Discussion of Intense Tropical Cyclones

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Re: Discussion of Intense Tropical Cyclones

#161 Postby 1900hurricane » Fri Sep 15, 2017 9:13 pm

supercane4867 wrote:Very interesting tweet from Ryan Maue saying that Cyclone Hina of SPAC, which JTWC previously deemed as a CAT4, was reanalyzed to be 170kts by NHC forecaster Chris Landsea.
I really believe Cyclone Monica and a few other SPAC storms could have reached similar intensities as well. I hope more research for these intense TCs will be done in the near future.



https://twitter.com/RyanMaue/status/908740517416009729


Image

That tweet is actually on the topic of a new Hoarau paper reanalyzing SPac tropical cyclones from the 1980s. I'll probably gain access to it within a few days. I'm interested to see Hoarau's conclusions.



https://twitter.com/RyanMaue/status/908735983516110853
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Re: Discussion of Intense Tropical Cyclones

#162 Postby supercane4867 » Fri Sep 15, 2017 9:26 pm

1900hurricane wrote:
supercane4867 wrote:Very interesting tweet from Ryan Maue saying that Cyclone Hina of SPAC, which JTWC previously deemed as a CAT4, was reanalyzed to be 170kts by NHC forecaster Chris Landsea.
I really believe Cyclone Monica and a few other SPAC storms could have reached similar intensities as well. I hope more research for these intense TCs will be done in the near future.

https://twitter.com/RyanMaue/status/908740517416009729

https://i.imgur.com/gk4hmBr.jpg

That tweet is actually on the topic of a new Hoarau paper reanalyzing SPac tropical cyclones from the 1980s. I'll probably gain access to it within a few days. I'm interested to see Hoarau's conclusions.

https://twitter.com/RyanMaue/status/908735983516110853


Another candidate for top SPAC cyclone from the 1980s that I found is Cyclone Nisha, which identified only as a "CAT3" at the time but had satellite presentation maybe even more impressive than Hina.

Image
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Re: Discussion of Intense Tropical Cyclones

#163 Postby supercane4867 » Fri Sep 15, 2017 9:39 pm

Also, the AVHRR imagery set of Hurricane Gilbert is just plain amazing.
No wonder he became the only Atlantic hurricane received a T8.0 (represented by squares that are off the chart in TC report) .

Image

Image

Image

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Re: Discussion of Intense Tropical Cyclones

#164 Postby Hammy » Fri Sep 15, 2017 11:01 pm

:uarrow: Where do you access the imagery?
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Re: Discussion of Intense Tropical Cyclones

#165 Postby Ntxw » Fri Sep 15, 2017 11:02 pm

supercane4867 wrote:Also, the AVHRR imagery set of Hurricane Gilbert is just plain amazing.
No wonder he became the only Atlantic hurricane received a T8.0 (represented by squares that are off the chart in TC report) .

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

https://i.imgur.com/iG1ixOM.jpg

https://i.imgur.com/fy2Q1cw.jpg

https://i.imgur.com/9lhCU9C.gif


Thank you for posting this! I've been looking for Gilbert satellite information for a long while now. If this is true then Gilbert is the only case of a thick, closed off CDG ring along with Patricia for the WHEM. The only one for the Atlantic basin.

Those SPAC systems certainly look way stronger than their previously designated strengths. 170kts is no walk in the park.
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Re: Discussion of Intense Tropical Cyclones

#166 Postby Ptarmigan » Fri Sep 15, 2017 11:10 pm

I always suspected South Pacific tropical cyclones are underestimated since they are not measured directly.

170 knots is 195 mph! :eek:

Hurricane Gilbert is a very large hurricane for sure. :eek:
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Re: Discussion of Intense Tropical Cyclones

#167 Postby euro6208 » Sat Sep 16, 2017 7:47 am

The South Pacific has probrably the highest OHC and Depth 26C Isotherm, even higher than the West Pacific, in the world. Unlike the WPAC, most of that energy is near the equator where TC's in this part of the world can't get going. It's literally thousands of islands span across a vast ocean. It's like a forgotten world.

Image

http://onlinelibrary.wiley.com/doi/10.1002/joc.5254/abstract
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Re: Discussion of Intense Tropical Cyclones

#168 Postby CrazyC83 » Sat Sep 30, 2017 2:53 pm

euro6208 wrote:The South Pacific has probrably the highest OHC and Depth 26C Isotherm, even higher than the West Pacific, in the world. Unlike the WPAC, most of that energy is near the equator where TC's in this part of the world can't get going. It's literally thousands of islands span across a vast ocean. It's like a forgotten world.

Image

http://onlinelibrary.wiley.com/doi/10.1002/joc.5254/abstract


My intensity guess of those:

Mark - 130 kt (could be higher but the shear on west side suggests maybe T6.5)
Orama - 175 kt (classic T8.0, but a bit less than Haiyan or Patricia)
Oscar - 150 kt (I'd say on the high side of T7.0, the extreme CDG is offset by the less than symmetrical appearance so decreases it a bit)
Reva - 135 kt (almost, but not quite, T7.0)
Tomasi - 120 kt (a difficult one as the CDG area is offset by a sharp gradient so it was sheared; I'd go with T6.0)
Veena - 160 kt (very symmetrical, clearly T7.5 and possibly on the high side)
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Re: Discussion of Intense Tropical Cyclones

#169 Postby CrazyC83 » Sat Sep 30, 2017 2:54 pm

supercane4867 wrote:
1900hurricane wrote:
supercane4867 wrote:Very interesting tweet from Ryan Maue saying that Cyclone Hina of SPAC, which JTWC previously deemed as a CAT4, was reanalyzed to be 170kts by NHC forecaster Chris Landsea.
I really believe Cyclone Monica and a few other SPAC storms could have reached similar intensities as well. I hope more research for these intense TCs will be done in the near future.

https://twitter.com/RyanMaue/status/908740517416009729

https://i.imgur.com/gk4hmBr.jpg

That tweet is actually on the topic of a new Hoarau paper reanalyzing SPac tropical cyclones from the 1980s. I'll probably gain access to it within a few days. I'm interested to see Hoarau's conclusions.

https://twitter.com/RyanMaue/status/908735983516110853


Another candidate for top SPAC cyclone from the 1980s that I found is Cyclone Nisha, which identified only as a "CAT3" at the time but had satellite presentation maybe even more impressive than Hina.

Image
Image


I'd argue for 180 kt on that one. That looks almost as good as Patricia did.

We've learned a lot more since 2010 on the extreme storms. The sample size is small, but data from Megi, Haiyan, Patricia, Meranti and now Irma and Maria (to a lesser extent) help us a lot in determining how strong the greatest of the great storms really are. The flights into Megi and Patricia were especially important.
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Re: Discussion of Intense Tropical Cyclones

#170 Postby supercane4867 » Sat Sep 30, 2017 5:28 pm

CrazyC83 wrote:
euro6208 wrote:The South Pacific has probrably the highest OHC and Depth 26C Isotherm, even higher than the West Pacific, in the world. Unlike the WPAC, most of that energy is near the equator where TC's in this part of the world can't get going. It's literally thousands of islands span across a vast ocean. It's like a forgotten world.

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

http://onlinelibrary.wiley.com/doi/10.1002/joc.5254/abstract


My intensity guess of those:

Mark - 130 kt (could be higher but the shear on west side suggests maybe T6.5)
Orama - 175 kt (classic T8.0, but a bit less than Haiyan or Patricia)
Oscar - 150 kt (I'd say on the high side of T7.0, the extreme CDG is offset by the less than symmetrical appearance so decreases it a bit)
Reva - 135 kt (almost, but not quite, T7.0)
Tomasi - 120 kt (a difficult one as the CDG area is offset by a sharp gradient so it was sheared; I'd go with T6.0)
Veena - 160 kt (very symmetrical, clearly T7.5 and possibly on the high side)


My personal list for top 10 strongest SPAC cyclones in terms of windspeed:

1) Olaf - 180kt (Resembles Patricia in many aspects, Ground data in American Samoa indicates it may had the lowest pressure in SPAC at peak intensity)
2) Monica - 175kt (Perfectly symmetrical CDO with incredible inner core structure. As we have seen in Irma, presentation of microwave imagery can play an important role in determining TC windspeed, in some cases maybe more representative than IR imagery)
3) Hina - 170kt (As shown in re-analysis, very cold CDO with impressive outflow)
4) Zoe - 165kt (Had one of the most impressive outflow pattern in all TCs, plus a very warm eye)
5) Nisha/Orama - 160kt (At least T7.5 based on NOAA7 imagery, but I won't go too far due to lack of satellite data in the 80s)
6) Winston - 155kt (Classic T7.5, operationally listed as 160kt per JTWC)
7) Pam - 150kt (Also T7.5 worthy, but the eye could have been better)
8) Percy Susan Ron - 145kt (tied for 8-10th place)

Note that Nisha and Orama are two names of the same cyclone. The name Nisha was given by FMS while the Tahiti Meteorological Service had named it Orama. Since FMS is the RSMC now, I assume the name Nisha is commonly used.

Here is a comparison of Irma and Monica on microwave imagery

Image
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Re: Discussion of Intense Tropical Cyclones

#171 Postby mrbagyo » Sun Oct 01, 2017 2:34 am

1900hurricane wrote:Ivan and Joan were both very intense and probably fully deserving of their 160 kt intensities. However, I would rank then below the nine storms above. I do believe Ivan and Joan '97 are the only storms to ever coexist at such high intensities. The BD IR images of them below are both from 09Z on October 17th. Ivan is on the left, and Joan is on the right.

Image Image

The images actually overlap the same area a little, so they could actually probably be stitched together.


Sty Gordon 1989 was probably on the same league of Ivan & Joan, Meranti & Megi.

JTWC pegged the peak intensity at 140 knots 898mb based on standard PWR (T7.0) meanwhile JMA had it at 100 knots (10min) 915mb.

What's amazing about Gordon was that it maintained a full CMG ring for almost 24 consecutive hours before its Cat 5 landfall in the mountainous N. Luzon.

I think Gordon was at least 155 knots (T7.5) at peak
:darrow: BD enhanced ir loop of Gordon from 7/14/1989 12:00UTC to 7/16/1989 00:00 UTC
Image
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Re: Discussion of Intense Tropical Cyclones

#172 Postby euro6208 » Sun Oct 01, 2017 5:45 am

mrbagyo wrote:
1900hurricane wrote:Ivan and Joan were both very intense and probably fully deserving of their 160 kt intensities. However, I would rank then below the nine storms above. I do believe Ivan and Joan '97 are the only storms to ever coexist at such high intensities. The BD IR images of them below are both from 09Z on October 17th. Ivan is on the left, and Joan is on the right.

Image Image

The images actually overlap the same area a little, so they could actually probably be stitched together.


Sty Gordon 1989 was probably on the same league of Ivan & Joan, Meranti & Megi.

JTWC pegged the peak intensity at 140 knots 898mb based on standard PWR (T7.0) meanwhile JMA had it at 100 knots (10min) 915mb.

What's amazing about Gordon was that it maintained a full CMG ring for almost 24 consecutive hours before its Cat 5 landfall in the mountainous N. Luzon.

I think Gordon was at least 155 knots (T7.5) at peak
:darrow: BD enhanced ir loop of Gordon from 7/14/1989 12:00UTC to 7/16/1989 00:00 UTC
Image


Looks alot like Super Typhoon Nida from 2009. Interesting how Haiyan (2013) and Megi (2010) started all of this +170 knots talk. Before that no one expected we could reach that benchmark. I wonder what if recon never stopped in 1987. It's really fascinating what they could have found.
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Re: Discussion of Intense Tropical Cyclones

#173 Postby supercane4867 » Sun Oct 01, 2017 5:07 pm

I think the most important takeaway from recon observation of CAT5s in recent years is that the flight level to surface wind relationship is more complex than we thought. Operational practices of NHC in the past typically use the standard 90% reduction factor to estimate surface windspeed from 700mb flight level winds. The introduction of SFMR measurements has lead to new insights on surface windspeed of intense TCs, but it wasn't available on USAF planes until 2007 and didn't become the main basis for assigning peak intensity until mid 2010s. Lack of SMFR presence at peak intensities is very common back to the hyperactive seasons of 2003-05. Nearly all recon flights into recent CAT5s including Felix, Megi, Patricia, Matthew, Irma, and Maria have found the surface winds measured by SFMR and dropsonde were equal or greater than those measured at flight levels. Data indicates the dynamics of these top CAT5 storms may generate surface winds that are as strong or stronger than those found at 700mb level, especially during the phase of rapid intensification. The flight level/surface wind reduction factor in this case is likely not 80-90%, but more like 95% to 115%. I believe that the operational practices of NHC definitely have changed due to such findings. If storms like Matthew were existed back to ten years ago, they probably wouldn't be granted CAT5 due to high central pressures and lower flight level winds, and Irma wouldn't have a record breaking 37 consecutive hours of 160kt intensity either.

For reference, here is the part of Hurricane Felix report regarding its peak intensity:
The maximum intensity of Felix near 0000-0600 UTC 3 September has greater than normal uncertainty. A NOAA Hurricane Hunter aircraft estimated a 163 kt surface wind in the northeastern eyewall using the Stepped Frequency Microwave Radiometer (SFMR), while a dropsonde in the vicinity measured winds of 195 kt about 120 m above the surface. (The sonde subsequently fell into the eye, which significantly reduced the low-level layer-average winds that are normally used to assess the surface winds.) Examination of these SFMR data by personnel at the NOAA Hurricane Research Division found no obvious problems with signal contamination by rain or graupel. However, the observed flight-level winds (152 kt at 700 mb), aircraft Doppler radar data, central pressure, and satellite signature do not support an intensity of 160-165 kt. Detailed data from the sonde show that the extreme winds were confined to the lowest 200 m, and that it made a left turn into the eye while passing through this layer. This suggests that the sonde and the SFMR sampled a small-scale feature in the eyewall that likely was not representative of the true strength of Felix. As the plane passed through the southeastern eyewall, the SFMR estimated surface winds of 142 kt, while a dropsonde reported low-level layer averages supporting 130-140 kt surface sustained winds. Given the westward motion at the time, it is likely that the stronger winds existed in the northern eyewall. The maximum intensity is set at 150 kt based on a blend of these data, and this could be conservative.

As shown above, the reliable 163kt SFMR measurement was discounted due to lower flight level wind (152kt at 700mb), high central pressure(~930mb), and less impressive satellite presentation(relatively warm CDO), which has not been the case in Irma when 160kt SFMR wind was found while the peak flight level wind was only 151kt from the same flight. A IR imagery comparison of Felix and Irma at the time of ~160kt SFMR report is shown below.

Image


The infamous dropsonde that measured 168kt surface wind in Maria is also pretty telling, as the low level winds were significantly higher(50-60kts higher!) than winds at 700-850mb flight level.
Again, one could ague that Maria reached a peak intensity of 155-160kt based the average wind over lowest 150gpm. I think an upgrade to 155kt by NHC is possible in post-season analysis.

Image


My personal intensity revision for past Atlantic hurricanes with recon based on assumptions derived from SFMR or dropsonde data:

Gilbert - 160kt -> 170kt
Isabel 145kt -> 150kt
Rita - 155kt -> 165kt
Wilma 160kt -> 175kt
Felix 150kt -> 165kt
Jose 135kt -> 145kt
Maria 150kt -> 155kt
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Re: Discussion of Intense Tropical Cyclones

#174 Postby 1900hurricane » Sun Oct 01, 2017 9:19 pm

Yep, there is certainly much yet to learn, but we've made some big strides over the past several years. Observations in the intense system listed above have been particularly eye opening. Without recon, we likely wouldn't have realized how intense some of these systems actually were. As alluded to by supercane4867 a few posts previous, systems probably need to be supplemented, sometimes heavily, with microwave data beginning around the DT 6.5 area when using the Dvorak Technique. Irma '17 is a particularly infamous example of recon finding a tropical cyclone stronger than expected when using IR intensity estimates like the Dvorak Technique and ADT, but it can go the other way too.

Image

The system above appears to be in the T7.0 range or thereabouts. The cloud tops are impressively cold with a cold medium grey surrounding shade and the eye is pretty deep in the off-white color shade. Seems like it should at least in the category 5 ballpark, right? However, recon only found surface winds of 110 kt! Surprising, right? However, when cross-referencing with the closest microwave pass (below), 110 kt actually seems like an ok fit. This system is Karl '10, by the way.

Image

As far as objective intensity estimations go, SATCON appears to be the closest to the winning formula at the moment in my opinion. SATCON relies heavily on microwave data and ran much closer to the measured peak intensities for Irma, Jose, and Maria than the IR based estimates alone. It's not perfect though. Microwave data that SATCON uses often lags real-time slightly, which delays intensity estimates. The microwave data itself is also a little inconsistent and somewhat coarse temporally, which can limit it in scenarios with quickly changing intensities. As an example of this, SATCON did not capture Maria's initial peak just prior to its landfall in Dominica well (pictured below). SATCON may also be poor with unraveling post-peak systems in the subtropics, running as much as 30 kt above actual intensity at one point with Maria. This is probably a scenario in which an operational forecaster can realize that the estimate is unrealistic though, but this also highlights the ever present need for human data interpretation in meteorology.

Image

I've been a little skeptical with SATCON in the past, particularly with Meranti '16, but aside from what I mentioned above, I'm finding less and less to complain about at the high intensities. I guess it's no surprise SATCON went so nuts with the system when microwave imagery was perhaps the most impressive I've ever seen.

Image
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Re: Discussion of Intense Tropical Cyclones

#175 Postby Alyono » Sun Oct 01, 2017 9:43 pm

supercane4867 wrote:I think the most important takeaway from recon observation of CAT5s in recent years is that the flight level to surface wind relationship is more complex than we thought.


It's not more complex. The Black et al paper gave a range of reduction factors from 700mb to the surface of .6 to 1.2. What we've been able to tell conclusively in the past couple of years with a relatively large dataset is that for storms in the deep tropics, or moving westward under a strong ridge in a purely barotropic environment (and not undergoing an EWRC), the surface winds are usually equal to or greater than the flight level winds.

This is why I believe Andrew was 170 kts at landfall, not the 145 that reanalysis found (the initial 25 kts failed almost any basic science test as a gradient wind analysis found winds at 140 kts)
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Re: Discussion of Intense Tropical Cyclones

#176 Postby 1900hurricane » Sun Oct 01, 2017 10:17 pm

Alyono wrote:
supercane4867 wrote:I think the most important takeaway from recon observation of CAT5s in recent years is that the flight level to surface wind relationship is more complex than we thought.


It's not more complex. The Black et al paper gave a range of reduction factors from 700mb to the surface of .6 to 1.2. What we've been able to tell conclusively in the past couple of years with a relatively large dataset is that for storms in the deep tropics, or moving westward under a strong ridge in a purely barotropic environment (and not undergoing an EWRC), the surface winds are usually equal to or greater than the flight level winds.

This is why I believe Andrew was 170 kts at landfall, not the 145 that reanalysis found (the initial 25 kts failed almost any basic science test as a gradient wind analysis found winds at 140 kts)

I think this is not the paper co-written by Michael Black that you're referring to (he's written a few), but here is the paper he co-authored with James Franklin and Krystal Valde that more or less settled on the 0.9 reduction from 700 mb winds. Curiously enough, it specifically mentions a case from Mitch '98 where dropsondes measured significantly stronger winds near the surface than were found at 700 mb. From the paper:

Image

Figure 2. Wind speed profile from the eyewall of Hurricane Mitch at 2337 UTC 27 October 1998. Vertical lines indicate the boundaries of Saffir-Simpson Hurricane Scale categories. Sloping dashed line indicates the peak flight-level wind found during the reconnaissance flight, and its conversion to an assumed surface wind using a 0.9 reduction factor.
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Re: Discussion of Intense Tropical Cyclones

#177 Postby 1900hurricane » Sun Oct 01, 2017 10:29 pm

Hammy wrote::uarrow: Where do you access the imagery?

It's probably not the only way you can access it, but I view it through HURSAT.
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Re: Discussion of Intense Tropical Cyclones

#178 Postby tatertawt24 » Mon Oct 02, 2017 2:42 pm

supercane4867 wrote:I think the most important takeaway from recon observation of CAT5s in recent years is that the flight level to surface wind relationship is more complex than we thought. Operational practices of NHC in the past typically use the standard 90% reduction factor to estimate surface windspeed from 700mb flight level winds. The introduction of SFMR measurements has lead to new insights on surface windspeed of intense TCs, but it wasn't available on USAF planes until 2007 and didn't become the main basis for assigning peak intensity until mid 2010s. Lack of SMFR presence at peak intensities is very common back to the hyperactive seasons of 2003-05. Nearly all recon flights into recent CAT5s including Felix, Megi, Patricia, Matthew, Irma, and Maria have found the surface winds measured by SFMR and dropsonde were equal or greater than those measured at flight levels. Data indicates the dynamics of these top CAT5 storms may generate surface winds that are as strong or stronger than those found at 700mb level, especially during the phase of rapid intensification. The flight level/surface wind reduction factor in this case is likely not 80-90%, but more like 95% to 115%. I believe that the operational practices of NHC definitely have changed due to such findings. If storms like Matthew were existed back to ten years ago, they probably wouldn't be granted CAT5 due to high central pressures and lower flight level winds, and Irma wouldn't have a record breaking 37 consecutive hours of 160kt intensity either.

For reference, here is the part of Hurricane Felix report regarding its peak intensity:
The maximum intensity of Felix near 0000-0600 UTC 3 September has greater than normal uncertainty. A NOAA Hurricane Hunter aircraft estimated a 163 kt surface wind in the northeastern eyewall using the Stepped Frequency Microwave Radiometer (SFMR), while a dropsonde in the vicinity measured winds of 195 kt about 120 m above the surface. (The sonde subsequently fell into the eye, which significantly reduced the low-level layer-average winds that are normally used to assess the surface winds.) Examination of these SFMR data by personnel at the NOAA Hurricane Research Division found no obvious problems with signal contamination by rain or graupel. However, the observed flight-level winds (152 kt at 700 mb), aircraft Doppler radar data, central pressure, and satellite signature do not support an intensity of 160-165 kt. Detailed data from the sonde show that the extreme winds were confined to the lowest 200 m, and that it made a left turn into the eye while passing through this layer. This suggests that the sonde and the SFMR sampled a small-scale feature in the eyewall that likely was not representative of the true strength of Felix. As the plane passed through the southeastern eyewall, the SFMR estimated surface winds of 142 kt, while a dropsonde reported low-level layer averages supporting 130-140 kt surface sustained winds. Given the westward motion at the time, it is likely that the stronger winds existed in the northern eyewall. The maximum intensity is set at 150 kt based on a blend of these data, and this could be conservative.

As shown above, the reliable 163kt SFMR measurement was discounted due to lower flight level wind (152kt at 700mb), high central pressure(~930mb), and less impressive satellite presentation(relatively warm CDO), which has not been the case in Irma when 160kt SFMR wind was found while the peak flight level wind was only 151kt from the same flight. A IR imagery comparison of Felix and Irma at the time of ~160kt SFMR report is shown below.

Image


The infamous dropsonde that measured 168kt surface wind in Maria is also pretty telling, as the low level winds were significantly higher(50-60kts higher!) than winds at 700-850mb flight level.
Again, one could ague that Maria reached a peak intensity of 155-160kt based the average wind over lowest 150gpm. I think an upgrade to 155kt by NHC is possible in post-season analysis.

Image


My personal intensity revision for past Atlantic hurricanes with recon based on assumptions derived from SFMR or dropsonde data:

Gilbert - 160kt -> 170kt
Isabel 145kt -> 150kt
Rita - 155kt -> 165kt
Wilma 160kt -> 175kt
Felix 150kt -> 165kt
Jose 135kt -> 145kt
Maria 150kt -> 155kt


Interesting. Could the difference between Felix and Irma's IR presentation be technological? Like, could it just be more accurate today and thus less likely to pick up solid reds like with Felix?
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supercane4867
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Re: Discussion of Intense Tropical Cyclones

#179 Postby supercane4867 » Mon Oct 02, 2017 7:13 pm

tatertawt24 wrote:Interesting. Could the difference between Felix and Irma's IR presentation be technological? Like, could it just be more accurate today and thus less likely to pick up solid reds like with Felix?

Not likely, since our weather satellites have been able to accurately monitor cloudtop temperatures for the past few decades.
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Re: Discussion of Intense Tropical Cyclones

#180 Postby supercane4867 » Mon Oct 02, 2017 7:14 pm

The SPAC paper mentioned in earlier posts is now freely accessible, featuring a thorough analysis of Cyclone Hina with rare high quality satellite imagery.
Re-analysis data has Hina at DT7.5 for 24 hours and DT8.0 for 12 hours, such persistence time of T7.5 or greater is competitive with Haiyan which is extremely impressive.

Image

Image


Interestingly, the paper mentioned that Cyclone Anne of 1988 reached T8.0 as well. The satellite presentation is quite hyperbolic.

Image
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