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

[captainbarbossa19]

Seems like Fred and Grace, instead of ending the season cancel talks, have only added more fuel to the fire — persistent MDR shear, shredder tracks being favored, the reluctance of the MJO to move to Phase II, and the EPac being able to produce a strong hurricane while the supposedly favored Atlantic is struggling to get anything of significance. I don’t see how shredder tracks will be the only tracks MDR storms would take this year; that’s quite a thin strip of latitude for every MDR storm to hit, and it would require a very specific and unchanging ridge setup to keep it happening.

Extrapolating the last week out to the rest of the season presents quite a season cancel prediction: the African monsoon shearing anything in most of the MDR, but nothing can recurve and it instead heads into the shredder to never develop. However, extrapolating a short-term trend to judge the next 2-3 months is foolish, as a developing Nina will likely lead to development focusing to the Caribbean and Gulf instead of the MDR by October. Also, it is impossible for the MJO to remain in one place for months.

Right. People forget that it is right now August 13. As mentioned earlier, not a single major hurricane has developed in the Atlantic before August 20th since 2009. Even 2015 managed to produce a major hurricane around peak-season despite obstacles.

Also, having weak storms in mid-August is not unusual. Remember how Harvey opened into a tropical wave in 2017? That happened on August 19! Within a few days, Harvey redeveloped into a major hurricane. I do not think that this will happen with any systems out there now, but the point is that conditions can quickly go from hostile to favorable.

[AxaltaRacing24]

Like I said earlier, we have had an above average season each year since 2016. Two of those (2017 and 2020) were hyperactive. ZERO had a major before 8/20. It is 8/13…..

[AlphaToOmega]

We are in Phase II. Phases I-IV favor Atlantic tropical activity. Nothing is expected to form in the East Pacific within the next five days. The GFS shows no East Pacific development within the next ten days. People who live in hurricane-prone areas should have prepared themselves by now, for tropical activity is likely to occur exclusively in the Atlantic for the next couple of weeks.

[Category5Kaiju]

I feel like it's a fairly simple but oftentimes overlooked idea (which is also pretty significant), but let me put it this way: it is mid-August. While there are those who equivalate both scenarios as a strong warning sign of a season cancel, complete bust season, seeing absolutely none, zero named storms versus seeing several (albeit weak) NSs imho is quite the major difference, with the latter suggestive of more favorable conditions than the former by nature.

[NDG]

I remember this same time in 2017 talking about having the same season cancled conversations and then all hell broke loose just a few days later.

[galaxy401]

At this point in 2010, the season was only at 3/1/0. It would remain that way until after August 20. The season ended with 19/12/5. I remember there were a ton of season cancel posts that year.
2018 was 4/2/0 at this point with the 6th named storm not forming until August 31. The season ended with 15/8/2.

I know this has been repeated multiple times on this page alone but early August is still an unfavorable period for the Atlantic. It's literally a continuation of June and July. August 20 is the switch. If we get to the start of September and the pattern still looks very unfavorable with poor model support then I will start getting skeptical. Even then, models are slow to pick up on storms in recent years.

I don't know what's going on with the MJO but the MDR is waking up now.

[Chris90]

The MJO is starting to move into the Atlantic, with -VP anomalies spreading across Africa into the Indian ocean, but greatest amplification seems to be south of the equator, at least for now. If the EPAC is any indicator with the tc activity there over the past couple weeks, it might take a couple weeks before the ATL really gets going (which lines up with the August 20th bell ringing). The EPAC is only now starting to flex again after Felicia with Linda now putting on a show as the MJO moves out. The storms between those 2 were... messy.
The Atlantic still has the opening acts on stage, once they finish their set the headliners will come out for the main show.

[SoupBone]

I remember this same time in 2017 talking about having the same season cancled conversations and then all hell broke loose just a few days later.

Let me see if I can post this correctly. There is a difference in quality versus quantity, as we see in ACE numbers versus the number of forming systems. This season may very well be one of those that generate crappy systems, but plenty of them. Time will tell. People might be meaning that type of season versus a true cancel, which is definitely absurd in mid-August.

[AxaltaRacing24]

I remember this same time in 2017 talking about having the same season cancled conversations and then all hell broke loose just a few days later.

Let me see if I can post this correctly. There is a difference in quality versus quantity, as we see in ACE numbers versus the number of forming systems. This season may very well be one of those that generate crappy systems, but plenty of them. Time will tell. People might be meaning that type of season versus a true cancel, which is definitely absurd in mid-August.

It could be, but that isn't likely with the background state. The 6/1-8/19 pregame show in this basin is easy to fool people into thinking that could happen, but time and time again in La Nina or cool neutral years, the quality systems come in plenty after late August begins.

[caneseddy]

To add to this, most major hurricanes that have impacted the US mainland formed in late August-September. Below are some famous storms that formed during this timeframe to name a few

1. 1935 Labor Day (formed August 29)
2. Hugo (September 9)
3. 1926 Miami Hurricane (September 11)
4. 1928 Lake Okeechobee (September 6)
5. Irma (August 30)
6. Floyd (September 7)
7. Ivan (September 2)
8. Katrina (August 23)

Yes what we are having now are not impressive storms, but there is a reason the "ringing" of the bell is August 20. Just give it a couple more weeks.

[tolakram]

Once again we have more posts about season cancel posts than actual posts about season cancel. Let's stick to indicators please.

[EquusStorm]

Happens every year. People will foolishly cancel the whole season based on perfectly normal marginal activity in the perfectly normal marginal to unfavorable climo of the early to mid August stretch, and as the Atlantic heads towards its seasonal peak and becomes active, they will be proven wrong just as they are almost every single year. The Aug/Sep/Oct peak isn't so much Aug 1 to Oct 31 as it is Aug 20-25 to late October; early August tends to be very boring with significant hurricanes being rare exceptions rather than the rule. One reason I try very hard to stay away from seasonal indicator threads.

Background state is good, still running with the top six or seven years of activity all time with some of the earliest named storms on record by letter, earliest MDR hurricane since 1933, longest lived July storm since 2008, first Caribbean July hurricane since 2005 which even 2010 and 2017 couldn't pull off, experts forecasting a very active season, cool neutral to Niña with less dust than last year (the most active season on record despite it) and significant wave activity on models much more aggressive than this time last year - y'all ain't patient

[AlphaToOmega]

The CanSIPS and JMA both forecast the most favorable possible pattern for Atlantic hurricane seasons: rising air over Africa and the Indian Ocean, sinking air over the East Pacific and the Americas, a positive Tropical North Atlantic index, a positive Atlantic Multidecadal Oscillation index, a negative El Niño Southern Oscillation index, a negative Pacific Decadal Oscillation index, and a negative Indian Ocean Dipole index. This exact was seen only in 2020 and 2010. All major indicators point to a hyperactive season; anything that might hinder this hurricane season is just intra-seasonal variation.

2010 underperformed as a hurricane season due to a large amount of dry air during the peak season. 2020 had the Godzilla Dust Storm, which hindered tropical activity for a while. 2021 is encountering neither of those issues nearly as much as 2010 or 2020. All of this is to say that 2021 is very likely to be hyperactive (>159 ACE), and it could still rival record-breaking seasons such as 2020, 2005, and 1933. May and June were active, but July was inactive; but the early season is a terrible bellwether period; and August and September seem to be very favorable for tropical development. October still seems favorable for tropical development.

Unless there is something that could make this hurricane season near-average or below-average (something that could override the favorable SST and rising air setup) or unless the CanSIPS and JMA bust harder than the 2013 Atlantic Hurricane Season expert forecasts, it seems like a near certainty that the 2021 Atlantic Hurricane Season will be hyperactive.

[Category5Kaiju]

Happens every year. People will foolishly cancel the whole season based on perfectly normal marginal activity in the perfectly normal marginal to unfavorable climo of the early to mid August stretch, and as the Atlantic heads towards its seasonal peak and becomes active, they will be proven wrong just as they are almost every single year. The Aug/Sep/Oct peak isn't so much Aug 1 to Oct 31 as it is Aug 20-25 to late October; early August tends to be very boring with significant hurricanes being rare exceptions rather than the rule. One reason I try very hard to stay away from seasonal indicator threads.

Background state is good, still running with the top six or seven years of activity all time with some of the earliest named storms on record by letter, earliest MDR hurricane since 1933, longest lived July storm since 2008, first Caribbean July hurricane since 2005 which even 2010 and 2017 couldn't pull off, experts forecasting a very active season, cool neutral to Niña with less dust than last year (the most active season on record despite it) and significant wave activity on models much more aggressive than this time last year - y'all ain't patient

The way I see it, this year is no different from the other active past years with a favorable background yet still did not produce significant storms in early-mid August and prompted individuals to doubt the season during that time. It's almost like the boy who cried wolf. Now if a season does happen in the future that completely defies expectations of being very active despite an otherwise favorable looking background (in other words, another 2013), then I will owe an apology to the season doubters. However, I just don't know when that will be, and even if the chances of such occurring are considerable. Anyways, back to indicators.

[EquusStorm]

Eh? 2010 was a hyperactive season with near record activity at peak season, with twelve hurricanes tying for second most on record in a single season, five majors, and a near record five October hurricanes. It started very late and steering patterns kept things from hitting the US but it was certainly an overperformer, tied for third most on record at the time.

If we had ridging like is currently now covering the basin back in 2010 it'd certainly be a much different story when it comes to how quiet the season was perceived in the US. Earl and Igor would not have been welcome visitors.

[gatorcane]

The EPAC on the long-range GFS continues to look slow. Atlantic should be turning more active as we head into the second half of August. Bell rings Aug 20th…

[toad strangler]

The EPAC on the long-range GFS continues to look slow. Atlantic should be heating up as we head in the second half of August. Bell rings Aug 20th…

Yup

RIP Dr. Gray!

[cycloneye]

New IMME has an active Atlantic thru ASO.

 https://twitter.com/webberweather/status/1426394365719576584

[Hammy]

New IMME has an active Atlantic thru ASO.

https://twitter.com/webberweather/status/1426394365719576584

My understanding of this is very new so genuine question: what is the mechanism here that favors an active Atlantic with large subsiding air over most of the basin?

[AlphaToOmega]

New IMME has an active Atlantic thru ASO.

https://twitter.com/webberweather/status/1426394365719576584

My understanding of this is very new so genuine question: what is the mechanism here that favors an active Atlantic with large subsiding air over most of the basin?

The IMME shows rising air over Africa, the Indian Ocean, and the Maritime Continent. The rising air over those regions creates humid air conducive for tropical wave formation, and, once they reach the Atlantic basin, they become tropical cyclones.