2021 Indicators: SST's / SAL / MSLP / Shear / Steering / Instability / Sat Images

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Re: 2021 Indicators: SST's / SAL / MSLP / Shear / Steering / Instability / Sat Images

#4081 Postby Category5Kaiju » Mon Oct 18, 2021 6:16 pm

Hammy wrote:
Category5Kaiju wrote:
aspen wrote:Perhaps something is changing with the global base state that’ll continue into 2022. Does anyone know how the THC is doing? I know THC collapse gets tossed around all the time and never happens, but with such an abnormal lull in activity that defies climo, it’s for once not totally out of the question.


From my understanding, one could not have predicted a 2013 given how 2012 finished off, with major strength cyclones and fair amounts of activity seen in all 3 NH basins in October (in other words, 2012 ended and behaved like a typical year would have). The best analog I can think of for what we are seeing now is 2007, and even then activity was fairly decent in the WPAC while the EPAC and Atlantic were quiet. 2008 of course turned out to be a very active Atlantic year, with the WPAC and EPAC being below average but featuring their fair share of powerful storms. I think it's too early to say that what we are seeing now is going to lead to a 2013 repeat next year, and especially with individual hurricane/typhoon season behavior, because each year is so unique in the sequence of storms, their strengths, where they hit, etc., historical seasons can only go so far in serving as useful predictions for what to expect exactly in future seasons.

I think it is also important to understand that a THC collapse as severe and unexpected as 2013 should not be expected to occur during any given year. The way I see it is that the conditions that caused 2013 to occur were highly unique and fortuitious, and imho saying in a given year that another 2005 will happen or that another 2013 will happen are just things one should never say given how unlikely such extreme events are to occur in the first place in any year.


Regarding the THC collapse, it's best not to use it as a prediction tool, and really impossible to determine 8-10 months out if it'll be a factor in next hurricane season. However it's a good question to ask as far as present conditions go--in 2013 it occurred during springtime, and had continuing effects into summer. I don't know what the SST pattern was that related to that, rather than other cycles, nor do I know where to find archival SST maps for this year, but it's certainly something that should would warrant after the fact investigating, especially given one of the more noticeable things outside of hurricane activity was the upper air pattern and fronts not matching with the seasons.


From what I can remember, one glaring, unusual sst profile of the Atlantic in 2013 was how warm the subtropics were compared to the deep tropics; in fact, weren't you active on Storm2k when 2013 occurred? I myself joined in 2020 so I wonder what it must have been like to be on this forum tracking one of the worst and most unexpectedly underperforming seasons of all time
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Re: 2021 Indicators: SST's / SAL / MSLP / Shear / Steering / Instability / Sat Images

#4082 Postby tolakram » Mon Oct 18, 2021 6:32 pm

AlphaToOmega wrote:At this point, I feel like we forgot that the MJO exists. :lol: :lol: :lol:


The MJO is not everything, it's just another indicator. Not every year needs all the favorable indicators to line up in order to get a storm. Not recognizing something else is creating this unusual pause in activity is a mistake, IMO. Is it simply bad MJO timing, is it the length of the cycle + bad timing, etc.
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Re: 2021 Indicators: SST's / SAL / MSLP / Shear / Steering / Instability / Sat Images

#4083 Postby Yellow Evan » Mon Oct 18, 2021 7:07 pm

Category5Kaiju wrote:
Hammy wrote:
Category5Kaiju wrote:
From my understanding, one could not have predicted a 2013 given how 2012 finished off, with major strength cyclones and fair amounts of activity seen in all 3 NH basins in October (in other words, 2012 ended and behaved like a typical year would have). The best analog I can think of for what we are seeing now is 2007, and even then activity was fairly decent in the WPAC while the EPAC and Atlantic were quiet. 2008 of course turned out to be a very active Atlantic year, with the WPAC and EPAC being below average but featuring their fair share of powerful storms. I think it's too early to say that what we are seeing now is going to lead to a 2013 repeat next year, and especially with individual hurricane/typhoon season behavior, because each year is so unique in the sequence of storms, their strengths, where they hit, etc., historical seasons can only go so far in serving as useful predictions for what to expect exactly in future seasons.

I think it is also important to understand that a THC collapse as severe and unexpected as 2013 should not be expected to occur during any given year. The way I see it is that the conditions that caused 2013 to occur were highly unique and fortuitious, and imho saying in a given year that another 2005 will happen or that another 2013 will happen are just things one should never say given how unlikely such extreme events are to occur in the first place in any year.


Regarding the THC collapse, it's best not to use it as a prediction tool, and really impossible to determine 8-10 months out if it'll be a factor in next hurricane season. However it's a good question to ask as far as present conditions go--in 2013 it occurred during springtime, and had continuing effects into summer. I don't know what the SST pattern was that related to that, rather than other cycles, nor do I know where to find archival SST maps for this year, but it's certainly something that should would warrant after the fact investigating, especially given one of the more noticeable things outside of hurricane activity was the upper air pattern and fronts not matching with the seasons.


From what I can remember, one glaring, unusual sst profile of the Atlantic in 2013 was how warm the subtropics were compared to the deep tropics; in fact, weren't you active on Storm2k when 2013 occurred? I myself joined in 2020 so I wonder what it must have been like to be on this forum tracking one of the worst and most unexpectedly underperforming seasons of all time


2013 had a sudden weakening of the THC that resulted in a reversal of the +AMO configuration (I can post images if you like but it happened in the late spring). We weren’t really aware of it at the time but it’s something we should be able to detect if it were to happen again given how often we scrutinize SST configurations on this forum. I’m not seeing any signs of a flip right now.

The Atlantic is doing poorly this month due to MJO in the Pacific and the 500 mbar pattern over North America being basically the opposite of last year, which is shearing the Caribbean.
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Re: 2021 Indicators: SST's / SAL / MSLP / Shear / Steering / Instability / Sat Images

#4084 Postby aspen » Tue Oct 19, 2021 7:12 am

If 2021 has zero named storms form in October, it’ll be the first occurrence since 2015, which was a Super El Niño. Having a dead October in the Atlantic during a La Niña year is almost unheard of. The only other instances of no TS or stronger systems forming in October since 1980 (2015, 2006, 2002, 1994, 1993, 1986, 1983, and 1982) were all El Niño and/or -AMO years.
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Re: 2021 Indicators: SST's / SAL / MSLP / Shear / Steering / Instability / Sat Images

#4085 Postby Category5Kaiju » Tue Oct 19, 2021 7:38 am

While I understand how many of us like to focus on the Atlantic basin and not the other Pacific basins, what's even more shocking imho is how there has not been an active major strength cyclone ANYWHERE in the WPAC, EPAC, or the Atlantic since Sam very early this month. 2007 is getting thrown around quite a bit, but whatever happened in 2007 that caused a dead Atlantic in October cannot explain why so far there has not been a SINGLE NS in sight (and with this expected for the next weeks or so) and why there has not been a single WPAC typhoon that reached Cat 3 or higher yet. 1978 was the last year to feature this sort of global inactivity, but even then by now the WPAC was about to see Typhoon Rita, which would go on to become a monster 878 mbar typhoon. Something like that is not happening anytime soon from what I understand as of currently.
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Re: 2021 Indicators: SST's / SAL / MSLP / Shear / Steering / Instability / Sat Images

#4086 Postby kevin » Tue Oct 19, 2021 8:20 am

Category5Kaiju wrote:While I understand how many of us like to focus on the Atlantic basin and not the other Pacific basins, what's even more shocking imho is how there has not been an active major strength cyclone ANYWHERE in the WPAC, EPAC, or the Atlantic since Sam very early this month. 2007 is getting thrown around quite a bit, but whatever happened in 2007 that caused a dead Atlantic in October cannot explain why so far there has not been a SINGLE NS in sight (and with this expected for the next weeks or so) and why there has not been a single WPAC typhoon that reached Cat 3 or higher yet. 1978 was the last year to feature this sort of global inactivity, but even then by now the WPAC was about to see Typhoon Rita, which would go on to become a monster 878 mbar typhoon. Something like that is not happening anytime soon from what I understand as of currently.


Yes it's incredible how quiet the TC season has been in October worldwide so far, not just in the Atlantic. Here's the most intense (= lowest pressure) TC in October (globally) for each year since 2000. 2021's October isn't done yet, but right now its 975 mb value is the least intense one in the 21st century. Based on a normal distribution of the last 20 years we get an average of 915.1 mb with a standard deviation of 22.8 mb. That means that the statistical chance of 975 mb being the most intense month in a random October month would be ~0.4% or roughly 1 in 250. 2000 was already remarkable with Xangsane, a 960mb cat 2, being the most intense storm of the month but a 975 mb storm would really be a major statistical anomaly.

Year / Name / Basin / Pressure (mb) / Wind (mph) / Cat

2021 / Kompasu / WPAC / 975 / 65 / TS
2020 / Goni / WPAC / 905 / 195 / 5

2019 / Hagibis / WPAC / 915 / 185 / 5
2018 / Yutu / WPAC / 900 / 175 / 5
2017 / Lan / WPAC / 915 / 155 / 4
2016 / Haima / WPAC / 900 / 165 / 5
2015 / Patricia / EPAC / 872 / 215 / 5
2014 / Vongfong / WPAC / 900 / 180 / 5
2013 / Lekima / WPAC / 905 / 160 / 5
2012 / Sandy / NATL / 940 / 115 / 3
2011 / Jova / EPAC / 955 / 125 / 3
2010 / Megi / WPAC / 885 / 185 / 5

2009 / Rick / EPAC / 906 / 180 / 5
2008 / Norbert / EPAC / 945 / 130 / 4
2007 / Krosa / WPAC / 925 / 155 / 4
2006 / Cimaron / WPAC / 920 / 160 / 5
2005 / Wilma / NATL / 882 / 185 / 5
2004 / Ma-on / WPAC / 920 / 160 / 5
2003 / Parma/ WPAC / 930 / 135 / 4
2002 / Kenna / EPAC / 913 / 165 / 5
2001 / Podul / WPAC / 925 / 185 / 5
2000 / Xangsane / WPAC / 960 / 105 / 2
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Re: 2021 Indicators: SST's / SAL / MSLP / Shear / Steering / Instability / Sat Images

#4087 Postby SFLcane » Tue Oct 19, 2021 11:11 am

It was a wild start to the season no doubt but for me personally I was not expecting the season to just come to a screeching halt. If your were hit it the season was bad if not as in the case for Florida the luck continues. Wishing everyone happy holidays and enjoy the off season.

I sure will.

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 https://twitter.com/derekortt/status/1450491118836142080


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Re: 2021 Indicators: SST's / SAL / MSLP / Shear / Steering / Instability / Sat Images

#4088 Postby aspen » Tue Oct 19, 2021 11:19 am

Nobody is gonna be saying 2004 and 2017 came to a screeching halt anymore lol.

I remember talks during September 2020 about it not behaving like a -ENSO year. Well, for all those who said that…here’s your Atlantic not behaving like a -ENSO year. If this is a sign that the 2021-22 La Niña event is not going to be like a normal Nina, could this have more impacts down the line for CONUS wind patterns and perhaps next year’s ENSO state? Could an atmosphere that lacks normal Nina patterns be more susceptible to transitioning into a +ENSO?

2021 has simultaneously been one of the most impressive and most pathetic seasons I’ve ever seen — a mix of record breaking bursts of activity and extremely abnormal droughts, very intense and high-ACE majors mixed with a ton of shorties and struggle-storms. While many seasons have lows and highs in activity, 2021’s were so pronounced and so at odds with each other. Hopefully 2022 will be less of a headache.
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Re: 2021 Indicators: SST's / SAL / MSLP / Shear / Steering / Instability / Sat Images

#4089 Postby cycloneye » Tue Oct 19, 2021 11:30 am

Oh my. Looks like a funeral in here but for a reason the season ends officially on November 30th.
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Re: 2021 Indicators: SST's / SAL / MSLP / Shear / Steering / Instability / Sat Images

#4090 Postby Category5Kaiju » Tue Oct 19, 2021 11:36 am

Whatever happens in the next month and a half before the season officially ends, I think in the future we are going to have to do some very heavy and extensive studies on why this year's October behaved like it did. Clearly all of the previously known factors that could kill a season unexpectedly, like what we saw with 2013, do not seem to be at play here. This seems to be a totally different beast.
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Re: 2021 Indicators: SST's / SAL / MSLP / Shear / Steering / Instability / Sat Images

#4091 Postby Ubuntwo » Tue Oct 19, 2021 1:22 pm

Category5Kaiju wrote:Whatever happens in the next month and a half before the season officially ends, I think in the future we are going to have to do some very heavy and extensive studies on why this year's October behaved like it did. Clearly all of the previously known factors that could kill a season unexpectedly, like what we saw with 2013, do not seem to be at play here. This seems to be a totally different beast.

A suppressive kelvin wave is destructively interfering with the MJO (per the CPC) which explains the current lull and an out of phase MJO explains Atlantic inactivity in early October. The persistent TUTT feature has also been shearing out waves in the Caribbean. Doesn’t seem like a huge mystery.

In the WPAC, Kompasu had potential but was just too broad and expansive as a monsoon gyre with interacting areas of vorticity.
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Re: 2021 Indicators: SST's / SAL / MSLP / Shear / Steering / Instability / Sat Images

#4092 Postby tolakram » Tue Oct 19, 2021 1:33 pm

Ubuntwo wrote:
Category5Kaiju wrote:Whatever happens in the next month and a half before the season officially ends, I think in the future we are going to have to do some very heavy and extensive studies on why this year's October behaved like it did. Clearly all of the previously known factors that could kill a season unexpectedly, like what we saw with 2013, do not seem to be at play here. This seems to be a totally different beast.

A suppressive kelvin wave is destructively interfering with the MJO (per the CPC) which explains the current lull and an out of phase MJO explains Atlantic inactivity in early October. The persistent TUTT feature has also been shearing out waves in the Caribbean. Doesn’t seem like a huge mystery.

-snip-


Why hasn't this happened before? The mystery is why this is happening and how it can be predicted to improve seasonal forecasting. This is more than just the Atlantic though, the global slowdown is undeniable. If we end up with an active November, and at this point who really knows, this will get even more interesting.
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Re: 2021 Indicators: SST's / SAL / MSLP / Shear / Steering / Instability / Sat Images

#4093 Postby AlphaToOmega » Tue Oct 19, 2021 1:38 pm

The CFSv2 still shows favorable conditions for late October and early November, and this coincides with the GEFS detecting favorable conditions.

Image
Image
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Re: 2021 Indicators: SST's / SAL / MSLP / Shear / Steering / Instability / Sat Images

#4094 Postby Spacecoast » Tue Oct 19, 2021 2:36 pm

Hurricane landfalls in November are relatively rare...
Since 1850,(last 171 years), 21 Atlantic Hurricanes made landfall after November 1st.

November Hurricane Landfalls:
Image
*Texas, Louisiana,Alabama, Mississippi, Georgia, South Carolina, Puerto Rico, and Dominican Republic have never had November landfall.
I believe this list is complete, but I may have missed some small islands...

Only 3 Hurricanes have ever made Nov CONUS landfall, two in Florida, one OBX, NC:
Nov 21, 1985 KATE 1985 CAT2 MEXICO BEACH, FL
Nov 4 1935 UNNAMED 1935 CAT2 MIAMI, FL
Nov 2, 1861 UNNAMED 1861 CAT1 OBX, NC

6 Hurricanes made Nov Cuba landfall:
Nov 9, 2008 PALOMA 2008 CAT2
Nov 4, 2001 MICHELLE 2001 CAT4
Nov 6, 1981 KATRINA 1981 CAT1
Nov 6, 1942 UNNAMED 1942 CAT1 (CUBA,BELIZE)
Nov 9, 1932 UNNAMED 1932 CAT4
Nov 7, 1906 UNNAMED 1906 CAT1

5 Hurricanes made Nov Nicaragua landfall:
Nov 17, 2020 IOTA 2020 CAT4
Nov 3, 2020 ETA 2020 CAT4
Nov 24, 2016 OTTO 2016 CAT3
Nov 5, 2009 IDA 2009 CAT1
Nov 4, 1887 UNNAMED 1887 CAT1

2 Hurricanes made Nov Jamaica landfall:
Nov 18, 1912 UNNAMED 1912 CAT3
Nov 2, 1872 UNNAMED 1874 CAT2

2 Hurricanes made Nov Haiti landfall:
Nov 12, 1909 UNNAMED 1909 CAT1
Nov 27, 1887 UNNAMED 1887 CAT1


1 Hurricane made Nov Honduras landfall:
Nov 3, 1898 UNNAMED 1898 CAT1

1 Hurricane made Nov Mexico landfall:
Nov 1, 1870 UNNAMED 1870 CAT1

1 Hurricane made Nov St. Martin / St. Bart landfall:
Nov 19,1999 Lenny 1999 CAT2
Last edited by Spacecoast on Tue Oct 19, 2021 3:17 pm, edited 4 times in total.
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Re: 2021 Indicators: SST's / SAL / MSLP / Shear / Steering / Instability / Sat Images

#4095 Postby Category5Kaiju » Tue Oct 19, 2021 2:48 pm

Spacecoast wrote:Hurricane landfalls in November are relatively rare...
Since 1850,(last 171 years), 20 Atlantic Hurricanes made landfall after November 1st.

November Hurricane Landfalls:
[url]https://i.ibb.co/j4nGwL0/frcstK.jpg [/url]
*Texas, Louisiana, Mississippi, Georgia, South Carolina, Puerto Rico, and Dominican Republic have never had November landfall.
I believe this list is complete, but I may have missed some small islands...

Only 3 Hurricanes have ever made Nov CONUS landfall, two in Florida, one OBX, NC:
Nov 21, 1985 KATE 1985 CAT2 MEXICO BEACH, FL
Nov 4 1935 UNNAMED 1935 CAT2 MIAMI, FL
Nov 2, 1861 UNNAMED 1861 CAT1 OBX, NC

6 Hurricanes made Nov Cuba landfall:
Nov 9, 2008 PALOMA 2008 CAT2 CUBA
Nov 4, 2001 MICHELLE 2001 CAT4 CUBA
Nov 6, 1981 KATRINA 1981 CAT1 CUBA
Nov 6, 1942 UNNAMED 1942 CAT1 CUBA,BELIZE
Nov 9, 1932 UNNAMED 1932 CAT4 CUBA
Nov 7, 1906 UNNAMED 1906 CAT1 CUBA

5 Hurricanes made Nov Nicaragua landfall:
Nov 17, 2020 IOTA 2020 CAT4 NICARAGUA
Nov 3, 2020 ETA 2020 CAT4 NICARAGUA
Nov 24, 2016 OTTO 2016 CAT3 NICARAGUA
Nov 5, 2009 IDA 2009 CAT1 NICARAGUA
Nov 4, 1887 UNNAMED 1887 CAT1 NICARAGUA

2 Hurricanes made Nov Jamaica landfall:
Nov 18, 1912 UNNAMED 1912 CAT3 JAMAICA
Nov 2, 1872 UNNAMED 1874 CAT2 JAMAICA

2 Hurricanes made Nov Haiti landfall:
Nov 12, 1909 UNNAMED 1909 CAT1 HAITI
Nov 27, 1887 UNNAMED 1887 CAT1 HAITI

1 Hurricane made Nov Honduras landfall:
Nov 3, 1898 UNNAMED 1898 CAT1 HONDURAS

1 Hurricane made Nov Mexico landfall:
Nov 1, 1870 UNNAMED 1870 CAT1 Mexico


Where’s Lenny?
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Re: 2021 Indicators: SST's / SAL / MSLP / Shear / Steering / Instability / Sat Images

#4096 Postby Ubuntwo » Tue Oct 19, 2021 3:21 pm

2-wk moderate confidence area in the Caribbean. Three AOIs across the Pacific.
Image

RMM observations show the Madden-Julian Oscillation (MJO) has weakened substantially, falling within the unit circle over the West Pacific during the last week. This weakening in RMM space is likely tied to destructive interference with the emerging low frequency base state, where a La Nina advisory has been recently issued, with an 87% chance of La Nina conditions favored during boreal winter. However, the velocity potential based MJO index, and objective wavenumber-frequency filtering of upper-level velocity potential anomalies continue to reflect eastward propagation of the intraseasonal signal east of the Date Line, which is also supported by the recent relaxation of anomalous westerlies aloft and enhanced trades observed over the equatorial Pacific.


Although most model ensemble means remain confined within the RMM unit circle indicative of a weak MJO through early November, there are several ensemble members depicting a higher amplitude intraseasonal event over phases 8 and 1, which is noteworthy when considering RMM values have been skewed towards phases 4 and 5 due to the persistence of enhanced convection favored over the Maritime Continent tied to the building La Nina. In light of all this, tropical cyclone (TC) activity is favored over the East Pacific in the near-term, with increasingly favorable conditions for development over the Atlantic basin during late October and into early November.
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Re: 2021 Indicators: SST's / SAL / MSLP / Shear / Steering / Instability / Sat Images

#4097 Postby Hammy » Tue Oct 19, 2021 3:36 pm

Yellow Evan wrote:2013 had a sudden weakening of the THC that resulted in a reversal of the +AMO configuration (I can post images if you like but it happened in the late spring). We weren’t really aware of it at the time but it’s something we should be able to detect if it were to happen again given how often we scrutinize SST configurations on this forum. I’m not seeing any signs of a flip right now.



That would be interesting, I'm not familiar enough with how the various SST signals look beyond El NIno/La Nina to readily pick it out on my own.

What was the global setup during October in 1975, 81, and 2011? If the THC is not a factor this year these are possible analogs, at least based on the Atlantic side. This year, from mid-August through the end of September, we had six hurricanes, four of which were majors, and one of those (Sam) carried over into October as a major hurricane.

1975 was reasonably active (for the period at least), with five hurricanes (three were majors) from during that period, with Gladys carrying over similarly to Sam, and then there was nothing at all until Hallie on October 24.
1981 saw the same--five hurricanes with three being majors, several recurves, and then nothing until Jose on October 29. Like Hallie, this was of non-tropical origin and short-lived.
2011 had five hurricanes again, two of which were majors, but Ophelia became a major hurricane in early October, giving us a carryover similar to 2021 and 1975. There was nothing until October 23, which was Rina, though it's unlikely we'll get a NW Caribbean major this year.

All three years saw recurves, and 1975's tracks are moderately similar to this year, 2011 had a lengthy gap of inactivity during mid-September, 1975/2021 both saw major hurricane landfalls in the US and Mexican Gulf Coasts, and all four years saw little to no activity the first half of August.
Last edited by Hammy on Tue Oct 19, 2021 4:02 pm, edited 1 time in total.
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Re: 2021 Indicators: SST's / SAL / MSLP / Shear / Steering / Instability / Sat Images

#4098 Postby Category5Kaiju » Tue Oct 19, 2021 3:42 pm

Ubuntwo wrote:2-wk moderate confidence area in the Caribbean. Three AOIs across the Pacific.
https://cdn.discordapp.com/attachments/494079865050497041/900115473570603018/image0.jpg

RMM observations show the Madden-Julian Oscillation (MJO) has weakened substantially, falling within the unit circle over the West Pacific during the last week. This weakening in RMM space is likely tied to destructive interference with the emerging low frequency base state, where a La Nina advisory has been recently issued, with an 87% chance of La Nina conditions favored during boreal winter. However, the velocity potential based MJO index, and objective wavenumber-frequency filtering of upper-level velocity potential anomalies continue to reflect eastward propagation of the intraseasonal signal east of the Date Line, which is also supported by the recent relaxation of anomalous westerlies aloft and enhanced trades observed over the equatorial Pacific.


Although most model ensemble means remain confined within the RMM unit circle indicative of a weak MJO through early November, there are several ensemble members depicting a higher amplitude intraseasonal event over phases 8 and 1, which is noteworthy when considering RMM values have been skewed towards phases 4 and 5 due to the persistence of enhanced convection favored over the Maritime Continent tied to the building La Nina. In light of all this, tropical cyclone (TC) activity is favored over the East Pacific in the near-term, with increasingly favorable conditions for development over the Atlantic basin during late October and into early November.


Oh ok, so now the global tropics seem ready to go back to typical activity instead of this deathly quiet, unusual silence
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storminabox
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Re: 2021 Indicators: SST's / SAL / MSLP / Shear / Steering / Instability / Sat Images

#4099 Postby storminabox » Tue Oct 19, 2021 6:59 pm

tolakram wrote:
AlphaToOmega wrote:At this point, I feel like we forgot that the MJO exists. :lol: :lol: :lol:


The MJO is not everything, it's just another indicator. Not every year needs all the favorable indicators to line up in order to get a storm. Not recognizing something else is creating this unusual pause in activity is a mistake, IMO. Is it simply bad MJO timing, is it the length of the cycle + bad timing, etc.



Something seems to be off worldwide. Definitely not the October many were expecting. Maybe Sam was the final act of this season. If so, it was a great one.
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abajan
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Re: 2021 Indicators: SST's / SAL / MSLP / Shear / Steering / Instability / Sat Images

#4100 Postby abajan » Tue Oct 19, 2021 7:13 pm

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