Biggest underperformers and overperformers

[zhukm29]

Lee is 100% an underperformer---no doubt about it. HAFS models expected it intensify to 170-180 knots, yet it only reached a measly 145 knots.

"Only" 145 kts. I feel you put your expectations way too high. You got a Cat 5 and you're still complaining.

Yeah a feat not even 2020 officially could pull off! But yeah all is relative I guess, with many expecting a Haiyan out of this thing like the models showed once Lee really took off. Definitely not an underperformer, more like performed as expected originally.

Lee is not an underperformer, period. I feel like we've all been spoiled by the past few years that a 145kt explosively intensifying Cat 5 could even be considered an underperformance.

It wasn't too long ago that we nearly went a decade without a single Category 5 in the Atlantic (officially, Felix 2007 -> Matthew 2016). Category 5 is not a guaranteed occurrence either even in perfect conditions, due to other factors such as ERCs, etc., so IMO any storm that manages to reach Cat 5 is not an underperformer.

[Hurricaneman]

Dorian in 2019 was only expected to get to 45mph on the first advisory but ended up being one of the strongest hurricanes on the Atlantic not in the Caribbean or GOM

[FireRat]

Lee is apparently getting pretty pissed

[Ubuntwo]

Lee is 100% an underperformer---no doubt about it. HAFS models expected it intensify to 170-180 knots, yet it only reached a measly 145 knots.

The same HAFS that brought Franklin to 160kt? They're still experimental models and, it should be said, the only guidance that brought Lee to those soaring heights. By all other metrics Lee overperformed.

[Ubuntwo]

Erika worth a mention in the 'underperformer' category...

[xtyphooncyclonex]

Dorian was forecast to hit the Bahamas as a tropical storm. We all knew how that turned out.



Dora was quite the opposite of Lee this year, being forecast to weaken to a category 1-2 several times but instead stayed at Cat 4 for a whopping 146 nonconsecutive hours --- the EPac record longest.

[dexterlabio]

From the Western Pacific

Underachiever: Kammuri (2019) - victim of strong shear that popped out of nowhere

Overachiever: Noru (2022)

[Woofde]

Lee is 100% an underperformer---no doubt about it. HAFS models expected it intensify to 170-180 knots, yet it only reached a measly 145 knots.

"Only" 145 kts. I feel you put your expectations way too high. You got a Cat 5 and you're still complaining.

Yeah a feat not even 2020 officially could pull off! But yeah all is relative I guess, with many expecting a Haiyan out of this thing like the models showed once Lee really took off. Definitely not an underperformer, more like performed as expected originally.

Poor Iota, I still can't believe they hit it with that postseason downgrade.

[xtyphooncyclonex]

From the Western Pacific

Underachiever: Kammuri (2019) - victim of strong shear that popped out of nowhere

Overachiever: Noru (2022)

Kammuri definitely struggled so much... could have lasted days as a cat 3+ if not for the shear. But that ramped up so quick right before Sorsogon.

Noru was such a surprise. No one would've thought that tiny thing would not just go way farther south, but hit category five right before landfall.

I'd also like to add Rai which made me rethink tracking storms myself. Everyone was expecting a cat 1-2 hit over VisMin and it exploded overnight into a 150-kt monster. Definitely demonstrated the PH Sea effect

[aspen]

Haven’t seen Larry ‘21 or Earl ‘22 mentioned yet. Both could’ve become Cat 4s, but due to internal dynamics, they maxed out as a 3 and a 2, respectively. I remember Larry kept trying to undergo an EWRC with like a 100 mile wide outer eyewall.

Ian was a huge over-performer comparable to Michael. At first it seemed like shear would keep a lid on it, but it managed to get oriented just right for the shear to ventilate it instead. There were a lot of model runs that took it further north into the Gulf where shear ripped it apart, but it stayed further south and was able to intensify.

[dexterlabio]

From the Western Pacific

Underachiever: Kammuri (2019) - victim of strong shear that popped out of nowhere

Overachiever: Noru (2022)

Kammuri definitely struggled so much... could have lasted days as a cat 3+ if not for the shear. But that ramped up so quick right before Sorsogon.

Noru was such a surprise. No one would've thought that tiny thing would not just go way farther south, but hit category five right before landfall.

I'd also like to add Rai which made me rethink tracking storms myself. Everyone was expecting a cat 1-2 hit over VisMin and it exploded overnight into a 150-kt monster. Definitely demonstrated the PH Sea effect

I distinctly remember the models showing an intense cat5 hitting the Philippines days before Rai formed. It was just that the environment was looking too hostile and many people were thinking that it was just the models being bullish. But then Rai pulled off an ERI just like the models predicted, and the rest was history.


Here are the other storms that stuck to my memory for overachieving/underachieving

ATL
Danny and Joaquin 2015 (overachievers)
Humberto and Ingrid 2013 (underachievers)

WPAC
Vicente 2012 (overachiever- was forecast to stay as a weak to moderate TS but it suddenly developed an eye prior to landfall in China; made landfall as Cat4)

[doomhaMwx]

Overperformer: Mujigae (2015)
It was expected to hit Southern China as a category 1 typhoon but ended up RI'ing to a 115kt category 4 just within 12 hours before landfall. The attached images were JTWC's forecasts 24 hours and 12 hours before landfall.

[ChrisH-UK]

For this year TC Freddy was only expected to be a Cat 3 at first but then went to cat 5 and kept going and going and going. Eventually when it did made landfall in Madagascar after traveling from near Indonesia it reformed at hit Mozambique then came back out and hit Madagascar again and then Mozambique for the second time Freddy.

I think Freddy is the most overperforming TC of all time, with the longest lasting TC and the most ACE of any TC.

[doomhaMwx]

WPAC trackers will not forget how this pair in 2020 turned out: Goni (overperformer) and Atsani (underperformer).

Early model and agency forecasts for Goni weren't impressive. JTWC's first forecast was 90kt while JMA only initially expected a minimal typhoon. Nobody expected that we would be looking at a 170kt, Haiyan-level monster striking the Philippines a few days later.




On the other hand, models (even the usually bearish Euro) were so aggressive with Atsani that we thought it was going to be the highlight of the 2020 Typhoon Season. It ended up being a mere tropical storm . It might actually be the biggest underperformer I have ever witnessed.

[ThunderForce]

I feel like Michael is an example of a hurricane that overperformed expectations. Initial NHC guidance was calling for it to be a tropical storm at landfall, but then the guidance said it would be a Category 1 later the same day. Later still it was stated it would be a 2 at landfall, and then 3, followed by 4... It just kept ramping up and up beyond the guidance. By the time it made landfall, it was a Category 5 and still didn't seem to have hit it's peak before weakening due to interaction with land.

[Hammy]

Humberto in 2007 was both an overperformer and highlights a dangerous situation that can occur: was forecast to come in at 40kt and moved onshore a mere 16 hours later at double that intensity, with a very well defined core taking shape as it was making landfall.

[al78]

Underperformers:

Hurricane Debby 2000. I vaguely remember concerns that it could approach southern Florida as a category 4 hurricane, in reality it peaked as a cat 1 then fell apart from land interaction with the Greater Antilles.

The 2007 hurricane season. A strong La Nina, two cat 5 hurricanes, yet the overall picture looked more like an El Nino year with an early shutdown with virtually nothing developing in October (why?) and a below average ACE. The unusual lack of late season activity during a La Nina event was repeated recently in the 2021 hurricane season (again what happened?).

Overperformers:

Hurricane Celia 2010, From the discussions:

800 AM PDT WED JUN 23 2010

WHILE ALL OF THE INTENSITY SHOWS SOME
STRENGTHENING OVER THE NEXT 24 TO 36 HOURS...NONE OF THE MODELS
MAKE CELIA A MAJOR HURRICANE.

800 AM PDT THU JUN 24 2010

NONE OF THE INTENSITY GUIDANCE SHOWS ANY STRENGTHENING OF
CELIA...AND THIS APPEARS SOMEWHAT UNREALISTIC GIVEN THE VERY
FAVORABLE UPPER-LEVEL WIND PATTERN AND RELATIVELY WARM WATERS THAT
CELIA IS OVER AT THE MOMENT.

800 PM PDT THU JUN 24 2010

SATELLITE IMAGES INDICATE THAT CELIA HAS RAPIDLY INTENSIFIED DURING
THE PAST SEVERAL HOURS.

Hurricane Charley 2004 and its rapid intensification from cat 2 to cat 4 just hours before landfall in SW Florida.

[Category5Kaiju]

Underperformers:

Hurricane Debby 2000. I vaguely remember concerns that it could approach southern Florida as a category 4 hurricane, in reality it peaked as a cat 1 then fell apart from land interaction with the Greater Antilles.

The 2007 hurricane season. A strong La Nina, two cat 5 hurricanes, yet the overall picture looked more like an El Nino year with an early shutdown with virtually nothing developing in October (why?) and a below average ACE. The unusual lack of late season activity during a La Nina event was repeated recently in the 2021 hurricane season (again what happened?).

Overperformers:

Hurricane Celia 2010, From the discussions:

800 AM PDT WED JUN 23 2010

WHILE ALL OF THE INTENSITY SHOWS SOME
STRENGTHENING OVER THE NEXT 24 TO 36 HOURS...NONE OF THE MODELS
MAKE CELIA A MAJOR HURRICANE.

800 AM PDT THU JUN 24 2010

NONE OF THE INTENSITY GUIDANCE SHOWS ANY STRENGTHENING OF
CELIA...AND THIS APPEARS SOMEWHAT UNREALISTIC GIVEN THE VERY
FAVORABLE UPPER-LEVEL WIND PATTERN AND RELATIVELY WARM WATERS THAT
CELIA IS OVER AT THE MOMENT.

800 PM PDT THU JUN 24 2010

SATELLITE IMAGES INDICATE THAT CELIA HAS RAPIDLY INTENSIFIED DURING
THE PAST SEVERAL HOURS.

Hurricane Charley 2004 and its rapid intensification from cat 2 to cat 4 just hours before landfall in SW Florida.

The one thing I do know about 2007 is that the season saw an Atlantic that was much colder compared to normal (see past sst anomalies maps). I also vaguely remember wx people talking about how 2007 and 2021 saw an early shutdown due to some trough or jet stream dipping down by October? Can't recall exactly though

[Teban54]

The primary reason for 2021's late-season shutdown was the strong Atlantic Nino, which dragged the ITCZ further south. So instead of waves being sent into the Caribbean like 2020, they crashed into South America without development on the Atlantic side, and ended up developing after they reach EPAC and becoming Pamela, Rick, etc.

[Hurricane2022]

Flopicane Nigel is an underperformer!

The depression is forecast to gradually intensify over the next
couple of days as moderate northeasterly shear and the initial broad
cyclone structure could provide a check on the intensification
rate. By early next week, this system is forecast to move over
near record warm sea-surface temperatures for the region in light
shear conditions. It probably sounds like a broken record at this
point in the season, but rapid intensification is a significant
possibility, and the official forecast could be conservative below.
The intensity forecast is near or above the intensity consensus,
only leveling off at 120 hours due to gradual SST cooling and the
possibility of eyewall replacement cycles, as suggested by the HAFS
model suite.

FORECAST POSITIONS AND MAX WINDS

INIT 15/1500Z 14.4N 43.8W 30 KT 35 MPH
12H 16/0000Z 15.5N 44.7W 35 KT 40 MPH
24H 16/1200Z 17.2N 46.0W 40 KT 45 MPH
36H 17/0000Z 18.9N 47.9W 50 KT 60 MPH
48H 17/1200Z 20.5N 49.6W 60 KT 70 MPH
60H 18/0000Z 22.0N 51.2W 70 KT 80 MPH
72H 18/1200Z 23.4N 52.9W 85 KT 100 MPH
96H 19/1200Z 26.0N 56.8W 105 KT 120 MPH
120H 20/1200Z 29.0N 60.0W 100 KT 115 MPH