Cat 5 Major Hurricane Patricia

[wxmx]

Thanks Maru for all the info provided. Regarding your question,I wouldn't know if a correction can be done, but if the anemometer has no other physical damage, other than the tilting, it may be possible. Do you know the exact time the anemometer tilted?

Also, I would think that the anemometer has a margin where readings above 250km/h might be accurately recorded, but tests would have to be performed to check that. But even if that margin exists it seems highly unlikely the 185mph sustained wind will be confirmed.

[Roger Smith]

Two clues that remain open to investigation:

 

1. Inspection of the conditions at the biological research station where the weather station is located, and if they have on-site staff, did they ride out the storm there or did they go home somewhere nearby, if so, where and what happened there?

 

2. On the coast just southeast of Costa Cayeres and south of Josh's location (EZ) there is a large concrete structure called the Copa del Sol on an exposed point. Inspection of the adjacent trees and staircases might provide some clues, or if the large concrete structure was moved or damaged substantially that might tell people something too.

 

As to the pressure record at the weather station (similar to Josh's report) being inconclusive, I would consider the pressure falls fairly extreme and in terms of weakening over the ocean before landfall, it was way into the cat-5 zone before that began to happen, so we do have some room for weakening and yet achieve cat-5 landfall. My opinion is that this may have existed very briefly and over very small patches of land while cat-4 probably applies to EZ from the video evidence and later pictures.

 

We may never get a definitive answer to this and the large-scale picture is one everyone agrees on, a very powerful hurricane over the Pacific rapidly weakened at or just after landfall and that, combined with the luck of the draw on exact landfall location, probably prevented major devastation and casualties. Imagine if this same landfall had been 20 miles further west, Punta Perula would have been swept away no doubt by storm surge if not cat-4/5 winds in its very exposed location. The developments at Costa Cayeres are a bit higher above the ocean and the irregular shoreline there probably dispersed some of the surge height.

[Maru Gonzalez]

Two clues that remain open to investigation:

 

1. Inspection of the conditions at the biological research station where the weather station is located, and if they have on-site staff, did they ride out the storm there or did they go home somewhere nearby, if so, where and what happened there?

 

2. On the coast just southeast of Costa Cayeres and south of Josh's location (EZ) there is a large concrete structure called the Copa del Sol on an exposed point. Inspection of the adjacent trees and staircases might provide some clues, or if the large concrete structure was moved or damaged substantially that might tell people something too.

 

As to the pressure record at the weather station (similar to Josh's report) being inconclusive, I would consider the pressure falls fairly extreme and in terms of weakening over the ocean before landfall, it was way into the cat-5 zone before that began to happen, so we do have some room for weakening and yet achieve cat-5 landfall. My opinion is that this may have existed very briefly and over very small patches of land while cat-4 probably applies to EZ from the video evidence and later pictures.

 

We may never get a definitive answer to this and the large-scale picture is one everyone agrees on, a very powerful hurricane over the Pacific rapidly weakened at or just after landfall and that, combined with the luck of the draw on exact landfall location, probably prevented major devastation and casualties. Imagine if this same landfall had been 20 miles further west, Punta Perula would have been swept away no doubt by storm surge if not cat-4/5 winds in its very exposed location. The developments at Costa Cayeres are a bit higher above the ocean and the irregular shoreline there probably dispersed some of the surge height.

 

I can provide some of the info you need, directly on the forum or through the moderator, who kindly replied to my previous post. I am on the last few minutes of wifi available here at the Biological Station (the electricity last only a couple of hours every day), but I will post pictures on my next period online.

[bdgwx]

By the way, I should have mentioned this earlier, but I believe the pressure readings in the data dump from CCXJ1 are station pressure. I verified this by comparing the exported csv to their webpage which lists both station pressure and sea level pressure. The MSLP adjustment at the time was was roughly +10mb based on a 100m height and 23C temperature. So that 937mb (27.68) reading is 947mb when reduced to sea level. The 211 mph gust was colocated with a 963mb sea level pressure. It would be good if someone else could double check that though.

[winterymix]

RM Young ultrasonic sensor

 

I can provide some of the info you need, directly on the forum or through the moderator, who kindly replied to my previous post. I am on the last few minutes of wifi available here at the Biological Station (the electricity last only a couple of hours every day), but I will post pictures on my next period online.

If I convert m/s to mph, this Young sensor is good to 156 mph. 

I guess it will be up to the NHC to decide if they trust extrapolating in order to accept or not accept the

wind speeds recorded at your station.

[Amped]

Hello everyone,

This is my first post and will be long. I actually live and work at the Chamela Biological Station where the wind readings you all have been discussing come from, so I thought I could add something to this most interesting thread. I have followed some of the threads in this forum since Jova made its landfall very close to the station four years ago.

The met station is part of a system installed in federal protected lands by CONAGUA and CONANP, the government agencies in charge of the national meteorological system and the national protected areas systems, respectively. The biology station is located at the top of a hill, at an altitude of around 95 meters asl, and the anemometer is approximately 9.7 m above ground. The station was situated, as some of you have stated, on the NW quadrant of Patricia at landfall. The anemometer in question is a RM Young ultrasonic sensor (SDI-UWS-RMY), and I did suspected its readings since Patricia. Before the hurricane, the station had been giving reliable information, but at some point during the storm the sensor got tilted considerably (I thought it would not survive). I attach a picture of it. Besides that, the range of operation goes from 0 to 70 m/s, so anything above 252 km/h cannot be sensed by this thing. I downloaded the data as soon as I got to the station on the 24th, and I also noticed the red flags. I think the crazy readings (in the thousands of kph) might just be malfunctioning, and I agree that the very high winds sustained for an inordinate amount of time look really bad. All data from 18:20 to 19:40 might be garbage, and of course the anemometer remained tilted, so any data since 18:20 are affected. The pressure readings I believe.

Here is where I will frankly abuse this forum where I never contribute and may tap into your collective wisdom: does anyone think it might be scientifically sounded to perform a correction of the data <250 km/h based on some sort of empirical assessment of the bias (i.e. wind blowing on the tilted and leveled anemometer), or on calculations of such bias based on the tilt angle and the azimuth? I hope the question makes sense.

Finally I want to share this with you all: I was going to stay at the station with my husband and my dog during the storm, and you guys scared the hell out of me when you started to advise Josh to get out the area. The station is first rate (one of the first of its kind in Latin America, it is visited by people all over the world), the buildings are really solid (many big windows though), but the comments on this thing being something like an EF4/EF5 made me doubt our ability to come out of this monster unscathed. I will send pictures if you are interested in the kind of damage we sustained, but I can say it is considerable, the biology station and the forest look very different now after the hurricane. I have not seen signs of debarking, but I have not been able to go much into the forest yet.

Please take into account I am not a meteorologist, so I won´t be able to answer questions you may have (although I am somewhat familiar with the region). Just a humble biologist here, I do research on turbulent CO2 exchange in the tropical dry forest, so naturally weather and hurricanes and their effect on vegetation fascinate me. I really enjoy and learn a lot reading this forum.

Thanks!

P.S. I apologize in advance if people have some questions and I do not answer soon. We only have electricity and access to internet for a couple of hours every day since dear Patty, and reading all your posts today consumed most of this time.

P.S.2. I swear I did not hold a hair dryer to the anemometer!

 

Thanks for the new info on this station. The best thing to do might be to contact the manufacturer. It is not even supposed to read anything above 167.8mph according to the specs, so only they might know how it gave readings higher than that. I think doing calculations won't help much, because it will probably need to be re-calibrated as is to verify the readings. Also, it's an ultrasonic sensor, so the calculations may not be that simple.

[winterymix]

Ideally, one of those sensors should be mounted on the same rig and placed in

a wind tunnel. The wind speed can then be increased until the sensor reaches the

same angle of deviation.

What would this us? At the very least, we would know the minimal wind speed to

tilt the sensor on that particular mount.

[bdgwx]

Great information Maru. According to the installation manual for some of the Young products (I couldn't find the manual for that specific model) the junction box should face south. Which direction is it facing now? Also, how much did it bend down? Can you estimate the bend angle? It's hard to tell from the picture. 

 

Anybody know...how sensitive are these ultrasonic instruments to changes in vertical angle?

 

I agree about getting the manufacturer involved. They have an easy to find contact information page on their website.

[Ginx snewx]

How cool is it that we got first hand info on this. Thanks Maru. Glad you decided to leave. Good choice.

[wxeyeNH]

I second Ginx post.  Just great info on the station and instrumentation.  Thanks Maru. Maybe someone from the manufacture or NHC or Mexican Government could lead an investigation before the instrument angle is altered to see if somehow the conditions could be replicated since its data is the only wind data we have at the coast.  Replication in a wind tunnel with a known wind spead might be a good key to determine if we had a strong Cat 4 or 5 at landfall.

[Roger Smith]

By the way, I should have mentioned this earlier, but I believe the pressure readings in the data dump from CCXJ1 are station pressure. I verified this by comparing the exported csv to their webpage which lists both station pressure and sea level pressure. The MSLP adjustment at the time was was roughly +10mb based on a 100m height and 23C temperature. So that 937mb (27.68) reading is 947mb when reduced to sea level. The 211 mph gust was colocated with a 963mb sea level pressure. It would be good if someone else could double check that though.

 

I think that was on the first screen capture way back in this thread. Something like this -- minimum station pressure 27.6 inches, minimum sea level pressure 27.9 inches. At the rate the pressures were changing, maybe 27.5 and 27.8 could be used as plausible extreme lows.

 

... Maru, thanks for posting. If time permits, can you tell us what the Copa del Sol on the coast is all about? And is it still there?

[HurricaneJosh]

Hi, everybody!

 

Whoa-- it's been a while since I've posted here. Nice to see all the old handles.

 

A quick note: I do not assign my own intensities to storms. I am calling PATRICIA a Cat-5 landfall because that is what the NHC has officially called it. My calling it a Cat 5 is not me expressing an opinion-- it is me relaying the official NHC position. And that's all there is to it. If in postanalysis the NHC downgrades it to a Cat 4, then I will call it a Cat 4. I always defer to their verdicts and I don't push an alternate or competing viewpoint to the NHC's. iCyclone uses only NHC intensities.

 

I have occasionally disagreed with them behind the scenes. For example, I believed ODILE was a 115-kt Cat 4 when it hit Los Cabos, and I sent them a detailed write-up-- including equations, etc.-- making my case. In the end, they decided to keep it a Cat 3, and so that is how I refer to ODILE in public communications-- a Cat 3, as per the NHC's official categorization.

 

Re: PATRICIA, specifically... I have heard all the arguments about why it was a Cat 5 vs. why it was a Cat 4. There are some interesting arguments both ways. I look forward to hearing the NHC's final verdict.

 

Of course my data will play a part in their analysis-- and the signals from those data are mixed.

 

I apparently scraped the edge of the eye, so my 937.8 mb was not a central pressure but close. The sky brightened and I saw bits of blue sky, but the wind never dropped below 40 or 50 kt, suggesting the central pressure was maybe near 930 mb or so-- i.e., higher than the NHC's operational estimate.

 

On the other hand, the pressure gradient in PATRICIA's core was off the f*cking charts. As the center moved away, the pressure rose 31 mb in 26 minutes (!!!) and 15 mb within 9 minutes. Using a forward speed of 15 mph and making an allowance for the weakening trend yields a pressure gradient of 6 or 7 mb/mi-- which is just sick. I've never measured such an explosive gradient. (For example, as ODILE's center moved away from me, the pressure rose 30 mb in an 1 hour (more than twice the time as the same rise in PATRICIA), and that storm was moving faster-- and I thought that was intense...) And it's interesting that the most violent winds in the back eyewall-- winds that tore our hotel apart-- happened during this explosive pressure recovery. PATRICIA was of course on a weakening trend at landfall, but it was not a KATRINA-type deal, where the pressure field flattened out and the wind radii dramatically expanded. PATRICIA was still a tight-core system-- as evidence not just by the crazy core gradient I observed, but by the fact that the peak winds were very violent, confined very close to the center, and of relatively short duration.

 

Anyhoo, Re: the official category, I'm not pushing one viewpoint or another-- just sharing some of the factors here. I am looking forward to the NHC's verdict. Until postanalysis is completed, I will refer to PATRICIA as a Cat-5 landfall and chase, as per the official operational intensity.

 

P.S. The above having been said, I absolutely will express an opinion about how this storm "felt" compared to the other 24 hurricane cores I've been in. (Yes, PATRICIA was No. 25.) And I can confidently say PATRICIA was way up there-- my worst or second-worst in terms of winds.

[ncforecaster89]

Hello everyone,

This is my first post and will be long. I actually live and work at the Chamela Biological Station where the wind readings you all have been discussing come from, so I thought I could add something to this most interesting thread. I have followed some of the threads in this forum since Jova made its landfall very close to the station four years ago.

The met station is part of a system installed in federal protected lands by CONAGUA and CONANP, the government agencies in charge of the national meteorological system and the national protected areas systems, respectively. The biology station is located at the top of a hill, at an altitude of around 95 meters asl, and the anemometer is approximately 9.7 m above ground. The station was situated, as some of you have stated, on the NW quadrant of Patricia at landfall. The anemometer in question is a RM Young ultrasonic sensor (SDI-UWS-RMY), and I did suspected its readings since Patricia. Before the hurricane, the station had been giving reliable information, but at some point during the storm the sensor got tilted considerably (I thought it would not survive). I attach a picture of it. Besides that, the range of operation goes from 0 to 70 m/s, so anything above 252 km/h cannot be sensed by this thing. I downloaded the data as soon as I got to the station on the 24th, and I also noticed the red flags. I think the crazy readings (in the thousands of kph) might just be malfunctioning, and I agree that the very high winds sustained for an inordinate amount of time look really bad. All data from 18:20 to 19:40 might be garbage, and of course the anemometer remained tilted, so any data since 18:20 are affected. The pressure readings I believe.

Here is where I will frankly abuse this forum where I never contribute and may tap into your collective wisdom: does anyone think it might be scientifically sounded to perform a correction of the data <250 km/h based on some sort of empirical assessment of the bias (i.e. wind blowing on the tilted and leveled anemometer), or on calculations of such bias based on the tilt angle and the azimuth? I hope the question makes sense.

Finally I want to share this with you all: I was going to stay at the station with my husband and my dog during the storm, and you guys scared the hell out of me when you started to advise Josh to get out the area. The station is first rate (one of the first of its kind in Latin America, it is visited by people all over the world), the buildings are really solid (many big windows though), but the comments on this thing being something like an EF4/EF5 made me doubt our ability to come out of this monster unscathed. I will send pictures if you are interested in the kind of damage we sustained, but I can say it is considerable, the biology station and the forest look very different now after the hurricane. I have not seen signs of debarking, but I have not been able to go much into the forest yet.

Please take into account I am not a meteorologist, so I won´t be able to answer questions you may have (although I am somewhat familiar with the region). Just a humble biologist here, I do research on turbulent CO2 exchange in the tropical dry forest, so naturally weather and hurricanes and their effect on vegetation fascinate me. I really enjoy and learn a lot reading this forum.

Thanks!

P.S. I apologize in advance if people have some questions and I do not answer soon. We only have electricity and access to internet for a couple of hours every day since dear Patty, and reading all your posts today consumed most of this time.

P.S.2. I swear I did not hold a hair dryer to the anemometer!

Hi Maru! Thanks so much for taking the time to share all of the important information contained in your post. More importantly, we are all most thankful you survived this intense hurricane, and I pray the area recovers as soon as possible.

Your personal observations will be a huge benefit to the NHC in determining the best intensity estimate for Patricia at landfall. Thanks again!

[ncforecaster89]

As to the pressure record at the weather station (similar to Josh's report) being inconclusive, I would consider the pressure falls fairly extreme and in terms of weakening over the ocean before landfall, it was way into the cat-5 zone before that began to happen, so we do have some room for weakening and yet achieve cat-5 landfall. My opinion is that this may have existed very briefly and over very small patches of land while cat-4 probably applies to EZ from the video evidence and later pictures.

We may never get a definitive answer to this and the large-scale picture is one everyone agrees on, a very powerful hurricane over the Pacific rapidly weakened at or just after landfall and that, combined with the luck of the draw on exact landfall location, probably prevented major devastation and casualties. Imagine if this same landfall had been 20 miles further west, Punta Perula would have been swept away no doubt by storm surge if not cat-4/5 winds in its very exposed location. The developments at Costa Cayeres are a bit higher above the ocean and the irregular shoreline there probably dispersed some of the surge height.

Agree with the main points of your post with the exception of the fact that Patricia was rapidly weakening a good 5 hours plus prior to landfall (not just simply at or just after it). In my own humble opinion (based on the data), that most definitely gives it time to weaken below Cat 5 intensity before landfall...and it's highly unlikely it retained category-five strength to the coast.

[ncforecaster89]

Hi, everybody!

Whoa-- it's been a while since I've posted here. Nice to see all the old handles.

A quick note: I do not assign my own intensities to storms. I am calling PATRICIA a Cat-5 landfall because that is what the NHC has officially called it. My calling it a Cat 5 is not me expressing an opinion-- it is me relaying the official NHC position. And that's all there is to it. If in postanalysis the NHC downgrades it to a Cat 4, then I will call it a Cat 4. I always defer to their verdicts and I don't push an alternate or competing viewpoint to the NHC's. iCyclone uses only NHC intensities.

I have occasionally disagreed with them behind the scenes. For example, I believed ODILE was a 115-kt Cat 4 when it hit Los Cabos, and I sent them a detailed write-up-- including equations, etc.-- making my case. In the end, they decided to keep it a Cat 3, and so that is how I refer to ODILE in public communications-- a Cat 3, as per the NHC's official categorization.

Re: PATRICIA, specifically... I have heard all the arguments about why it was a Cat 5 vs. why it was a Cat 4. There are some interesting arguments both ways. I look forward to hearing the NHC's final verdict.

Of course my data will play a part in their analysis-- and the signals from those data are mixed.

I apparently scraped the edge of the eye, so my 937.8 mb was not a central pressure but close. The sky brightened and I saw bits of blue sky, but the wind never dropped below 40 or 50 kt, suggesting the central pressure was maybe near 930 mb or so-- i.e., higher than the NHC's operational estimate.

On the other hand, the pressure gradient in PATRICIA's core was off the f*cking charts. As the center moved away, the pressure rose 31 mb in 26 minutes (!!!) and 15 mb within 9 minutes. Using a forward speed of 15 mph and making an allowance for the weakening trend yields a pressure gradient of 6 or 7 mb/mi-- which is just sick. I've never measured such an explosive gradient. For example, as ODILE's center moved away from me, the pressure rose 30 mb in an 1 hour, and that storm was moving faster-- and I thought that was intense... And it's interesting that the most violent winds in the back eyewall-- winds that tore our hotel apart-- happened during this explosive pressure recovery. PATRICIA was of course on a weakening trend at landfall, but it was not a KATRINA-type deal, where the pressure field flattened out and the wind radii dramatically expanded. PATRICIA was still a tight-core system-- as evidence not just by the crazy core gradient I observed, but by the fact that the peak winds were very violent, confined very close to the center, and of relatively short duration.

Anyhoo, Re: the official category, I'm not pushing one viewpoint or another-- just sharing some of the factors here. I am looking forward to the NHC's verdict. Until postanalysis is completed, I will refer to PATRICIA as a Cat-5 landfall and chase, as per the official operational intensity.

P.S. The above having been said, I absolutely will express an opinion about how this storm "felt" compared to the other 24 hurricane cores I've been in. (Yes, PATRICIA was No. 25.) And I can confidently say PATRICIA was way up there-- my worst or second-worst in terms of winds.

Hi Josh! Thanks for taking the time to share and clarify your own personal views regarding your experience with this historic hurricane landfall.

More importantly, we are obviously most thankful you survived this incredible chase experience without injury.

As I've stated numerous times, your obs are a huge benefit to the NHC in assisting them with providing their best estimated maximum sustained 1-minute wind speed at landfall for Patricia. We are in excellent agreement on the likely landfalling central pressure being around 930 mb. Likewise, it is indisputable that Patricia remained a very intense hurricane with a corresponding extreme pressure gradient; albeit not as extreme as it once was at peak intensity.

After viewing the video clip you provided to TWC, I'd personally estimate that those were very likely category-four conditions and arguably some of the most impressive wind speeds captured on film. A truly intense and historic chase event. Well done!

[eurojosh]

Hi, everybody!

 

Whoa-- it's been a while since I've posted here. Nice to see all the old handles.

 

 

 

Hello everyone,

This is my first post and will be long. I actually live and work at the Chamela Biological Station where the wind readings you all have been discussing come from, so I thought I could add something to this most interesting thread. 

 

 

 

 

AmericanWx is a truly amazing forum.

[MN Transplant]

AmericanWx is a truly amazing forum.

 

I was thinking the same.  Thanks to both Maru and Josh for relaying their experiences!

[DTWXRISK]

 bingo   right there   

I apparently scraped the edge of the eye, so my 937.8 mb was not a central pressure but close. The sky brightened and I saw bits of blue sky, but the wind never dropped below 40 or 50 kt, suggesting the central pressure was maybe near 930 mb or so-- i.e., higher than the NHC's operational estimate.

[DTWXRISK]

pure  speculation

Agree with the main points of your post with the exception of the fact that Patricia was rapidly weakening a good 5 hours plus prior to landfall (not just simply at or just after it). In my own humble opinion (based on the data), that most definitely gives it time to weaken below Cat 5 intensity before landfall...and it's highly unlikely it retained category-five strength to the coast.

[DTWXRISK]

   this is    REALLY  piss poor reasoning on so many levels  I dont know where to begin
   

1    winds greater than 155 mph where is  tiny  area   far smaller  than  with we saw with Andrew 

2   absence off  evidence   is NOT  conclusive    ESPECIALLY   given other factors 

 

3 Josh has shown  that  his 937 mb reading   was  NOT  in the    eye  and his winds  never droped  below 40 knots 
 

 4  given the  extreme  PG  which  DID  exist   it is  likely  that  the  lowest MSLP  was  significantly  lower than anything Josh
recorded 

 

 

Although I respect your well thought out opinion, the fact that Patricia was rapidly weakening prior to landfall...not just after it came ashore (which obviously greatly exacerbated that rapid rate of weakening) easily explains the rapid rises in observed pressure at both locations you noted.

As a result, the theorized pressure-gradient you and Josh suggest is possible (or actually occurred) would not support a category-five MSW. So far, there remains no reliable data, or any evidence, that category-five conditions were experienced anywhere on the coast at landfall. If there had been, there would be no room for this debate and the resultant damage would be obvious.

[ineedsnow]

By far the best forum glad you made it out ok josh! Will be interesting to see what the nhc final outcome will be!

[ncforecaster89]

pure speculation

And so is your opinion.

[ncforecaster89]

this is REALLY piss poor reasoning on so many levels I dont know where to begin

1 winds greater than 155 mph where is tiny area far smaller than with we saw with Andrew

2 absence off evidence is NOT conclusive ESPECIALLY given other factors

3 Josh has shown that his 937 mb reading was NOT in the eye and his winds never droped below 40 knots

4 given the extreme PG which DID exist it is likely that the lowest MSLP was significantly lower than anything Josh

recorded

Hey DT...talk about "piss-poor reasoning!"

1) First, there's no evidence or data that suggests unequivocally that Patricia had any MSWs greater than 156 mph (winds actually must exceed 156 mph for a category-five designation) anywhere in the eyewall at landfall.

2) What are you even saying here? Evidence encompasses everything to include any data suggesting the prospect of category-five intensity MSW at landfall.

3) Do you even know how some of the inner-core dynamics work inside a rapidly weakening hurricane...especially in the case of Patricia at landfall? If you do...then you understand that the eye was filling at an astonishing rate whereby the inner-core was collapsing in on itself. As a result, the conditions within the eye would NOT be as tranquil as otherwise would've been the case. This easily explains why Josh wouldn't be able to see any more reduction in the winds (at the apparent edge of the eye) than he did. It's even conceivable he may have gotten inside the eye, in reality, based on his description of the conditions at that time, and considering the center observed on satellite could've theoretically been off by 1-2 nm.

Although we naturally assume that winds not dropping below gale-force meant he was just outside the eye, the reality is he still could've very well gotten inside of it...even if not the absolute center. This is especially true given that he was only 2 nm E of the eye based on the NHC advisory at landfall.

All that being said, his very close proximity to the absolute center of the eye virtually assures a central pressure no lower than 928 mb at landfall and more likely 930 mb.

4) I've not once denied that there was a very steep pressure-gradient inside the eye of Patricia at landfall. That said, it's only conjecture to assume we can be absolutely sure just how extreme it actually was.

Regardless, we can be certain that it wasn't in the category (no pun intended) of that seen with an INTENSIFYING category-five hurricane, known as Andrew, at landfall in S FL in 1992. It has been determined that there was an immense pressure gradient of 36 mb at 4.25 nm (8.5 mb/nm) N of the eye. More impressively, the maximum extreme PG of 10 mb was found at the distance between 1.5 and 2.5 nm from the eye where the strongest winds were encountered during that strengthening 145 kt. H at landfall.

In contrast to Andrew, Patricia's eye was rapidly filling (while Andrew's even deepened just after coming ashore) with a mostly cloud-filled eye, according to satellite images.

To reiterate, there's nothing to suggest that Patricia was as intense as Andrew at landfall, and most likely came ashore with a MSW of 125-130 knots with a minimum central pressure around 930 mb.

The truth is that since we didn't have any RECON data inside the last 2.75 hours preceding landfall or any obs taken inside the center of the eye (to the best of our knowledge), any final determination by the NHC will always remain somewhat subjective and less certain than would've been the case, otherwise.

This in no way changes the reality that Patricia was highly likely the most intense hurricane landfall in EPAC recorded history!

[HurricaneJosh]

I am not going to get involved with this debate-- I really, seriously don't care to-- but please note my gradient calculations were preliminary-- based on simply eyeballing my data and picking a portion of the data that had an especially steep change in air pressure. I need to go over the data more closely this weekend. It could be that I find a 1-mi segment with an even steeper gradient than the 7 mb/mi I calculated. Also, the NHC is investigating this as well-- especially the Chamela data, to see if they might be partly usable. (There's a lot of internal discussion about this.)

 

No need to respond to this post with a counterargument because I am not making an argument or putting forth an opinion-- simply indicating that my calculations are preliminary.

 

Thanks.

[bdgwx]

Your insights and data regarding Patricia are incredibly useful Josh. If it weren't for you we would only have a fraction of the near-eye data. I'm sure a lot people here share my appreciation for your willingness to put yourself in harms way to collect the observations that you did.

[winterymix]

Hurricane Josh = Count de Millibars

[Maru Gonzalez]

Thanks gynx snewx, wxeyeNH, ncforecaster89 and all of you. The decision to leave the station was partly made on the info I was reading right here at the forum and the NHC advisories, so I am really grateful to you all.

News on the anemometer tilt: last Wednesday we were visited by people from CONAGUA, they got a message from NHC regarding the reliability of those readings and they came to check for themselves the state of the sensor and the whole station. They have thought about the wind tunnel test too, winterymix. The Biological station has already contacted people from the Engineering Institute at UNAM, they have a new wind tunnel and they are already in contact with CONAGUA and through them to NHC, either to perform the tests or to help them decide if it is worth doing. And yes, bdgwx, the anemometer was not only tilted, but the boom where it sits was rotated, so the junction box now it is due SW instead of S (approximately, they did not want me to climb the tower). Two of the three guy wires of the tower were loosen quite a bit, too. Luckily, they agree to leave the anemometer at its current position until more assessment is done. Hopefully the NHC interest exerts some pressure on them to stay on top of this.

I also looked at data (not publicly available, sorry) from a Met-One cup anemometer that is installed almost on the same spot, at around 4 m above ground. The highest reading there is 202 kph (125 mph) at 17:50 pm (CST), and it recorded winds >100 kph from 17:00 to 19:00. I understand these sensors have a lower upper range of measurement.

In the pictures you can see some of the damage we captured in the highway and what happened at the station too (hope the link works).

Finally, Roger Smith, regarding the Copa del Sol: It is a weird structure built by an excentric millionaire that owns a lot of land around here. It is supposed to serve as a point of contact with UFOs (!) and he celebrates some sort of re-energizing ritual up there. Excentricities apart, it is the largest concrete structure near the point of landfall, so we are trying to reach a biologist who works for this guy in order to visit the structure and report the damages it shows, if any. Truth is right now the communications with people in nearby villages is harder than reaching people like you, thousands of miles away.

Some towns around here took a big hit. They are mostly fishermen villages, the houses are poorly constructed, and most top roofs are gone and therefore all their stuff got damped and they lost the few things they had. Luckily, the abscense of flash floods meant that Emiliano Zapata and other towns that did very badly during Jova were spared of severe damage this time around, but people in poorer towns are suffering. On top of it, today and yesterday it has been raining and the Cuixmala river and others are swelling quickly. One can only hope there will be no flooding.

Going offline now. Read you later!

[HurricaneJosh]

I also looked at data (not publicly available, sorry) from a Met-One cup anemometer that is installed almost on the same spot, at around 4 m above ground. The highest reading there is 202 kph (125 mph) at 17:50 pm (CST), and it recorded winds >100 kph from 17:00 to 19:00. I understand these sensors have a lower upper range of measurement.

 

Hey, Maru-- thanks for the information-- it's very interesting. I was in Emiliano Zapata during the storm-- not far from you.

 

Do you mean 17:50 CST or CDT? Local time was CDT on the day of the hurricane.

[Maru Gonzalez]

Hey, Maru-- thanks for the information-- it's very interesting. I was in Emiliano Zapata during the storm-- not far from you.

 

Do you mean 17:50 CST or CDT? Local time was CDT on the day of the hurricane.

Hi Josh! so nice to get in contact with you. I know you were in EZ, I follow your work since Jova, I even took the liberty to show and explain your youtube video on Jova to locals during an Open House at the station in 2011. It was a talk about safety during hurricanes.

 

I understood from the guy in charge of the data it was CST. I know we were still on DT last Friday but it seems they keep their timestamps on winter time, but I will double check with him and will let you know.

 

Your chases are really cool!

[HurricaneJosh]

Hi Josh! so nice to get in contact with you. I know you were in EZ, I follow your work since Jova, I even took the liberty to show and explain your youtube video on Jova to locals during an Open House at the station in 2011. It was a talk about safety during hurricanes.

 

I understood from the guy in charge of the data it was CST. I know we were still on DT last Friday but it seems they keep their timestamps on winter time, but I will double check with him and will let you know.

 

Your chases are really cool!

 

Wow, thank you, Maru! That is so nice of you. And I'm so glad my JOVA video was helpful to your community. Thanks also for following my work.

 

It's been interesting to read your posts about the weather station there-- I'm so grateful to read you posts about it.

 

The highest winds at our location in Emiliano Zapata happened between 18:35 and about 19:00 CDT. The period of peak winds was very distinct where we were-- very sharply defined. It came and went like a tornado. So if your peak wind was 17:50 CDT, that would suggest a malfunction, whereas I suppose 17:50 CST (18:50 CDT) would make more sense. Is that peak wind sustained or gust? If gust, it seems very low-- even taking into account that the instrument height is very low (only 4 m instead of standard 10 m above ground).