009, 2 from 2006, 1 from 1987, 1 from 1972, and 1 from 1953. The only 2 not Nino are from 2003 and 1981, both neutral. So, no dates from La Nina are listed!

 Is this significant or is it just a not unusual short period that goes against the grain and will go back to La Niña soon?

Yeah, the quieter Atlantic in late August and that big ridge forecast over Canada to start September matches the MJO 5 composite for this time of year.

 

 

[snowman19]

11 hours ago, GaWx said:

 

It’s him finding a way out of his forecast. Just an excuse. He’s been hyping a huge Atlantic hurricane season since the spring. You see this tactic with winter forecasts, they will find anything to say “my forecast would have been right if it wasn’t for the completely unexpected, unseen X that happened, no one could have possibly seen this coming!” @bluewave has shown how strong the large scale Niña like forcing has been for months now. It will not be 100% of the time and that applies to any type of forcing, there will be small scale temporary/transient anomalies and deviations from time to time