Tracking the tropics - 2025

[WxWatcher007]

45 minutes ago, Diggiebot said:

Didn’t we just get a lesson in weenie range from Erin. Don’t even look at ops till inside 120 hours 

Yes. The ops are just fantasy but the ensembles show a pattern that could be conducive. Everything is always low probability for here so there’s no need for folks to get riled up. 

[Cyclone-68]

Do any of the other current tropical waves have a shot at the east coast or are they doomed to follow the Erin path again? Edit: or is it just too early to make that determination?

[CoastalWx]

22 minutes ago, Cyclone-68 said:

Do any of the other current tropical waves have a shot at the east coast or are they doomed to follow the Erin path again? Edit: or is it just too early to make that determination?

Cane season over. 

[Cyclone-68]

1 minute ago, CoastalWx said:

Cane season over. 

Yikes. I don’t feel this shot down since I asked Julie Adam’s to the prom 

[Great Snow 1717]

12 hours ago, ROOSTA said:

"TURN ON ANYTHING YOU'LL GET IT."
"THIS PLACE SURE GONE CRAZY."

This is the best hurricane tracking map to use...

[CoastalWx]

12 minutes ago, Cyclone-68 said:

Yikes. I don’t feel this shot down since I asked Julie Adam’s to the prom 

Alright maybe not over, but not sure much happens with Ferdy or whatver the name is.

[weatherwiz]

Erin taking a beating today 

[MJO812]

1 hour ago, CoastalWx said:

Cane season over. 

[CoastalWx]

49 minutes ago, weatherwiz said:

Erin taking a beating today 

Looked liie shit since late yesterday. 

[WxWatcher007]

I could see a TS watch for a place like Nantucket tomorrow given the wind field. 
 

56 minutes ago, weatherwiz said:

Erin taking a beating today 

Definitely. Shear and dry air taking a toll, though models try to restrengthen it some as it moves northward and maybe finds more favorable upper level winds. Everyone has struggled with Erin’s intensity forecast to an extent—upwards and downwards. Goes to show we still have a lot to learn. 

[weatherwiz]

6 minutes ago, CoastalWx said:

Looked liie shit since late yesterday. 

I see they upgraded to TS warnings for Cape Hatteras but the structure of Erin is getting destroyed and everything is essentially into the eastern quadrant of the storm. I know the wind field will expand and reconfigure as Erin grows but its entirely possible they barely get to TS force winds even to Cape Hatteras. 

[CoastalWx]

Yeah the euro has some nasty winds to Cape Cod. Decent pressure gradient will form as it moves north.

[weatherwiz]

8 minutes ago, WxWatcher007 said:

I could see a TS watch for a place like Nantucket tomorrow given the wind field. 
 

Definitely. Shear and dry air taking a toll, though models try to restrengthen it some as it moves northward and maybe finds more favorable upper level winds. Everyone has struggled with Erin’s intensity forecast to an extent—upwards and downwards. Goes to show we still have a lot to learn. 

Yeah we'll have to see if Erin either tries to re-strengthen some as it moves north or at least re-develops a better structure. But these two factors, particularly the later could have big impacts on what transpires across the outer banks of NC and even Nantucket. In addition to the shear and dry air you have to wonder if just sitting over the same area for so long is playing a factor too. 

It's even difficult to pinpoint the centers exact movement too. Almost looks like it could be more of a NNW heading but the center is also kind of jumping around a bit. 

 

[weatherwiz]

I also wonder if environment in the wake of Erin will be a bit too hostile for the follow up wave? Or at the very least wind shear may be unfavorable...GFS doesn't look great in this department. 

[WxWatcher007]

28 minutes ago, weatherwiz said:

I also wonder if environment in the wake of Erin will be a bit too hostile for the follow up wave? Or at the very least wind shear may be unfavorable...GFS doesn't look great in this department. 

Yeah it’s not looking good. I have my peak season forecast due tomorrow and I’m still not sure which direction I’ll go in. 

[CoastalWx]

Tropics are cancelled until further notice. I don't count a TS near the mid atlantic rift.

[MJO812]

22 hours ago, WxWatcher007 said:

Yeah it’s not looking good. I have my peak season forecast due tomorrow and I’m still not sure which direction I’ll go in. 

We need interesting weather

[MJO812]

24 minutes ago, CoastalWx said:

Tropics are cancelled until further notice. I don't count a TS near the mid atlantic rift.

Erin was so close to hitting the coast.  

[WxWatcher007]

42 minutes ago, CoastalWx said:

Tropics are cancelled until further notice. I don't count a TS near the mid atlantic rift.

If you think this is bad just wait until the AMO rubber band snaps back and we can't get a cloud swirl for 30 years.  

17 minutes ago, MJO812 said:

Erin was so close to hitting the coast.  

It wasn't close. A recurve was locked for days once we knew that trough in Canada wasn't going to be progressive. It's only the sheer size of Erin that makes it impactful. Still, at least we got enough of a trend to probably get some TS gusts at the coast. 

[weatherwiz]

10 minutes ago, WxWatcher007 said:

If you think this is bad just wait until the AMO rubber band snaps back and we can't get a cloud swirl for 30 years.  

It wasn't close. A recurve was locked for days once we knew that trough in Canada wasn't going to be progressive. It's only the sheer size of Erin that makes it impactful. Still, at least we got enough of a trend to probably get some TS gusts at the coast. 

Based off this morning, I am inclined to believe the track here on out will be towards the eastern edge of the cone. It took longer than I expected (mainly because the storm slowed to a crawl) but we're finally seeing the rapid shift north and northeast. 

 

[Diggiebot]

47 minutes ago, weatherwiz said:

Based off this morning, I am inclined to believe the track here on out will be towards the eastern edge of the cone. It took longer than I expected (mainly because the storm slowed to a crawl) but we're finally seeing the rapid shift north and northeast. 

 

Force field engaged 

[WxWatcher007]

Alright, here's my annual peak season forecast. If we have a chance, I think it has to line up with climatology. Either something short fuse that pops off in the SW Atlantic or a wave that gets picked up from the Caribbean by a trough in the next few weeks, or some sort of hybrid in the first third of October. Narrow window, but that's our climo. 

 

14 minutes ago, WxWatcher007 said:

August 20 is here, which means the bell has been rung. 

WxWatcher007 2025 Atlantic Peak Season Forecast

As a major hurricane churns off the east coast, we have reached the start of the peak of the hurricane season. So far, we've had 5 named storms, 1 hurricane, and 1 major...and one category five hurricane. 

The start of the season has been quiet, and while the general thought has remained that the season overall is likely to finish above average, my forecast looks at prime time. The background state of this season, unlike past years, has been quite hostile across the basin, but beneath the surface, conditions have been lining up for another active backloaded season. 

I define peak season as August 20-October 20, and this forecast covers that period. This is my 7th year writing such a forecast, and my record has been very good on balance, with the exception of one season.  

Seasonal Grades

2019 Grade: B+
2020 Grade: A-
2021 Grade: C
2022 Grade: B
2023 Grade: A
2024 Grade: B

Last year, we had a historically quiet first half of the peak season, with Ernesto forming on August 12th and no named system forming until Francine on September 9th. From there, all hell broke loose, with six additional hurricanes, three of them major, and two, Helene and Milton, being historic. 

This season it has been a struggle to get anything to survive in the basin, until Erin of course. The coming weeks likely bring a quiet period that may very well be reminiscent of last season. Then, the lid comes off.

ACE will flatline for a bit after Erin and the possible central Atlantic wave, but I think this year is shaping up to be another highly active second half peak. 

Peak Season Forecast (Aug 20-Oct 20)
Named Storms: 10 
Hurricanes: 6
Major Hurricanes: 3

As a reminder a typical season finishes at 14/7/3

Here are the major factors contributing to my forecast this season.  

1. ENSO

We start here and you always should. This year, ENSO favors activity. We are under a La Nina watch, so this is not the same kind of highly favorable regime that we had during our recent Nina stretch, but ENSO neutral conditions can still be very favorable. 

The 3.4 region has been cool neutral through the spring and summer, and if anything has cooled recently. This has big implications for the Atlantic basin, as a cool neutral ENSO brings many of the same impacts as a Nina, most notably, lower wind shear. 

(Image courtesy of Michael Lowry. Note the tracks as well) 

A cool neutral ENSO should bring us lower than normal wind shear in much of the basin during the peak, giving me confidence that we get a substantial number of hurricanes and major hurricanes, should they overcome some of the other obstacles in the basin. 

2. West African Monsoon

The WAM is a tricky beast. Last year, I think it running a bit hot led to some of the waves coming off Africa far too north, enhancing major stability issues and the SAL intrusions we saw in the tropical Atlantic.  

It was only in the last week or so that we started to see the wave train go, but it had a very different result from last year, with less SAL kicked up, though there has certainly been plenty of SAL out there in the basin. As the image below suggests, we will see above average precipitation across north Africa, which essentially serves as a proxy for the strength and persistence of the wave train.  

Shout out to CSU for putting me onto this longer range product. 

3. Wind Shear

This is a huge piece of what's going to determine the outcome of the peak forecast. As stated earlier, a non-El Nino season tends to have much less shear across the basin, and with a cool neutral ENSO it is highly likely that shear is less of an issue off the U.S. east coast and into the Caribbean. This has already proven to be the case as summer advances toward fall in the Caribbean and off the east coast. The tropical Atlantic, which I continue to believe will not be nearly as conducive for activity as it could be, has been the opposite. 

Although it is likely to be quiet during this period, you can see how deep layer shear becomes anomalously low across much of the basin as we move into the September high peak. I don't see a ton of anticyclonic wave breaking during the peak which would gut activity from the basin, but as we know, whether a wave develops and how much depends on in-situ shear often. Just knowing that the background state for shear will be favorable is more than enough for August 20. 

4. SST & OHC

I think the defining feature of this season will be the activity being concentrated in the SW Atlantic. Perhaps fortunately for my forecast, Erin kind of provides proof of concept. Erin came off the African coast as a robust wave, but ran into SAL to its north. Although that stunted its development for a few days, a warmer western Atlantic, low shear, and higher OHC led to explosive development. 

Sea surface temperature anomalies and ocean heat content were two major concerns I had going into this season, and for a while, it looked like it would greatly reduce potential. Erin's wake notwithstanding I think SSTs and OHC are now some of the chief reasons why I expect another high end peak. 

This analysis from Andy Hazelton sealed it for me. 

The pattern the last few years has remained fairly consistent in this forecast. The best conditions are west of about 60W, with higher OHC. This year we have SST anomalies in the mix, with the highest anomalies in the basin in record territory in the western Atlantic. 

Here was 2024 for reference. 

What a difference a year makes. 

Erin's wake will likely recover, especially considering how high OHC levels are in the southwest Atlantic. While the tropical Atlantic SSTs are running behind other recent historic years, that is not the case where it matters for impacts in our neck of the woods, with the Gulf and Caribbean untapped, and the SW Atlantic warmer than past years. 

 

OHC however, is where the real concern for higher end activity lies. Much like SSTs, in the tropical Atlantic the warmth is lower than in the Gulf and Caribbean. But look at the western Atlantic and the east coast in particular. 

 

It is the SW Atlantic where anomalies show that even in Erin's wake, there is plenty of heat there for any coastal storm that is close enough to take advantage of it. 

The bottom line is that the SST and OHC orientation is such that a high end peak is possible, especially in the western Atlantic, Caribbean, and Gulf. 

5. MJO & CCKW

The MJO and CCKWs that triggered the wave train have passed, and as we enter the peak of the season we are flipping to an unfavorable state in the basin. This alone should suppress activity as we are only at the beginning of the ramp up period for the peak. How long this lasts is TBD, and we have to keep in mind that while it may suppress MDR activity there are certainly short fuse named storms that could happen in a more favorable thermodynamic environment in the western Atlantic, western Caribbean, and Gulf. 

That said, things are likely to get quiet in terms of numbers, but the change is likely temporary. The MJO is expected to return on the second half of the peak. We saw last year that you don't need a lot of time to get the Atlantic to boil once the lid comes off. As the EPS suggests, we could start seeing favorable conditions return even earlier in the peak period, but I think a conservative expectation of things to heat up with the MJO after the 20th is the best route. That would make the September 20-October 20 period most active. 

6. Stability, Dry Air, and SAL

The final factor is perhaps the biggest in the early part of the forecast, and less so in the latter half as climatology takes over. It has actually been a lower end year for SAL in the basin, but once again the timing of SAL intrusions and peak climatology for SAL suppressed activity until Erin. Compare this to 2023 and 2024. Images courtesy of Michael Lowry. 

The recent wave train has helped clear the way to an extent for future waves, and although I don't expect a lot of development from the MDR in the coming two to three weeks, even waves that do not develop have the benefit of moistening the environment, just as our recent failed invest did, to pave the way for higher end activity. Even though there is SAL in the basin, it's not nearly as bad as it has been in recent years at this time in the tropical Atlantic. 

 

But SAL is only one part of this equation. We also have to look at base stability, which continues to be an issue in the eastern MDR. Vertical instability has been below normal for years in the eastern Atlantic, with instability improving the further west you go. This, like other years, is one of the biggest factors for believing the western Atlantic will be the hot spot. 

The east coast and Gulf have had extremely high levels of instability, which likely contributed to some of our early invests. 

Instability rises dramatically in September and October in the tropical Atlantic as climatology shifts and SAL reaches its nadir. I see no reason to question this again in 2025. As we saw in recent years, even if late August and early September are quiet due to a combination of SAL and stability, that lid still gets ripped off by late September provided an active wave train can moisten the environment. 

Overall

It may not start out hot (though I would watch the area in the central Atlantic for becoming the first NS/H for the peak period), but I expect another high end and backloaded peak season. The biggest piece of the puzzle--what the MDR SST and OHC profile would evolve into--has been answered, and it is high end again. None of this is normal, but that's the state that we have been in since 2017 in the Atlantic. An unfavorable MJO and declining climatology for SAL and stability in the eastern MDR will likely stunt high quantity activity through about mid-September, but things will likely reverse in a big way for the last 4-5 weeks of the peak season period. 

Unlike last season, I do not expect a lot of activity late into the season, like we saw last year in November. I think a less robust WAM will produce less waves by then that are able to cross the Atlantic, and a less favorable MJO by the time we get to very late October. 

Landfall Odds

I think a combination of ENSO, the active WAM, wind shear, instability, and SST/OHC will make the southwest Atlantic the hot spot this year. This is consistent with historical trends of a wet Sahel and moving from ENSO regimes. Images courtesy of Eric Webb. 

Note that the Gulf still gets storms, but I think this is a quieter year for that region. I think given what we've seen so far, and some of the long range steering pattern guidance (which is to be taken with a grain of salt), the central and eastern Caribbean, Bermuda, east coast, and Atlantic Canada--which is on a historic run of tropical cyclone landfalls--are most likely to be under the gun this season. 

I think there are a lot of recurves this season, but several threats for the region I highlighted. I think there is at least one east coast hurricane strike this year, and that we continue our streak of major hurricane strikes on the U.S. coastline.

Whether that means the east coast breaks its 21-year streak of no major hurricane landfalls, or New England breaks its 34-year streak of no hurricane landfalls (though I think the odd of this happening are substantially lower than the former) remains to be seen. 

If there is a New England strike, it would be something that comes from the Caribbean or a short fuse system in the southwest Atlantic, not a long track system. Ironically, the opposite would be true for a southeast coast--not including far eastern NC, which often gets scraped in a strike that ends in a landfall further north--with something developing east of the Antilles and getting trapped under a subtropical ridge. 

Thank you for reading. 

 

[Chrisrotary12]

When’s landfall?

[MJO812]

Its over

[Typhoon Tip]

Ha... Erin looks on satellite the last hour to be moving due E. 

Can you imagine if this were 1984?   You're all fluffed to the point of bursting over this hurricane set to rocket N in the modeling standard of the day, set to pummel the area ... replete with warnings and fever pitch.  Only to have set your coffee down this morning, and turned on the TV to a satellite loop of it moving due E   hahaha    priceless

That's what it was like in the 1980s ... the wah wah waahhhh decade.  Winter storms too.  

At least with this thing y'all mo'fuggahs knew ( though some stubbornly ignored...) 8 days in advance that the pattern was completely a piece of shit.