Discussion of Intense Tropical Cyclones

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Re: Discussion of Intense Tropical Cyclones

#621 Postby rileydoxsee98 » Mon Apr 19, 2021 10:18 am

aspen wrote:
rileydoxsee98 wrote:
aspen wrote:Bumping this thread up for Cyclone Niran.

Pinhole eye, full CDG ring...you don’t get much more Cat 5 than this. If Niran holds this look, there would be an argument for a 155+ kt storm.
https://rammb-data.cira.colostate.edu/tc_realtime/products/storms/2021sh23/4kmsrbdc/2021sh23_4kmsrbdc_202103051100.jpg




Yeah Niran had a really impressive CDO. However, it’s eye and it’s inner structure is poor. Niran had a double eye wall and it’s cloud tops was likely enhanced by the typical SPAC tropopause, Niran only has an OW eye. It’s clearly a T7.0. But this is a case where a T7.0 in my opinion likely isn’t a Category 5. The reason this is because the eye was pretty ragged and cold for its intensity, I don’t buy into the theory of the SPAC having bad eyes because the top end monsters there such as Hina, Nisha, Olaf, Winston didn’t have any problems with their eyes, plus the WPac often gets just as cold convection and doesn’t have problem with eyes. Imo the tropopause of the SPAC just masks a bunch of issues that the cloud tops appear to be hiding. I actually strongly doubt Niran was a Cat 5 in reality, it’s eye was pretty bad for a T7.0 and it had shear affecting it+ double eye wall structure. Very reminiscent of Hurricane Eta, which only reached official Final Ts of 6.5-7.0 and the recon observation is actually not far off from the Dvorak. But if anything I think Niran was WEAKER than Eta. I estimate Niran at 130knots/921mb. A lot of people have called me a low baller and a downcaster for my Niran estimates but that’s just my opinion. Very deep convection and bad eye, to me that indicates it’s hiding something that is being masked by the cloud tops.

Also, it wasn’t able to hold on to or improve its IR appearance for long, so if it was undergoing ERI, the winds likely did not have enough time to catch up to its structure.



Yeah. Good point. My estimate may seem too low and in reality it may be. But if Niran was a 5 I have doubts it was above 140kts. I went 130kts because SMAP indicated 120-125kts and Dvorak indicated 140kts. I had 135kts originally but I downgraded Niran to 130kts recently because of the poor inner core structure. But I totally understand why some would keep Niran as a Cat 5, cause it did hold onto DTs of 7.0 for like 18
Hours if I recall correctly.
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Re: Discussion of Intense Tropical Cyclones

#622 Postby Shell Mound » Thu Apr 22, 2021 7:46 am

supercane4867 wrote:
1900hurricane wrote:Another thing worth pointing out is the storm selection that was used was somewhat limited. Some lesser-known C5 TCs from other basins or even "missed" C5 TCs were excluded from the study. I feel like the SPac in particular was underrepresented. Using only C5 TCs, and not even the entire selection of the available ones confined the scope of the study somewhat.


I'm quite perplexed about how they left Hina 85 out of their study. There were also plenty of other noteworthy TCs in the SPAC that could have been included in the study.

https://i.imgur.com/JDA3sgc.png
https://i.imgur.com/XNQvUxI.jpg

Do you have the links to the original sources of these satellite images? I am also looking for DVORAK data from as many basins as possible back to the late 1970s.
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Re: Discussion of Intense Tropical Cyclones

#623 Postby dexterlabio » Fri Apr 23, 2021 7:26 pm

1900hurricane wrote:
InfernoFlameCat wrote:The most impressive typhoon, Typhoon Tip, became the largest tropical cyclone. Why was is so large? Storms that large are almost always near ex-tropical yet Tip was at its peak when it was its largest. I mean, that storm was absolutely insane.

I think Tip's origins and intensification environment had a profound effect on its evolution leading up to peak intensity. Tip developed on the eastern end of an active monsoon trough, and at first, it had to share the monsoon trough with Tropical Storm Roger to the west. Roger quickly lifted poleward and out though, giving Tip access to the entirety of the monsoon trough without any competition. In response, the consolidating Tip developed a large circulation. I think this setup is somewhat similar to that of Super Typhoon Lan from 2017, another system that had unrestricted access to the entirety of an active monsoon trough. Given such a large circulation in these two cases, it would take several days with near ideal conditions for the system to properly consolidate. That wasn't an issue for Tip though, which moved slowly and occasionally erratically to the WNW over the warm fertile waters east of Guam. This is in sharp contrast to Lan, which was captured by a passing mid-latitude trough and pulled poleward into the subtropics just before reaching maturity. It took three days for the sprawling circulation of Tip to fully consolidate a core during the period of undisturbed development from October 7th to the 10th, but once complete, it began its first episode of rapid intensification on October 10th. Below, you can see Tip consolidating early in its development phase on October 7th and 8th, respectively.

https://i.imgur.com/TwOnqxT.jpg

https://i.imgur.com/7Wur6aE.jpg

Something else I think needs further discussion when referring to Tip's size record is how size of tropical cyclones is actually measured. Should size be measured by the radius of tropical storm force winds? Would the radius of the outermost closed isobar be better? How about overall cloud footprint? In the Tip report by Dunnavan & Dieicks, it makes mention on the first page that the oft-cited Tip size record of a 2220 km diameter (radius of 1110 km/600 nm) is measured using the highest/outermost closed isobar of the system. Using the 20th Century v3 data, I arrived at at almost the exact same size for the pressure field. This is a pretty common measurement for tropical cyclones, particularly of that time. However, this is different than the diameter of TS winds, which is perhaps a more common way to convey tropical cyclone size today. In fact, the way the WMO recognizes Tropical Storm Marco from 2008's small size record is by the TS wind radius, creating a notable disconnect between the two records.

https://i.imgur.com/tAMT6aE.gif

That's not to say Tip's size wasn't noteworthy. A correlation definitely exists between the size of the outermost closed isobar and TS wind field in mature TCs. In fact, aircraft recon mission 26 into Tip reported exceptionally large storm and typhoon wind radii when reducing from a 700 mb flight level. However, that record needs to be looked at with a skeptical eye for sure given some of the different ways TC size can be measured. Both recon and satellite data (SMAP pass below) indicated Tedward in 2020 had larger wind radii than even Tip's mission 26 just before it finished extratropical transition. Also, when examining the td9635 Typhoon Analog dataset, which kept record of tropical cyclone size using the diameter of the outermost closed isobar in degrees latitude in 1976 and prior, larger TCs than Tip can be found using that metric here as well. Storms like Super Typhoon Lan from 2017 and Super Typhoon Hagibis from 2019 may have been closer to Tip's peak size than many realize.

https://twitter.com/1900hurricane/status/1365863176244453378

https://i.imgur.com/TQGu2n3.png



Also cant help but think about Super Typhoon Mangkhut (2018) when it comes to gargantuan size of a tropical cyclone. If we talk about the extent of TS-force winds from its eye, I think Mangkhut can be considered as one of the largest ever. If I remember correctly, the eye made landfall in the northeastern tip of Luzon in the Philippines, but strong TS winds were experienced as far south as Manila in Southern Luzon, and even in the Visayas region (although one can argue that this is due to the monsoon enhanced by Mangkhut's circulation).
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Re: Discussion of Intense Tropical Cyclones

#624 Postby CrazyC83 » Tue May 18, 2021 3:52 pm

With all the talk about the SFMR running high, I think Matthew 2016 needs revisiting. Here are changes I would make to the intensities in the first half of the lifespan knowing our findings. Changes are bolded - green are weaker, red are stronger (no points have a higher intensity).

AL142016, MATTHEW, 50,
20160928, 1200, , TS, 13.4N, 59.8W, 50, 1009, 180, 180, 0, 90, 90, 0, 0, 0, 0, 0, 0, 0,
20160928, 1800, , TS, 13.6N, 61.2W, 50, 1008, 180, 180, 0, 100, 90, 0, 0, 0, 0, 0, 0, 0,
20160929, 0000, , TS, 13.9N, 62.6W, 55, 1004, 180, 180, 0, 110, 90, 0, 0, 0, 0, 0, 0, 0,
20160929, 0600, , TS, 14.0N, 64.0W, 55, 1002, 180, 160, 0, 120, 90, 0, 0, 80, 0, 0, 0, 0,
20160929, 1200, , TS, 14.1N, 65.5W, 60, 995, 180, 140, 50, 130, 90, 0, 0, 70, 0, 0, 0, 0,
20160929, 1800, , HU, 14.2N, 66.9W, 65, 993, 180, 120, 50, 140, 90, 0, 0, 60, 60, 0, 0, 30,
20160930, 0000, , HU, 14.2N, 68.1W, 70, 987, 170, 120, 50, 150, 90, 0, 0, 60, 50, 0, 0, 30,
20160930, 0600, , HU, 14.0N, 69.3W, 85, 979, 170, 100, 50, 160, 80, 30, 30, 60, 40, 20, 15, 30,
20160930, 1200, , HU, 13.8N, 70.4W, 95, 968, 170, 90, 50, 170, 80, 30, 30, 80, 30, 20, 15, 30,
20160930, 1800, , HU, 13.5N, 71.2W, 115, 955, 170, 90, 60, 170, 80, 30, 30, 80, 30, 20, 15, 30,
20161001, 0000, , HU, 13.4N, 71.9W, 130, 942, 170, 90, 60, 170, 80, 30, 30, 70, 30, 20, 15, 40,
20161001, 0600, , HU, 13.4N, 72.5W, 130, 942, 170, 90, 50, 170, 80, 30, 30, 70, 30, 20, 15, 40,
20161001, 1200, , HU, 13.4N, 73.1W, 125, 944, 170, 90, 60, 170, 70, 40, 30, 70, 25, 20, 15, 25,
20161001, 1800, , HU, 13.4N, 73.3W, 120, 942, 170, 90, 70, 170, 70, 40, 30, 50, 20, 20, 15, 25,
20161002, 0000, , HU, 13.5N, 73.5W, 120, 940, 170, 90, 70, 160, 70, 40, 30, 50, 25, 20, 20, 25,
20161002, 0600, , HU, 13.7N, 73.9W, 120, 941, 170, 70, 70, 160, 60, 40, 30, 50, 25, 20, 20, 25,
20161002, 1200, , HU, 14.0N, 74.3W, 125, 947, 170, 80, 70, 150, 60, 40, 30, 50, 25, 20, 15, 25,
20161002, 1800, , HU, 14.2N, 74.7W, 125, 945, 170, 90, 70, 140, 60, 40, 30, 50, 25, 20, 15, 25,
20161003, 0000, , HU, 14.5N, 75.0W, 120, 944, 170, 100, 80, 130, 60, 50, 30, 50, 30, 20, 20, 25,
20161003, 0600, , HU, 14.9N, 75.0W, 115, 942, 170, 110, 80, 130, 60, 50, 40, 50, 30, 25, 20, 25,
20161003, 1200, , HU, 15.4N, 75.0W, 115, 941, 170, 120, 80, 120, 60, 50, 40, 50, 30, 25, 20, 25,
20161003, 1800, , HU, 15.9N, 74.9W, 125, 938, 170, 130, 90, 120, 70, 50, 50, 50, 35, 30, 30, 30,
20161004, 0000, , HU, 16.6N, 74.6W, 130, 934, 170, 140, 90, 110, 70, 60, 50, 50, 35, 30, 30, 30,
20161004, 0600, , HU, 17.5N, 74.4W, 130, 934, 170, 150, 90, 100, 70, 60, 50, 60, 35, 35, 30, 30,
20161004, 1100, L, HU, 18.3N, 74.3W, 130, 935, 170, 150, 90, 100, 70, 60, 50, 60, 35, 35, 30, 30,
20161004, 1200, , HU, 18.4N, 74.3W, 125, 937, 170, 150, 90, 100, 70, 60, 50, 60, 35, 40, 30, 30,
20161004, 1800, , HU, 19.3N, 74.3W, 115, 947, 160, 150, 90, 100, 70, 60, 50, 60, 40, 40, 40, 40,
20161005, 0000, L, HU, 20.1N, 74.3W, 115, 949, 160, 150, 90, 100, 70, 60, 50, 60, 40, 40, 40, 40,

(No changes after Cuban landfall)

Yes, that would knock it back from being a category 5 to a category 4. However, the SFMR ran well above the flight-level winds for most of that time. In fact, at the time of the current peak, flight level winds were only 134 kt - which would result in a 120 kt intensity at face value. (The highest flight level winds, 142 kt, were just before landfall in Haiti.)

No landfalls change intensities - the peak of 130 kt would be both at the SFMR peak in the southern Caribbean as well as at Haiti landfall. I personally would consider a 135 kt intensity when it hit Haiti, but that would be based on satellite interpretation and hence I didn't adjust it here.
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Re: Discussion of Intense Tropical Cyclones

#625 Postby Shell Mound » Tue May 18, 2021 4:09 pm

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Re: Discussion of Intense Tropical Cyclones

#626 Postby ElectricStorm » Tue May 18, 2021 5:19 pm

CrazyC83 wrote:With all the talk about the SFMR running high, I think Matthew 2016 needs revisiting. Here are changes I would make to the intensities in the first half of the lifespan knowing our findings. Changes are bolded - green are weaker, red are stronger (no points have a higher intensity).

AL142016, MATTHEW, 50,
20160928, 1200, , TS, 13.4N, 59.8W, 50, 1009, 180, 180, 0, 90, 90, 0, 0, 0, 0, 0, 0, 0,
20160928, 1800, , TS, 13.6N, 61.2W, 50, 1008, 180, 180, 0, 100, 90, 0, 0, 0, 0, 0, 0, 0,
20160929, 0000, , TS, 13.9N, 62.6W, 55, 1004, 180, 180, 0, 110, 90, 0, 0, 0, 0, 0, 0, 0,
20160929, 0600, , TS, 14.0N, 64.0W, 55, 1002, 180, 160, 0, 120, 90, 0, 0, 80, 0, 0, 0, 0,
20160929, 1200, , TS, 14.1N, 65.5W, 60, 995, 180, 140, 50, 130, 90, 0, 0, 70, 0, 0, 0, 0,
20160929, 1800, , HU, 14.2N, 66.9W, 65, 993, 180, 120, 50, 140, 90, 0, 0, 60, 60, 0, 0, 30,
20160930, 0000, , HU, 14.2N, 68.1W, 70, 987, 170, 120, 50, 150, 90, 0, 0, 60, 50, 0, 0, 30,
20160930, 0600, , HU, 14.0N, 69.3W, 85, 979, 170, 100, 50, 160, 80, 30, 30, 60, 40, 20, 15, 30,
20160930, 1200, , HU, 13.8N, 70.4W, 95, 968, 170, 90, 50, 170, 80, 30, 30, 80, 30, 20, 15, 30,
20160930, 1800, , HU, 13.5N, 71.2W, 115, 955, 170, 90, 60, 170, 80, 30, 30, 80, 30, 20, 15, 30,
20161001, 0000, , HU, 13.4N, 71.9W, 130, 942, 170, 90, 60, 170, 80, 30, 30, 70, 30, 20, 15, 40,
20161001, 0600, , HU, 13.4N, 72.5W, 130, 942, 170, 90, 50, 170, 80, 30, 30, 70, 30, 20, 15, 40,
20161001, 1200, , HU, 13.4N, 73.1W, 125, 944, 170, 90, 60, 170, 70, 40, 30, 70, 25, 20, 15, 25,
20161001, 1800, , HU, 13.4N, 73.3W, 120, 942, 170, 90, 70, 170, 70, 40, 30, 50, 20, 20, 15, 25,
20161002, 0000, , HU, 13.5N, 73.5W, 120, 940, 170, 90, 70, 160, 70, 40, 30, 50, 25, 20, 20, 25,
20161002, 0600, , HU, 13.7N, 73.9W, 120, 941, 170, 70, 70, 160, 60, 40, 30, 50, 25, 20, 20, 25,
20161002, 1200, , HU, 14.0N, 74.3W, 125, 947, 170, 80, 70, 150, 60, 40, 30, 50, 25, 20, 15, 25,
20161002, 1800, , HU, 14.2N, 74.7W, 125, 945, 170, 90, 70, 140, 60, 40, 30, 50, 25, 20, 15, 25,
20161003, 0000, , HU, 14.5N, 75.0W, 120, 944, 170, 100, 80, 130, 60, 50, 30, 50, 30, 20, 20, 25,
20161003, 0600, , HU, 14.9N, 75.0W, 115, 942, 170, 110, 80, 130, 60, 50, 40, 50, 30, 25, 20, 25,
20161003, 1200, , HU, 15.4N, 75.0W, 115, 941, 170, 120, 80, 120, 60, 50, 40, 50, 30, 25, 20, 25,
20161003, 1800, , HU, 15.9N, 74.9W, 125, 938, 170, 130, 90, 120, 70, 50, 50, 50, 35, 30, 30, 30,
20161004, 0000, , HU, 16.6N, 74.6W, 130, 934, 170, 140, 90, 110, 70, 60, 50, 50, 35, 30, 30, 30,
20161004, 0600, , HU, 17.5N, 74.4W, 130, 934, 170, 150, 90, 100, 70, 60, 50, 60, 35, 35, 30, 30,
20161004, 1100, L, HU, 18.3N, 74.3W, 130, 935, 170, 150, 90, 100, 70, 60, 50, 60, 35, 35, 30, 30,
20161004, 1200, , HU, 18.4N, 74.3W, 125, 937, 170, 150, 90, 100, 70, 60, 50, 60, 35, 40, 30, 30,
20161004, 1800, , HU, 19.3N, 74.3W, 115, 947, 160, 150, 90, 100, 70, 60, 50, 60, 40, 40, 40, 40,
20161005, 0000, L, HU, 20.1N, 74.3W, 115, 949, 160, 150, 90, 100, 70, 60, 50, 60, 40, 40, 40, 40,

(No changes after Cuban landfall)

Yes, that would knock it back from being a category 5 to a category 4. However, the SFMR ran well above the flight-level winds for most of that time. In fact, at the time of the current peak, flight level winds were only 134 kt - which would result in a 120 kt intensity at face value. (The highest flight level winds, 142 kt, were just before landfall in Haiti.)

No landfalls change intensities - the peak of 130 kt would be both at the SFMR peak in the southern Caribbean as well as at Haiti landfall. I personally would consider a 135 kt intensity when it hit Haiti, but that would be based on satellite interpretation and hence I didn't adjust it here.

Not to mention the official 934mb pressure at peak which is unheard of for Cat 5s...
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Re: Discussion of Intense Tropical Cyclones

#627 Postby CrazyC83 » Tue May 18, 2021 5:29 pm

Weather Dude wrote:
CrazyC83 wrote:With all the talk about the SFMR running high, I think Matthew 2016 needs revisiting. Here are changes I would make to the intensities in the first half of the lifespan knowing our findings. Changes are bolded - green are weaker, red are stronger (no points have a higher intensity).

AL142016, MATTHEW, 50,
20160928, 1200, , TS, 13.4N, 59.8W, 50, 1009, 180, 180, 0, 90, 90, 0, 0, 0, 0, 0, 0, 0,
20160928, 1800, , TS, 13.6N, 61.2W, 50, 1008, 180, 180, 0, 100, 90, 0, 0, 0, 0, 0, 0, 0,
20160929, 0000, , TS, 13.9N, 62.6W, 55, 1004, 180, 180, 0, 110, 90, 0, 0, 0, 0, 0, 0, 0,
20160929, 0600, , TS, 14.0N, 64.0W, 55, 1002, 180, 160, 0, 120, 90, 0, 0, 80, 0, 0, 0, 0,
20160929, 1200, , TS, 14.1N, 65.5W, 60, 995, 180, 140, 50, 130, 90, 0, 0, 70, 0, 0, 0, 0,
20160929, 1800, , HU, 14.2N, 66.9W, 65, 993, 180, 120, 50, 140, 90, 0, 0, 60, 60, 0, 0, 30,
20160930, 0000, , HU, 14.2N, 68.1W, 70, 987, 170, 120, 50, 150, 90, 0, 0, 60, 50, 0, 0, 30,
20160930, 0600, , HU, 14.0N, 69.3W, 85, 979, 170, 100, 50, 160, 80, 30, 30, 60, 40, 20, 15, 30,
20160930, 1200, , HU, 13.8N, 70.4W, 95, 968, 170, 90, 50, 170, 80, 30, 30, 80, 30, 20, 15, 30,
20160930, 1800, , HU, 13.5N, 71.2W, 115, 955, 170, 90, 60, 170, 80, 30, 30, 80, 30, 20, 15, 30,
20161001, 0000, , HU, 13.4N, 71.9W, 130, 942, 170, 90, 60, 170, 80, 30, 30, 70, 30, 20, 15, 40,
20161001, 0600, , HU, 13.4N, 72.5W, 130, 942, 170, 90, 50, 170, 80, 30, 30, 70, 30, 20, 15, 40,
20161001, 1200, , HU, 13.4N, 73.1W, 125, 944, 170, 90, 60, 170, 70, 40, 30, 70, 25, 20, 15, 25,
20161001, 1800, , HU, 13.4N, 73.3W, 120, 942, 170, 90, 70, 170, 70, 40, 30, 50, 20, 20, 15, 25,
20161002, 0000, , HU, 13.5N, 73.5W, 120, 940, 170, 90, 70, 160, 70, 40, 30, 50, 25, 20, 20, 25,
20161002, 0600, , HU, 13.7N, 73.9W, 120, 941, 170, 70, 70, 160, 60, 40, 30, 50, 25, 20, 20, 25,
20161002, 1200, , HU, 14.0N, 74.3W, 125, 947, 170, 80, 70, 150, 60, 40, 30, 50, 25, 20, 15, 25,
20161002, 1800, , HU, 14.2N, 74.7W, 125, 945, 170, 90, 70, 140, 60, 40, 30, 50, 25, 20, 15, 25,
20161003, 0000, , HU, 14.5N, 75.0W, 120, 944, 170, 100, 80, 130, 60, 50, 30, 50, 30, 20, 20, 25,
20161003, 0600, , HU, 14.9N, 75.0W, 115, 942, 170, 110, 80, 130, 60, 50, 40, 50, 30, 25, 20, 25,
20161003, 1200, , HU, 15.4N, 75.0W, 115, 941, 170, 120, 80, 120, 60, 50, 40, 50, 30, 25, 20, 25,
20161003, 1800, , HU, 15.9N, 74.9W, 125, 938, 170, 130, 90, 120, 70, 50, 50, 50, 35, 30, 30, 30,
20161004, 0000, , HU, 16.6N, 74.6W, 130, 934, 170, 140, 90, 110, 70, 60, 50, 50, 35, 30, 30, 30,
20161004, 0600, , HU, 17.5N, 74.4W, 130, 934, 170, 150, 90, 100, 70, 60, 50, 60, 35, 35, 30, 30,
20161004, 1100, L, HU, 18.3N, 74.3W, 130, 935, 170, 150, 90, 100, 70, 60, 50, 60, 35, 35, 30, 30,
20161004, 1200, , HU, 18.4N, 74.3W, 125, 937, 170, 150, 90, 100, 70, 60, 50, 60, 35, 40, 30, 30,
20161004, 1800, , HU, 19.3N, 74.3W, 115, 947, 160, 150, 90, 100, 70, 60, 50, 60, 40, 40, 40, 40,
20161005, 0000, L, HU, 20.1N, 74.3W, 115, 949, 160, 150, 90, 100, 70, 60, 50, 60, 40, 40, 40, 40,

(No changes after Cuban landfall)

Yes, that would knock it back from being a category 5 to a category 4. However, the SFMR ran well above the flight-level winds for most of that time. In fact, at the time of the current peak, flight level winds were only 134 kt - which would result in a 120 kt intensity at face value. (The highest flight level winds, 142 kt, were just before landfall in Haiti.)

No landfalls change intensities - the peak of 130 kt would be both at the SFMR peak in the southern Caribbean as well as at Haiti landfall. I personally would consider a 135 kt intensity when it hit Haiti, but that would be based on satellite interpretation and hence I didn't adjust it here.

Not to mention the official 934mb pressure at peak which is unheard of for Cat 5s...


That wasn't even at that time. At the 145 kt peak, Matthew's pressure was 942 mb.
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Re: Discussion of Intense Tropical Cyclones

#628 Postby aspen » Tue May 18, 2021 6:13 pm

CrazyC83 wrote:
Weather Dude wrote:
CrazyC83 wrote:With all the talk about the SFMR running high, I think Matthew 2016 needs revisiting. Here are changes I would make to the intensities in the first half of the lifespan knowing our findings. Changes are bolded - green are weaker, red are stronger (no points have a higher intensity).

AL142016, MATTHEW, 50,
20160928, 1200, , TS, 13.4N, 59.8W, 50, 1009, 180, 180, 0, 90, 90, 0, 0, 0, 0, 0, 0, 0,
20160928, 1800, , TS, 13.6N, 61.2W, 50, 1008, 180, 180, 0, 100, 90, 0, 0, 0, 0, 0, 0, 0,
20160929, 0000, , TS, 13.9N, 62.6W, 55, 1004, 180, 180, 0, 110, 90, 0, 0, 0, 0, 0, 0, 0,
20160929, 0600, , TS, 14.0N, 64.0W, 55, 1002, 180, 160, 0, 120, 90, 0, 0, 80, 0, 0, 0, 0,
20160929, 1200, , TS, 14.1N, 65.5W, 60, 995, 180, 140, 50, 130, 90, 0, 0, 70, 0, 0, 0, 0,
20160929, 1800, , HU, 14.2N, 66.9W, 65, 993, 180, 120, 50, 140, 90, 0, 0, 60, 60, 0, 0, 30,
20160930, 0000, , HU, 14.2N, 68.1W, 70, 987, 170, 120, 50, 150, 90, 0, 0, 60, 50, 0, 0, 30,
20160930, 0600, , HU, 14.0N, 69.3W, 85, 979, 170, 100, 50, 160, 80, 30, 30, 60, 40, 20, 15, 30,
20160930, 1200, , HU, 13.8N, 70.4W, 95, 968, 170, 90, 50, 170, 80, 30, 30, 80, 30, 20, 15, 30,
20160930, 1800, , HU, 13.5N, 71.2W, 115, 955, 170, 90, 60, 170, 80, 30, 30, 80, 30, 20, 15, 30,
20161001, 0000, , HU, 13.4N, 71.9W, 130, 942, 170, 90, 60, 170, 80, 30, 30, 70, 30, 20, 15, 40,
20161001, 0600, , HU, 13.4N, 72.5W, 130, 942, 170, 90, 50, 170, 80, 30, 30, 70, 30, 20, 15, 40,
20161001, 1200, , HU, 13.4N, 73.1W, 125, 944, 170, 90, 60, 170, 70, 40, 30, 70, 25, 20, 15, 25,
20161001, 1800, , HU, 13.4N, 73.3W, 120, 942, 170, 90, 70, 170, 70, 40, 30, 50, 20, 20, 15, 25,
20161002, 0000, , HU, 13.5N, 73.5W, 120, 940, 170, 90, 70, 160, 70, 40, 30, 50, 25, 20, 20, 25,
20161002, 0600, , HU, 13.7N, 73.9W, 120, 941, 170, 70, 70, 160, 60, 40, 30, 50, 25, 20, 20, 25,
20161002, 1200, , HU, 14.0N, 74.3W, 125, 947, 170, 80, 70, 150, 60, 40, 30, 50, 25, 20, 15, 25,
20161002, 1800, , HU, 14.2N, 74.7W, 125, 945, 170, 90, 70, 140, 60, 40, 30, 50, 25, 20, 15, 25,
20161003, 0000, , HU, 14.5N, 75.0W, 120, 944, 170, 100, 80, 130, 60, 50, 30, 50, 30, 20, 20, 25,
20161003, 0600, , HU, 14.9N, 75.0W, 115, 942, 170, 110, 80, 130, 60, 50, 40, 50, 30, 25, 20, 25,
20161003, 1200, , HU, 15.4N, 75.0W, 115, 941, 170, 120, 80, 120, 60, 50, 40, 50, 30, 25, 20, 25,
20161003, 1800, , HU, 15.9N, 74.9W, 125, 938, 170, 130, 90, 120, 70, 50, 50, 50, 35, 30, 30, 30,
20161004, 0000, , HU, 16.6N, 74.6W, 130, 934, 170, 140, 90, 110, 70, 60, 50, 50, 35, 30, 30, 30,
20161004, 0600, , HU, 17.5N, 74.4W, 130, 934, 170, 150, 90, 100, 70, 60, 50, 60, 35, 35, 30, 30,
20161004, 1100, L, HU, 18.3N, 74.3W, 130, 935, 170, 150, 90, 100, 70, 60, 50, 60, 35, 35, 30, 30,
20161004, 1200, , HU, 18.4N, 74.3W, 125, 937, 170, 150, 90, 100, 70, 60, 50, 60, 35, 40, 30, 30,
20161004, 1800, , HU, 19.3N, 74.3W, 115, 947, 160, 150, 90, 100, 70, 60, 50, 60, 40, 40, 40, 40,
20161005, 0000, L, HU, 20.1N, 74.3W, 115, 949, 160, 150, 90, 100, 70, 60, 50, 60, 40, 40, 40, 40,

(No changes after Cuban landfall)

Yes, that would knock it back from being a category 5 to a category 4. However, the SFMR ran well above the flight-level winds for most of that time. In fact, at the time of the current peak, flight level winds were only 134 kt - which would result in a 120 kt intensity at face value. (The highest flight level winds, 142 kt, were just before landfall in Haiti.)

No landfalls change intensities - the peak of 130 kt would be both at the SFMR peak in the southern Caribbean as well as at Haiti landfall. I personally would consider a 135 kt intensity when it hit Haiti, but that would be based on satellite interpretation and hence I didn't adjust it here.

Not to mention the official 934mb pressure at peak which is unheard of for Cat 5s...


That wasn't even at that time. At the 145 kt peak, Matthew's pressure was 942 mb.

No way in hell Matthew was a Cat 5 if Iota was a Cat 4 despite a 140 kt valid SFMR measurement and Dvorak support for 140 kt.

Once again, I have to wonder about Dorian’s SFMR. Unlike Iota, Dorian had extremely high FL winds in all four quadrants (~160 kt in at least one quadrant), and dropsondes recorded that rare V signature showing that air was sinking all the way down to the surface, indicating winds would be translating from FL to the surface rather well. All quadrants also had 160 kt or greater valid SFMR measurements, and some even got up to 170 kt. Maybe the low ocean depth was messing with SFMR, but with effective translation of ~160 kt FL winds to the surface, it’s hard to believe they’re that erroneous.
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Re: Discussion of Intense Tropical Cyclones

#629 Postby ncforecaster89 » Tue May 18, 2021 8:17 pm

aspen wrote:
CrazyC83 wrote:
Weather Dude wrote:Not to mention the official 934mb pressure at peak which is unheard of for Cat 5s...


That wasn't even at that time. At the 145 kt peak, Matthew's pressure was 942 mb.

No way in hell Matthew was a Cat 5 if Iota was a Cat 4 despite a 140 kt valid SFMR measurement and Dvorak support for 140 kt.

Once again, I have to wonder about Dorian’s SFMR. Unlike Iota, Dorian had extremely high FL winds in all four quadrants (~160 kt in at least one quadrant), and dropsondes recorded that rare V signature showing that air was sinking all the way down to the surface, indicating winds would be translating from FL to the surface rather well. All quadrants also had 160 kt or greater valid SFMR measurements, and some even got up to 170 kt. Maybe the low ocean depth was messing with SFMR, but with effective translation of ~160 kt FL winds to the surface, it’s hard to believe they’re that erroneous.


I agree, as others have already stated, that Matthew should be downgraded based on the apparent high bias of the SFMR data in surface winds > 120 kt. Might be an unpopular opinion, but I’ve always felt Dorian was overestimated with the 160 kt estimate; which is way too high a figure considering the 700 mb FLWs of 161 kt (corresponds to only 145 kt). The SFMR is the only data that supported such an extreme estimate and I feel 150 kt is likely a more accurate representation of its MSW at its peak.

Although Dorian currently sits above Irma, the exclusion of the SFMR data would likely put them at the same intensity of 150 kt. Personally, I find Irma to be the more impressive hurricane of the two and actually had a higher 700 mb FLW of 164 kt. Even though I still think of Dorian as an incredibly powerful Cat 5, it should not be tied with the GLDH of 1935...based on the available data.
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Re: Discussion of Intense Tropical Cyclones

#630 Postby CrazyC83 » Tue May 18, 2021 11:36 pm

ncforecaster89 wrote:
aspen wrote:
CrazyC83 wrote:
That wasn't even at that time. At the 145 kt peak, Matthew's pressure was 942 mb.

No way in hell Matthew was a Cat 5 if Iota was a Cat 4 despite a 140 kt valid SFMR measurement and Dvorak support for 140 kt.

Once again, I have to wonder about Dorian’s SFMR. Unlike Iota, Dorian had extremely high FL winds in all four quadrants (~160 kt in at least one quadrant), and dropsondes recorded that rare V signature showing that air was sinking all the way down to the surface, indicating winds would be translating from FL to the surface rather well. All quadrants also had 160 kt or greater valid SFMR measurements, and some even got up to 170 kt. Maybe the low ocean depth was messing with SFMR, but with effective translation of ~160 kt FL winds to the surface, it’s hard to believe they’re that erroneous.


I agree, as others have already stated, that Matthew should be downgraded based on the apparent high bias of the SFMR data in surface winds > 120 kt. Might be an unpopular opinion, but I’ve always felt Dorian was overestimated with the 160 kt estimate; which is way too high a figure considering the 700 mb FLWs of 161 kt (corresponds to only 145 kt). The SFMR is the only data that supported such an extreme estimate and I feel 150 kt is likely a more accurate representation of its MSW at its peak.

Although Dorian currently sits above Irma, the exclusion of the SFMR data would likely put them at the same intensity of 150 kt. Personally, I find Irma to be the more impressive hurricane of the two and actually had a higher 700 mb FLW of 164 kt. Even though I still think of Dorian as an incredibly powerful Cat 5, it should not be tied with the GLDH of 1935...based on the available data.


Irma also had a surface observation of note: an official gust of (I believe) 173 kt in St. Martin. That lends itself well to an intensity of 155 kt, which I believe is reasonable. Dorian is a case with an even greater discrepancy. 150 or 155 kt would likely make more sense, but at that time 160 kt seemed best with the investigation underway. Dorian's floor is probably 150 kt.

For all the recent strong 4s and 5s (i.e. 130 kt or greater):

Matthew - FLW 134/121 at surface, SFMR 143, Dvorak 127, P-W 118. BT is 145 kt but my estimate is 130 kt at that time.
Irma - FLW 164/148 (and 170 at non-standard/about 150), SFMR 160, Dvorak 140, P-W 152, surface G173. BT is 155 kt and reasonable.
Jose - FLW 144/130, SFMR 142, Dvorak 115, P-W 125, no surface data. BT is 135 kt and probably reasonable (the thoughts of it being cat 5 are likely gone now).
Maria - FLW 157/141, SFMR 152, Dvorak 140, P-W 154. BT is 150 kt and probably reasonable.
Michael - FLW 152/137, SFMR 138 (and suspect), Dvorak 140, P-W 141, radar 147. BT is 140 kt, although a case for 145 kt could be made.
Dorian - FLW 161/145, SFMR 178, Dvorak 127, P-W 154. BT is 160 kt with a high degree of uncertainty; floor is 150 kt with 155 kt also reasonable.
Lorenzo - Dvorak 140 but no other data. BT is 140 kt and hard to argue.
Laura - FLW 148/133, SFMR 138 (and suspect), Dvorak 127, P-W 124, radar ~135. Operational BT is 130 kt, awaiting TCR. My best estimate is 135 kt.
Eta - FLW 137/123 (very limited data), SFMR 135, Dvorak 140, P-W 137. Operational BT is 130 kt, awaiting TCR.
Iota - FLW 143/129, SFMR 140, Dvorak 140, P-W 145. BT is 135 kt, which is the current source of controversy but the flight-level winds don't support higher.
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Re: Discussion of Intense Tropical Cyclones

#631 Postby EquusStorm » Wed May 19, 2021 2:06 am

Our arbitrary classification thresholds make a small deviation in winds once reanalyzed a lot bigger seeming of a deal than it probably is. 135 to 130kt or 145 to 140 would have barely been noticed, but 140 to 135 seems like a tremendous deal as it undoes a lot of records relating to our classification thresholds. Strongly dislike the downgrade for said record reasons (my birthday category five is denied) but if that's what the science says it's what must be done I guess; desperately need conclusive SFMR research findings to settle it once and for all

As soon as they downgrade Matthew, it'll seem much less of an anomaly (and no longer be the only modern category five downgraded after the fact)
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Re: Discussion of Intense Tropical Cyclones

#632 Postby Shell Mound » Wed May 19, 2021 6:23 am

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Re: Discussion of Intense Tropical Cyclones

#633 Postby aspen » Wed May 19, 2021 6:52 am

CrazyC83 wrote:
ncforecaster89 wrote:
aspen wrote:No way in hell Matthew was a Cat 5 if Iota was a Cat 4 despite a 140 kt valid SFMR measurement and Dvorak support for 140 kt.

Once again, I have to wonder about Dorian’s SFMR. Unlike Iota, Dorian had extremely high FL winds in all four quadrants (~160 kt in at least one quadrant), and dropsondes recorded that rare V signature showing that air was sinking all the way down to the surface, indicating winds would be translating from FL to the surface rather well. All quadrants also had 160 kt or greater valid SFMR measurements, and some even got up to 170 kt. Maybe the low ocean depth was messing with SFMR, but with effective translation of ~160 kt FL winds to the surface, it’s hard to believe they’re that erroneous.


I agree, as others have already stated, that Matthew should be downgraded based on the apparent high bias of the SFMR data in surface winds > 120 kt. Might be an unpopular opinion, but I’ve always felt Dorian was overestimated with the 160 kt estimate; which is way too high a figure considering the 700 mb FLWs of 161 kt (corresponds to only 145 kt). The SFMR is the only data that supported such an extreme estimate and I feel 150 kt is likely a more accurate representation of its MSW at its peak.

Although Dorian currently sits above Irma, the exclusion of the SFMR data would likely put them at the same intensity of 150 kt. Personally, I find Irma to be the more impressive hurricane of the two and actually had a higher 700 mb FLW of 164 kt. Even though I still think of Dorian as an incredibly powerful Cat 5, it should not be tied with the GLDH of 1935...based on the available data.


Irma also had a surface observation of note: an official gust of (I believe) 173 kt in St. Martin. That lends itself well to an intensity of 155 kt, which I believe is reasonable. Dorian is a case with an even greater discrepancy. 150 or 155 kt would likely make more sense, but at that time 160 kt seemed best with the investigation underway. Dorian's floor is probably 150 kt.

For all the recent strong 4s and 5s (i.e. 130 kt or greater):

Matthew - FLW 134/121 at surface, SFMR 143, Dvorak 127, P-W 118. BT is 145 kt but my estimate is 130 kt at that time.
Irma - FLW 164/148 (and 170 at non-standard/about 150), SFMR 160, Dvorak 140, P-W 152, surface G173. BT is 155 kt and reasonable.
Jose - FLW 144/130, SFMR 142, Dvorak 115, P-W 125, no surface data. BT is 135 kt and probably reasonable (the thoughts of it being cat 5 are likely gone now).
Maria - FLW 157/141, SFMR 152, Dvorak 140, P-W 154. BT is 150 kt and probably reasonable.
Michael - FLW 152/137, SFMR 138 (and suspect), Dvorak 140, P-W 141, radar 147. BT is 140 kt, although a case for 145 kt could be made.
Dorian - FLW 161/145, SFMR 178, Dvorak 127, P-W 154. BT is 160 kt with a high degree of uncertainty; floor is 150 kt with 155 kt also reasonable.
Lorenzo - Dvorak 140 but no other data. BT is 140 kt and hard to argue.
Laura - FLW 148/133, SFMR 138 (and suspect), Dvorak 127, P-W 124, radar ~135. Operational BT is 130 kt, awaiting TCR. My best estimate is 135 kt.
Eta - FLW 137/123 (very limited data), SFMR 135, Dvorak 140, P-W 137. Operational BT is 130 kt, awaiting TCR.
Iota - FLW 143/129, SFMR 140, Dvorak 140, P-W 145. BT is 135 kt, which is the current source of controversy but the flight-level winds don't support higher.

I’m starting to think it’s entirely possible Eta could get downgraded to 125 kt. FL winds in both passes were around 130-135 kt, so a standard conversion factor would get mid Cat 4 surface winds. The validity of the 130-140 kt SFMR readings will also need to be checked since a lot of readings throughout the entire flight — even well outside the eye — were flagged. I don’t think ADT got above 125 kt despite the record-high raw T-numbers.

However, the final eyewall dropsonde of the night recorded surface winds of 150-155 kt, although those might’ve just been gusts. Still, it’s something to take into consideration. Another think to take into consideration is how Eta’s pressure was still falling like a rock (it had a deepening rate of ~5 mb/hr between passes), so it’s clear it was still intensifying during the limited time recon was there.
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Re: Discussion of Intense Tropical Cyclones

#634 Postby doomhaMwx » Sun Jun 27, 2021 2:52 am

Came across some papers about buoy observations during Cyclone Phailin (2013) in the Bay of Bengal. One buoy recorded an exceptionally low SLP of 920.6 mb very near the eye on Oct 11 08Z, which happens to be the lowest ever measured by any in-situ instrument in the NIO. IMD kept Phailin's peak at 115kt 940mb in their best track — I wonder if they were not aware of this valuable data?

Image
Image

 https://twitter.com/doomhaMwx/status/1409053894651506689




The buoy didn't capture Phailin's peak since the TC was undergoing an EWRC at that time but resumed intensifying afterward. At its 1st and/or 2nd peak, it may have actually rivaled/surpassed the NIO's official 912mb record set by the "1999 Odisha Cyclone".

Image
Image

Links to papers:
1) https://www.researchgate.net/publicatio ... _of_Bengal
2) https://journals.ametsoc.org/downloadpd ... 0051.1.pdf
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Re: Discussion of Intense Tropical Cyclones

#635 Postby TROPICALCYCLONEALERT » Fri Jul 09, 2021 3:13 pm

ncforecaster89 wrote:
aspen wrote:
CrazyC83 wrote:
That wasn't even at that time. At the 145 kt peak, Matthew's pressure was 942 mb.

No way in hell Matthew was a Cat 5 if Iota was a Cat 4 despite a 140 kt valid SFMR measurement and Dvorak support for 140 kt.

Once again, I have to wonder about Dorian’s SFMR. Unlike Iota, Dorian had extremely high FL winds in all four quadrants (~160 kt in at least one quadrant), and dropsondes recorded that rare V signature showing that air was sinking all the way down to the surface, indicating winds would be translating from FL to the surface rather well. All quadrants also had 160 kt or greater valid SFMR measurements, and some even got up to 170 kt. Maybe the low ocean depth was messing with SFMR, but with effective translation of ~160 kt FL winds to the surface, it’s hard to believe they’re that erroneous.


I agree, as others have already stated, that Matthew should be downgraded based on the apparent high bias of the SFMR data in surface winds > 120 kt. Might be an unpopular opinion, but I’ve always felt Dorian was overestimated with the 160 kt estimate; which is way too high a figure considering the 700 mb FLWs of 161 kt (corresponds to only 145 kt). The SFMR is the only data that supported such an extreme estimate and I feel 150 kt is likely a more accurate representation of its MSW at its peak.

Although Dorian currently sits above Irma, the exclusion of the SFMR data would likely put them at the same intensity of 150 kt. Personally, I find Irma to be the more impressive hurricane of the two and actually had a higher 700 mb FLW of 164 kt. Even though I still think of Dorian as an incredibly powerful Cat 5, it should not be tied with the GLDH of 1935...based on the available data.


For what it’s worth, a casual analysis of dropwindsondes in Hurricane Dorian (made possibly only because of the plethora of RMW drops we had from two planes flying into it at peak intensity) implies a flight level wind reduction above the 90% “rule” established by Franklin et al. 2003, albeit still within their accepted range. Anecdotally, storms with higher winds also have a tendency to possess surface winds that are abnormally high relative to the winds found at 700mb, though possible reasons are still unclear and could range from the vertical orientation of the eyewall, the depth of convection, nearness to MPI, and size of the eye. It’s also probable that an extremely healthy system would exceed the statistical average of ~90%, as it would not have to contend with dry air/wind shear interrupting the process that mixes the winds down to the surface. While I’m fairly skeptical of the maximum 177 knot SFMRs in Dorian, I do believe the NHC’s estimate is fairly decent, especially when given the typical 5-10 kt error bound.
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Re: Discussion of Intense Tropical Cyclones

#636 Postby InfernoFlameCat » Tue Jul 13, 2021 12:53 pm

I have to bring up Labor day 1935 hurricane again. I believe this system was probably in excess of 200 mph. It bent railroad tracks, sandblasted people to death(some of the descriptions were dematerialized, thats on another scale,) , and had an unverified barometric pressure of 880 recorded by Ed butters. https://www.facebook.com/permalink.php? ... 3543822331
https://www.baynews9.com/fl/tampa/weath ... %20Florida.
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Re: Discussion of Intense Tropical Cyclones

#637 Postby Category5Kaiju » Mon Jul 19, 2021 2:24 pm

InfernoFlameCat wrote:I have to bring up Labor day 1935 hurricane again. I believe this system was probably in excess of 200 mph. It bent railroad tracks, sandblasted people to death(some of the descriptions were dematerialized, thats on another scale,) , and had an unverified barometric pressure of 880 recorded by Ed butters. https://www.facebook.com/permalink.php? ... 3543822331
https://www.baynews9.com/fl/tampa/weath ... %20Florida.


Not sure if the technology is around currently, but I think a reconstructed colorized picture of what the 1935 Labor Day hurricane could have looked like if it were to be viewed from satellite at its max strength (just like the way we currently view pictures of storms) would be very cool to see.
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Re: Discussion of Intense Tropical Cyclones

#638 Postby ncforecaster89 » Wed Aug 11, 2021 2:08 am

TROPICALCYCLONEALERT wrote:
ncforecaster89 wrote:
aspen wrote:No way in hell Matthew was a Cat 5 if Iota was a Cat 4 despite a 140 kt valid SFMR measurement and Dvorak support for 140 kt.

Once again, I have to wonder about Dorian’s SFMR. Unlike Iota, Dorian had extremely high FL winds in all four quadrants (~160 kt in at least one quadrant), and dropsondes recorded that rare V signature showing that air was sinking all the way down to the surface, indicating winds would be translating from FL to the surface rather well. All quadrants also had 160 kt or greater valid SFMR measurements, and some even got up to 170 kt. Maybe the low ocean depth was messing with SFMR, but with effective translation of ~160 kt FL winds to the surface, it’s hard to believe they’re that erroneous.


I agree, as others have already stated, that Matthew should be downgraded based on the apparent high bias of the SFMR data in surface winds > 120 kt. Might be an unpopular opinion, but I’ve always felt Dorian was overestimated with the 160 kt estimate; which is way too high a figure considering the 700 mb FLWs of 161 kt (corresponds to only 145 kt). The SFMR is the only data that supported such an extreme estimate and I feel 150 kt is likely a more accurate representation of its MSW at its peak.

Although Dorian currently sits above Irma, the exclusion of the SFMR data would likely put them at the same intensity of 150 kt. Personally, I find Irma to be the more impressive hurricane of the two and actually had a higher 700 mb FLW of 164 kt. Even though I still think of Dorian as an incredibly powerful Cat 5, it should not be tied with the GLDH of 1935...based on the available data.


For what it’s worth, a casual analysis of dropwindsondes in Hurricane Dorian (made possibly only because of the plethora of RMW drops we had from two planes flying into it at peak intensity) implies a flight level wind reduction above the 90% “rule” established by Franklin et al. 2003, albeit still within their accepted range. Anecdotally, storms with higher winds also have a tendency to possess surface winds that are abnormally high relative to the winds found at 700mb, though possible reasons are still unclear and could range from the vertical orientation of the eyewall, the depth of convection, nearness to MPI, and size of the eye. It’s also probable that an extremely healthy system would exceed the statistical average of ~90%, as it would not have to contend with dry air/wind shear interrupting the process that mixes the winds down to the surface. While I’m fairly skeptical of the maximum 177 knot SFMRs in Dorian, I do believe the NHC’s estimate is fairly decent, especially when given the typical 5-10 kt error bound.


Hi TCA,

So sorry I’m just now reading this post and providing a response.

I don’t disagree with your own synopsis, but want to clarify why I feel rather strongly that the current 160 kt estimate is much too high, and Dorian shouldn’t be tied with the GLDH of 1935. To do so, please allow me to post the NHC’s reasoning for their estimate from the TCR:

“Dorian’s estimated peak intensity of 160 kt at 1640 UTC 1 September, which is also the landfall intensity at Elbow Cay in the Abacos, is based on a blend of flight-level winds, dropwindsonde WL150 winds (average wind speed over the lowest 150 m), and multiple SFMR surface wind speed measurements made by both the Air Force Reserve and NOAA Hurricane Hunters during that time period. This estimate integrates the highest SFMR wind value of 178 kt, a 700-mb flight-level peak wind measurement of 161 kt (which is equivalent to an intensity of 145 kt), and a 1325 UTC WL150 wind speed of 177 kt (which is equivalent to a 10-m wind speed of 147 kt) (Fig. 2). It is important to note that the relationship between the SFMR wind values and the flight-level winds was quite consistent for wind speeds of 120 kt or less in Dorian, but not so for equivalent surface wind speeds exceeding 120 kt. As has been noted for other recent intense hurricanes, the discrepancy between surface winds estimated from historical relationships with the peak flight-level winds and SFMR-derived surface winds leads to greater-than-normal uncertainty in Dorian’s peak intensity estimate. The estimated peak intensity may be revised if SFMR data at high winds are recalibrated.”

As I noted previously, the aforementioned likely inflated SFMR measurements are the only data supportive of an intensity greater than 150 kt. That’s the figure that would be ascertained by blending the peak 700 mb FLW, WL150 winds, satellite intensity estimates, and the wind/pressure relationship. Due to the inherent uncertainty and relative subjective nature involved in determining such intensity estimates, I’m more inclined to err on the high-end side if there’s sufficient in-situ data to support it. In this particular case, I feel 150 kt seems like the most logical and applicable figure for Dorian’s peak MSW.

All that said, I suspect the NHC will ultimately modify the peak intensity down to 155 kt once the SFMR has been recalibrated to account for the apparent inflated values at such extreme wind speeds.
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Re: Discussion of Intense Tropical Cyclones

#639 Postby Shell Mound » Fri Aug 13, 2021 3:55 am

Image
Image

Based on this comparison, Vera of 1979 (top) looks to be even more intense than Haiyan of 2013 (bottom). Vera’s CDO is smaller yet colder, its outflow is more symmetric, and its eye is smaller and likely similarly warm, given satellite-based limitations. If Haiyan was on the order of 170–175 kt, Vera was likely on the order of 175–180 kt. If I recall correctly, quite a few sub-major and low-end major cyclones from the South Pacific and Indian basins were, based on satellite, likely solid and even “high-end” Category-5 cyclones. Dr. Maue once posted an excellent thread on Twitter in regard to “missed” Category 5s, but unfortunately it has been removed.

supercane4867 wrote:
1900hurricane wrote:Another thing worth pointing out is the storm selection that was used was somewhat limited. Some lesser-known C5 TCs from other basins or even "missed" C5 TCs were excluded from the study. I feel like the SPac in particular was underrepresented. Using only C5 TCs, and not even the entire selection of the available ones confined the scope of the study somewhat.


I'm quite perplexed about how they left Hina 85 out of their study. There were also plenty of other noteworthy TCs in the SPAC that could have been included in the study.

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Does anyone have access to data from the Indian and South Pacific basins that comprehensively reanalyse all tropical cyclones on the basis of satellite estimates?

supercane4867, where did you obtain those images of intense tropical cyclones in the South Pacific basin? Was a study done to reanalyse those systems?
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mrbagyo
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Re: Discussion of Intense Tropical Cyclones

#640 Postby mrbagyo » Fri Aug 13, 2021 6:13 am

Shell Mound wrote:Image
Image

Based on this comparison, Vera of 1979 (top) looks to be even more intense than Haiyan of 2013 (bottom). Vera’s CDO is smaller yet colder, its outflow is more symmetric, and its eye is smaller and likely similarly warm, given satellite-based limitations. If Haiyan was on the order of 170–175 kt, Vera was likely on the order of 175–180 kt. If I recall correctly, quite a few sub-major and low-end major cyclones from the South Pacific and Indian basins were, based on satellite, likely solid and even “high-end” Category-5 cyclones. Dr. Maue once posted an excellent thread on Twitter in regard to “missed” Category 5s, but unfortunately it has been removed.



Highest flight level wind recorded by recon in Typhoon Vera was 170 knots.
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