2023 Indicators (SST, SAL, MSLP, Wind shear, Steering, Instability) and Day 16+ Models

[zzzh]

East Atlantic ssta is near 2005, 2010 , 2020 level , MDR is also warming up.


Long range GEFS/EPS both showed relaxed trades in tropical Atlantic.
I think this level of warmth in the Atlantic will somewhat inhibit the development of El Nino.

[DorkyMcDorkface]

In terms of a Niño/warm tropical Atlantic combo '97 comes to mind, which was of course dead during ASO despite an active start. There was a decent +AMO signatire, but imo what really stands out is the +AMM, which also would've been favorable had there been no Niño.



That being said however I don't think we will get to Super Niño status like that event, 1997-98 was very much towards the upper echelon of +ENSO events. Still though, even though a warm Atlantic can serve to counter Niño effects to an extent, there is a good chance it may not matter too much in the end, but we'll see I guess. A lot of it will likely depend on the strength of this event. If the Niño will be anything like what much of the seasonal guidance is suggesting then it probably won't make much of a difference. From what I've seen it's seems like it's really only during the warm-neutral or weaker/ CP-based Niño years (2018-2019 and 2019-2020 come to mind) where it can be effective in enhancing favorability in the Atlantic in the face of hostile ENSO.

That's just my two cents tho. Anyway back to hibernation

[Category5Kaiju]

In terms of a Niño/warm tropical Atlantic combo '97 comes to mind, which was of course dead during ASO despite an active start. There was a decent +AMO signatire, but imo what really stands out is the +AMM, which also would've been favorable had there been no Niño.

https://i.ibb.co/CM7s2rc/anomnight-6-2-1997.gif

That being said however I don't think we will get to Super Niño status like that event, 1997-98 was very much towards the upper echelon of +ENSO events. Still though, even though a warm Atlantic can serve to counter Niño effects to an extent, there is a good chance it may not matter too much in the end, but we'll see I guess. A lot of it will likely depend on the strength of this event. If the Niño will be anything like what much of the seasonal guidance is suggesting then it probably won't make much of a difference. From what I've seen it's seems like it's really only during the warm-neutral or weaker/ CP-based Niño years (2018-2019 and 2019-2020 come to mind) where it can be effective in enhancing favorability in the Atlantic in the face of hostile ENSO.

That's just my two cents tho. Anyway back to hibernation

I’m very curious to see what the mid-April sst anomalies looked like in 1951 and 1963. Those were moderate Nino years that ended up with more than 115 ACE in the Atlantic (3 major hurricanes in each season, with 1963’s strongest storm being the deadly and destructive Category 4 Hurricane Flora)

[DorkyMcDorkface]

Something I forgot to allude to is how the African Standing Wave could factor into the equation. We already know a prominent -VP cell over Africa has the potential to compete with -VP over the Pacific as exhibited by our last two +ENSO events (2018-19 and 2019-20) but once again, how much of a difference will it make if this developing Niño event ends up developing faster and takes on more canonical characteristics? In those two aforementioned cases it helped keep any significant progress towards El Niño at bay during the summer and throughout ASO (they remained warm-neutral until the winter) but if our upcoming episode gets going sooner how much influence will Africa have?

(guess I'm not in hibernation mode after all )

[DorkyMcDorkface]

Here's some food for thought:
 https://twitter.com/AndyHazelton/status/1646200505666879569



 https://twitter.com/AndyHazelton/status/1646200507478818840



 https://twitter.com/AndyHazelton/status/1646200509093625859

[cycloneye]

Dang.

 https://twitter.com/BenNollWeather/status/1646251938831532032

[Category5Kaiju]

Dang.

https://twitter.com/BenNollWeather/status/1646251938831532032

You can also vaguely see the subtropics being not as impressive as the deep tropics and Far Eastern Atlantic corridor sst-anomaly-wise. It's interesting to see how models sort of like the idea of that kind of pattern (cool subtropics, warm tropics) in the season, which isn't exactly something that many recent hurricane seasons have seen. Would be funny if this season ends up El Nino but features more tropical Atlantic instability than some of our recent past La Nina seasons

[cycloneye]

Let the spring barrier pass and then we watch in real time what transpires.

 https://twitter.com/AndyHazelton/status/1646913465028853760

[DorkyMcDorkface]

Let the spring barrier pass and then we watch in real time what transpires.

https://twitter.com/AndyHazelton/status/1646913465028853760

You can sometimes get sporadic activity in the eastern/central MDR if a well timed MJO or CCKW passage interacts with a well-defined TW, which can provide a small pocket of less hostile conditions inside the overall unfavorable background state, even during stronger Niños. Danny 2015 is one of the more extreme examples of this. Enhanced TUTT activity would kill off anything that tries to make its way into the Caribbean/WATL though for obvious reasons, so the amount of real estate for a storm to develop and persist/strengthen in is limited. I believe Danny benefitted from being so compact, so it was able to take advantage of the window of favorability much easier than a larger system would.

[Category5Kaiju]

Could somebody please kindly remind me when the SPB is supposed to end?

[cycloneye]

Could somebody please kindly remind me when the SPB is supposed to end?

Here is all you want to know about the spring barrier.


Models have problems in predicting boreal winter tropical Pacific sea surface temperature when forecasts start in boreal spring (February–May). This is called the spring predictability barrier Similarly, “errors have the largest values and the fastest growth rates initialized before and during the Northern Hemisphere spring” .

https://www.climate.gov/news-features/b ... ring-break

[Category5Kaiju]

In about a week, it looks like there will be a formidable wall of westerlies blowing across the tropical Atlantic

[DorkyMcDorkface]

https://i.imgur.com/2lHSaj5.png

In about a week, it looks like there will be a formidable wall of westerlies blowing across the tropical Atlantic

If it were La Niña this would be grounds for forecasting a very active season (on top of the current warmth), but of course it occurs during the opposite so it's a mere question mark for now, lol

[JetFuel_SE]

https://i.imgur.com/2lHSaj5.png

In about a week, it looks like there will be a formidable wall of westerlies blowing across the tropical Atlantic

If it were La Niña this would be grounds for forecasting a very active season (on top of the current warmth), but of course it occurs during the opposite so it's a mere question mark for now, lol

I haven't used this site too often, so I probably got something wrong, but 1969 did also have a warmer than normal MDR at this time, along with a decently warm NIÑO 1+2.

[DorkyMcDorkface]

https://i.imgur.com/2lHSaj5.png

In about a week, it looks like there will be a formidable wall of westerlies blowing across the tropical Atlantic

If it were La Niña this would be grounds for forecasting a very active season (on top of the current warmth), but of course it occurs during the opposite so it's a mere question mark for now, lol

https://cdn.discordapp.com/attachments/1006712191522721812/1097411308405669938/t4814mTIup.png
I haven't used this site too often, so I probably got something wrong, but 1969 did also have a warmer than normal MDR at this time, along with a decently warm NIÑO 1+2.

You used it correctly, although I would use a different scale with more contours personally, just to better highlight some features.
Here's what ASO 1969 looked like:

[zzzh]

I would use 1951-1980 climo instead of 91-20. Also, that is AS, not ASO.

[DorkyMcDorkface]

:uarrow: I would use 1951-1980 climo instead of 91-20. Also, that is AS, not ASO.

Sorry, it is fixed.
As for the climo period, I cannot change that unfortunately. The site has 1991-2020 by default.

[zzzh]

[DorkyMcDorkface]

https://i.imgur.com/bkr3tQz.png

[Kingarabian]

https://i.imgur.com/2lHSaj5.png

In about a week, it looks like there will be a formidable wall of westerlies blowing across the tropical Atlantic

The ASW (or WAM?) is returning on the models and will be the strongest standing wave for the next 30 days. So it's playing a part in why there's going to be strong 850mb westerlies over the MDR.