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

[Ntxw]

One good lesson learned this early season is that hot SSTs do not necessarily translate to big activity. This is actively being shown in the Atlantic and EPAC of reverse effect. EPAC is generating ACE with normal to below normal SSTA (Dora) while Atlantic is dealing with dry air and unfavorable winds, regardless of SST. It's the atmosphere that really is the determining player.

Suspect activity may pick up in the Atlantic once the hemispheric pattern cools and breaks down the stagnant trough-ridge pattern in the mid latitudes.

Isn’t the premise behind an active season despite an El Niño that warmer than normal ssts would lead to more rising air to counter the suppression caused by El Niño?

That can be a premise, and likely has played a role in muting some of the atmospheric response of ENSO CPAC not coupling, but one question is, much of the oceans is also experiencing this rise in heat, not just the Atlantic, so can one weigh more than the other? To what effect? I don't think we really understand it yet. I think in an island, the tipping balance might occur, but what happens when the weights are on all sides?

The real global budget lies in equatorial Africa to Indian Ocean and western Pacific and it hasn't pulled the forcing back to the MC, rather gradually moving east out into the Pacific.

[Woofde]

While that is true, the Atlantic is still anomalously warm, even compared to the global average anomaly. The chart below is even with cdas's notorious Atlantic cold bias. While el nino may be the grandaddy of climate indicators, we are talking about record breaking warmth in the Atlantic. With recent trends over the past few decades, the Atlantic has outpaced other basins with warming. There aren't any great analog years of our current setup. Its pretty telling when even the experts are split between average season or an extremely active one. It's a fascinating setup, we will get to see very soon which basin wins.

[SFLcane]

 https://twitter.com/AndyHazelton/status/1689328170338496525

[Spacecoast]

Today's extended range weekly shows ~10-20% chance of Tropical storms leading up to peak season...

[toad strangler]

Soon will be behind the ACE median. For those that care about that ... the long range MDR activity starting to show up on models would be right on time to turn that 2023 line up .... or in other words, the meat of the season is nearly upon us!

[SFLcane]

Thought id through this in this thread so everyone could see.

 https://twitter.com/AWxNYC/status/1689658425687347200

[cycloneye]

2 PM TWO being posted as the NHC is not working.

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 PM EDT Thu Aug 10 2023

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

Tropical cyclone formation is not expected during the next 7 days.

$$
Forecaster Berg

https://tgftp.nws.noaa.gov/data/raw/ab/ ... two.at.txt

[Category5Kaiju]

Thought id through this in this thread so everyone could see.

https://twitter.com/AWxNYC/status/1689658425687347200?s=20

Imagine a 21/11/5 season during a moderate El Nino. You can bet the wx community will go haywire once everything is done and complete

[WiscoWx02]

Thought id through this in this thread so everyone could see.

https://twitter.com/AWxNYC/status/1689658425687347200?s=20

Imagine a 21/11/5 season during a moderate El Nino. You can bet the wx community will go haywire once everything is done and complete

That would honestly be the last thing I would expect from this season as summer has progressed. 21/11/5 is something I personally doubt we’ll even get close to. Their low numbers 14/6/2 I would agree with though.

[WiscoWx02]

[tweet] https://twitter.com/andyhazelton/status ... JB87dhNSqw[/tweet]

Still got a ways to go till we see anything try to get going in the MDR imo.

[Keldeo1997]

 https://twitter.com/DerekOrtt/status/1689856943785938944

[cycloneye]

 https://twitter.com/AndyHazelton/status/1689993407639207936

[Hurricane2022]

https://twitter.com/AndyHazelton/status/1689993407639207936

El Nino!

[Woofde]

Something interesting in the SST profile I'm noticing is how far Northeast the warmth extends. I wanted to see if there was any correlation, so i looked through recent analogs to about 1990. There aren't many similar analogs with far reaching warmth, but the closest ones I could find are 2019, 2012, and 2004. Notably each of these seasons featured numerous storms in the East, atleast 4. Intestingly you can see the opposite effect if you look at seasons with low eastern warmth. 2011, 2007 and 2000 all had low levels of warmth in the Northeast, each of these seasons featured practically no activity there. I'm thinking we are going to see increased activity in the Eastern part of the Atlantic. Now I know this might seem like a fairly obvious thing, and you might be saying "well duh warm ssts = more storms", but I wanted to bring it up because it gives more credibility to the idea of an above average season. An extra 2-3 storms and maybe an extra hurricane or 2 from having a larger basin area in play would inflate season totals a bit.

[869MB]

Something interesting in the SST profile I'm noticing is how far Northeast the warmth extends. I wanted to see if there was any correlation, so i looked through recent analogs to about 1990. There aren't many similar analogs with far reaching warmth, but the closest ones I could find are 2019, 2012, and 2004. Notably each of these seasons featured numerous storms in the East, atleast 4. Intestingly you can see the opposite effect if you look at seasons with low eastern warmth. 2011, 2007 and 2000 all had low levels of warmth in the Northeast, each of these seasons featured practically no activity there. I'm thinking we are going to see increased activity in the Eastern part of the Atlantic. Now I know this might seem like a fairly obvious thing, and you might be saying "well duh warm ssts = more storms", but I wanted to bring it up because it gives more credibility to the idea of an above average season. An extra 2-3 storms and maybe an extra hurricane or 2 from having a larger basin area in play would inflate season totals a bit.https://uploads.tapatalk-cdn.com/20230811/b91d6bc424959693c27342b46991236d.jpg https://uploads.tapatalk-cdn.com/20230811/a7914ad469245f2d1907ee28d23fcc4b.jpg

Great points. And of course another argument going the other direction can be made, with a supposedly strengthening El Niño inducing increasingly unfavorable conditions, especially over the Southern Gulf of Mexico and Caribbean Sea and eventually the SW Atlantic, as the hurricane season progresses would theoretically shave off a storm or three that would have otherwise developed under more favorable ENSO conditions. Also, you can see the stout -PDO increasingly shrinking as time progresses, so it remains to be seen what, if any, effects these warming waters will have on the Atlantic Hurricane Season before all is said and done.

So maybe when November 30th arrives, the storm total numbers will be slightly increased across the Eastern portions of the Atlantic basin while in the Caribbean/Southern Gulf, storm totals will be slightly lower.

[tolakram]

Putting this hear because it's a seasonal observation.

This seasons equation seems pretty simple to me. The western MDR will rip up storms all year, but anything outside of this unfavorable zone will be able to take advantage of the way above normal conditions. Will anything be there to take advantage of these conditions? Even in el nino years there's still plenty of areas of good conditions for storm formation, but there needs to be a spark. So this year the odds are higher, but it's far from a sure thing.

As far as shear forecasts go, here's the Aug 5th 0Z GFS shear map run for today:



Euro:


Current tendency (using this map because the colors make for an easier comparison)


source: http://tropic.ssec.wisc.edu/real-time/windmain.php?&basin=atlantic&sat=wg8&prod=sht&zoom=&time=

Not a horrible guess from either model in the 168 hour timeframe. Euro doesn't go much further but take any run past 200 or so hours and you will notice the entire basin fills with shear. Upper lows all over the place, hardly any areas of good conditions. I think this is artifacts of the models, not reality. We'll see, but I'm not buying el nino is suddenly going to turn on and prove everyone wrong. Of course I'm also not buying an above normal year. A normal year in what should be a below normal el nino year sounds about right to me.

[gatorcane]

Looking at the WV loop this evening, quite a bit of westerly winds pushing all of the clouds over the United States towards the east and we can see the Bermuda High is squashed more to the south with a ridge axis over Florida. The westerlies are basically almost to Florida as short-wave after short-wave moves east and off the US coastline. This has pretty much been the story this summer so far and El Niño is likely the reason. It is entirely possible the pattern will only become more pronounced as we head into September and especially October and as El Niño strengthens:

[zzzh]

Western MDR won't be sheared all year.

[cycloneye]

To let the peeps know that Dora has moved to the West Pacific basin, exploring it and now is Typhoon Dora.

[Ianswfl]

Looking at the WV loop this evening, quite a bit of westerly winds pushing all of the clouds over the United States towards the east and we can see the Bermuda High is squashed more to the south with a ridge axis over Florida. The westerlies are basically almost to Florida as short-wave after short-wave moves east and off the US coastline. This has pretty much been the story this summer so far and El Niño is likely the reason. It is entirely possible the pattern will only become more pronounced as we head into September and especially October and as El Niño strengthens:

https://i.postimg.cc/kgHdxCGM/goes16-wv-mid-nwatl.gif

Early June was cooler here in SWFL with more clouds. I lived in Naples in 1998 and remember it being a very dry and warm summer with the storms staying inland. This is helping our water temps soar. I suspect there will be breaks now until sept with this pattern. I imagine we will get a stretch.

Looking at the long range models for next spring all of them show above normal water temps in most of the Atlantic including the Gulf. So post El Nino could be a very active season next year!