Jump to content
  • Member Statistics

    17,508
    Total Members
    7,904
    Most Online
    joxey
    Newest Member
    joxey
    Joined

Chasing JOVA


Recommended Posts

  • Replies 439
  • Created
  • Last Reply

Aw, thanks, you guys. :)

P.S. Does *anyone* have (or have access to) the final microwave image(s)-- or any other porn-- from during or right before landfall? I'd pay money to see those. If you have 'em, please post 'em. Pretty please? :wub:

As you are well aware, there is not much in the way of documentation of EPAC hurricanes when they make landfall. Although you didn't get any wind data, your report is still important and I'm sure that NHC would be happy to have it.

Steve

Link to comment
Share on other sites

Josh, you have a good memory - better than mine - nice write up. In your photo that corona sign is laying out away from the overhang but you and I both know it was going to come down across the vehicle as our front end stuck out a few feet. Luckily it hit the over hanging roof first and that help our situation somewhat. I was watching it intently as the metal bent and twisted in the wind. I frantically angled the vehicle in that tight space just so if it came down it would miss the car - hopefully. I was driving out of there no matter what!

I hope your video of the tree coming down came out. It was nothing for an early gust of wind (blowing right to left) to knock down that big tree across the street - it went down in a second so easily. Then the wind shifted 180 degrees a few minutes later and blew that tree back upright momentarily before it fell back down when the gust subsided. Yeah, that's right - you had to see it to believe it. That big ole tree went right back up. That's when I knew we were in for a wild ride.

I must say at one point during probably the strongest gust I thought you might have been blown out from our spot. It's one thing to be in a car but quite another to be outside in the elements with the "stuff hitting the fan" or you. I was in the driver's seat and you were out my left window. The strongest gust came with a roar, the car shook from side to side, and everything was flying in our "protected space". I looked around behind me left & right and didn't see you. I yelled out - "Josh are you alright" and a few seconds later you appeared from behind the vehicle. I was on foot in downtown Punta Gorda for Charley and this is the first hurricane to give me flashbacks to that day. You were all wide eyed and lit up when you got back in the car.

For what it's worth, I looked up Emiliano Zapata, Jalisco, Mexico (there are a lot of Emiliano Zapatas in MX) on Wiki and it gave an elevation of 30 meters (98 feet) - pretty close to the GPS instrument reading.

Link to comment
Share on other sites

Josh, you have a good memory - better than mine - nice write up. In your photo that corona sign is laying out away from the overhang but you and I both know it was going to come down across the vehicle as our front end stuck out a few feet. Luckily it hit the over hanging roof first and that help our situation somewhat. I was watching it intently as the metal bent and twisted in the wind. I frantically angled the vehicle in that tight space just so if it came down it would miss the car - hopefully. I was driving out of there no matter what!

I hope your video of the tree coming down came out. It was nothing for an early gust of wind (blowing right to left) to knock down that big tree across the street - it went down in a second so easily. Then the wind shifted 180 degrees a few minutes later and blew that tree back upright momentarily before it fell back down when the gust subsided. Yeah, that's right - you had to see it to believe it. That big ole tree went right back up. That's when I knew we were in for a wild ride.

I must say at one point during probably the strongest gust I thought you might have been blown out from our spot. It's one thing to be in a car but quite another to be outside in the elements with the "stuff hitting the fan" or you. I was in the driver's seat and you were out my left window. The strongest gust came with a roar, the car shook from side to side, and everything was flying in our "protected space". I looked around behind me left & right and didn't see you. I yelled out - "Josh are you alright" and a few seconds later you appeared from behind the vehicle. I was on foot in downtown Punta Gorda for Charley and this is the first hurricane to give me flashbacks to that day. You were all wide eyed and lit up when you got back in the car.

For what it's worth, I looked up Emiliano Zapata, Jalisco, Mexico (there are a lot of Emiliano Zapatas in MX) on Wiki and it gave an elevation of 30 meters (98 feet) - pretty close to the GPS instrument reading.

Fantastic accounts by the both of you. I hope the video of a downed tree being blown back up is available, that would be momentous. Thank you both for sharing.

Link to comment
Share on other sites

Jim! So cool to see you post here! And thanks for sharing your perspective on that night. It's cool to have it in this thread-- makes it more complete.

For people who don't know Jim Edds... He is a top-notch weather videographer, and he's the one who shot my favorite hurricane clip of all time-- from the eyewall of Charley, when it was a strong Cat 4 in FL. Jim always manages a clean, steady shot-- no matter how violent the conditions. This is some of the most red-meat, Grade-A hurricane footage you'll see anywhere:

Link to comment
Share on other sites

I owe a lot of people here thanks and responses to specific questions and comments made over the last few days. I will do those tomorrow! :)

In the meantime, thanks so much to those of you who took an interest-- I was actually pleasantly surprised how many people read the whole account, because I know it was kind of long.

Link to comment
Share on other sites

Jim! So cool to see you post here! And thanks for sharing your perspective on that night. It's cool to have it in this thread-- makes it more complete.

For people who don't know Jim Edds... He is a top-notch weather videographer, and he's the one who shot my favorite hurricane clip of all time-- from the eyewall of Charley, when it was a strong Cat 4 in FL. This is some of the most red-meat, Grade-A hurricane footage you'll see anywhere:

Josh,

Do you have a link for the video from the eyewall of Charley?

Link to comment
Share on other sites

It's embedded in my post. Don't you see it? Here it is as a link:

Well, call me stupid. :arrowhead: I did not realize that video was of Hurricane Charley (working to many night shifts perhaps...and did not pay attention to the text at the top of the video). Thanks for posting the link though.

Link to comment
Share on other sites

This is the full account, for folks who have the time and like all the details. It's way more detailed than most of you want or need. Most of you should just skip to The Peak and Meteorological Discussion. :)

Congrats to you and Jim, sounds like it was a great chase.

Nice write-up too.

Link to comment
Share on other sites

First and foremost, thank goodness that you and Jim are OK!!!

After that, WOW!!! Just read your entire report. What an adventure, though perilous at times. I'm just very happy you didn't get hurt. Sounds like you ran into many nice Mexican folk, too. Simply amazing how that road crew came pretty much out of nowhere.

I totally agree that NHC would be very happy to get your report and video. As Ginxy said, I would LOVE to see that tree video.

Gotta run...meeting day today!!

--Turtle (from NWA meeting in Birmingham)

Link to comment
Share on other sites

Those Charley vids are why I am semi-anti-IMBY. IMBY does not produce the quality videos of highly populated Florida, with many trees, good road networks, and lots of civilization.

Not to mention IMBY is a once every other decade occurence. 2004 will always be my favorite adventure season.

I eagerly await the i-Cyclone presentation on Jova. And the best of i-Cyclone DVD and souvenir t-shirt, XXXLT.

I'm also curious to see if NHC post-season re-analysis maybe takes this to a SS 3 based on Josh's pressure and damage videos/footage.

Link to comment
Share on other sites

Awesome bro, so happy for you. Glad you are OK, congrats!!!

Thanks, Steve. We were able to get into that small radius of hurricane winds after all! ;)

That's awesome. I guess that last minute ramp up really helped out. Defintely better to have a slight strengthening cane at that pressure move ashore than something that is weakening at the same pressure.

Oh, totally! As time goes on, more and more I realize the gargantuan difference between strengthening and weakening ‘canes. The differences are enormous. Without knowing anything-- because we had no connection with the outside world in the final hours-- we could still tell that Jova was strengthening at landfall, because you could just feel that convective energy on the ground: the greatest bursts of wind coincided with very heavy rain. You don’t see that in crappy, falling-apart cyclone like Irene.

Thanks, man.

Wow Josh that sounds amazing, glad to see you are ok, get some rest and cant wait for the full report and video :thumbsup:

Thanks for reading it. :)

:thumbsup::wub:

:)

Glad you got a nice and brutal pounding. thumbsupsmileyanim.gif

Yeah, it felt pretty good-- really brought out my inner masochist. Thanks, Scott.

Congrats, Josh! Can't wait to see the video. weight_lift.gif

:wub:

Congrats Josh! How exciting! I am jealous.

Awww, thanks, Jaine.

Glad to know are safe and sound (or at least fairly sound).

When do you anticipate in getting back to the states?

Thank you. I didn’t actually rush back. I caught some much-needed R&R in Puerto Vallarta before heading home. It was just what the doctor ordered.

Congrats my friend, as well as major kudos to Scott, Jorge and Adam for working so hard to get Josh in the best possible location for a sucessful intercept. So much goes on behind the scenes to make these chase chances so

sucessfull. Josh even took time to check on me while I was in the hospital upon his arrival in Mexico and see how I was doing. Say what you want about the so called 'tropiclique', but we care about each other and are bound together by our love of all things tropics. I am proud to call all these guys and gals my friends.

Totally. It really is a team effort. Adam, Jorge, and especially Scott play such a critical role in these expeditions-- whether they’re physically present with me or not.

Reminds me in presentation of Juan 2003 making landfall at Halifax NS (recorded as a strong cat-2) ... also gave a very concentrated band of 120 kt gusts in the northeast quad of the eyewall. Given the 10 deg warmer seas for Jova's final approach, perhaps you were in fact in a major with this, could have been at cat-3 when it landed. Anyway, perfectly executed plan. Looking forward to videos or pix.

Interesting comparison! I would think Jova--, being deep in the tropics-- and Juan-- being up in the Canadian Maritimes--, would be difficult to compare structurally. Did Nova Scotia have 120-kt gusts in Juan? I heard no such reports of winds that high!

Anyhoo, thanks so much for taking an interest in the chase.

awesome Josh, and MAN do you ever deserve a daylight raid.

Ugh, tell me about it, dude! :lol: These nighttime chases are wearing on me-- although I can’t complain too much, because Irene was a half-and-half and Karl was in the day.

Woohoo! Told ya that EZ was going to be in the E eyewall with Careyes being in the eye ;)

I'm still kicking myself for not living up the adventure... .... what can I do? change religion, sexual preferences, divorce and have a big fat check account? bike.gif Oh, and cut off the sleeves of my shirts?

Evil Jorge. :D

Link to comment
Share on other sites

Video or it didn't happen ;).

:D As I mentioned, I had the camera running almost the entire time. There were challenges, of course-- the main one being that it was in the middle of the night. But we made do with the car headlights, and I was able to capture the action within a narrow range of vision. I hope to post a teaser the within two weeks.

Congrats Josh! :thumbsup:

Thank you. :)

congrats Josh!! Glad to hear you had an awesome time and are alright!!! I hope someday i will be able to get into a real hurricane... thumbsupsmileyanim.gif

There’s nothing quite like a good hurricane. Thank you very much for your well-wishes. It is nice to be home after such craziness.

Josh,

Congrats on the successful and exciting chase! Now on to the next one, wherever/whenever it may be.

Thanks, Larry. It looks like the next one is going to be next year! But I’m almost OK with that-- I feel almost satiated now.

Like I posted previously, I figured that the 'cane coming ashore would be quite intresting. Was a bit surprised that Josh was not expecting much though I do see his point, as things seemed to be going downhill for a while. I am probably among the few who actually like night 'cane video, so I am expecting some cool footage. Nice chase Josh!

Well, in that case, you’re probably gonna get off pretty good on this footage. :lmao:

And, yes, you ended up being right-- it was good when it came ashore. I should have listened to you all along. ;) Thanks for keeping the faith.

So what's up with this Man ~vs~ Wild, mechete swinging adventure I caught wind of today?

It was a learning experience, let’s just say. I’ve never seen such skilled handling of machetes in my entire life. It’s like everyone there is a pro.

We all know Josh secretly climbs up cliffs without ropes to get an unobstructed shot.

Well, maybe not that extreme-- but I do what I can for a good shot!

Excellent report, Josh!

That minimum pressure reading gives you an idea of just how ridiculous that Octobomb last year was for an extratropical cyclone.

Thank you so much.

Keep in mind, my 985.2 mb was ~8 n mi from the center of the eye. Most certainly the pressure in the eye was at least 10 mb lower-- maybe much more. Also, it’s hard to compare tropical cyclones-- especially small ones-- with extratropical ones, because the scales are completely different. The gradient of a tropical cyclone is typically much, much steeper.

This aside, thanks for your encouragement along the way. You were in this thread from the beginning. :)

Very interesting - thanks for the detailed report! I remember driving down the main highway in Baja weeks after a tropical storm in the 90s and the road was barely passable at times. Honestly, I'm surprised you weren't stuck there for days.

Oh, totally! I drove up and down the Baja Peninsula before and after Hurricane Jimena in 2009, and I had similar experiences. The highway along the coast of Jalisco is a much better road. Even so, there were major problems from downed trees and mudslides.

Nothing better for me awake with an atrocious cold than to get lost for several minutes--almost caught vicariously a bit into an adventure story-- in such a well-written analysis. Kudos to you ex-pat Long Islander!

:wub:

I’m so glad the account helped brighten a cruddy day. I was worried it was too long-- but it seems like a lot of folks actually read it!

P.S. I didn’t know you were a fellow Long Islander. :thumbsup:

Link to comment
Share on other sites

Awesome update Josh... Always enjoy reading your accounts! It's also got to feel nice you are helping out with the data void by providing a pressure reading near the center of the storm. You and Jim sound like an excellent team, both during and after the storm!

Thanks, Phil! Yeah, I’m hoping the pressure data and other obs can help the NHC figure out exactly what happened in the post-season analysis. I’m slightly bummed I didn’t get a pressure reading from the eye-- because I’m wondering if it was lower than the operationally assessed value of 973 mb-- but it was worth it to be in the right eyewall.

P.S. Sorry I snapped at you for talking about shear. I was a little on edge in those final hours. :D

Josh, that's awesome. Congrats on getting into the meat of the storm. Very much enjoyed the report at 5:45am on a Sunday morning.

:)

Thanks, man! I’m glad it provided some morning entertainment.

Compelling account, Josh.

Something to think about: a strengthening storm hitting a less-industrialized area

and less mass-media/less observational surveillance yet almost no deaths; perhaps 4 total. Maybe

those locals down there rely on common sense?

Thanks, Richard!

Great read and recap first thing in the morning, Josh! Look forward to seeing the video!

Thanks for reading it! :) I’m hoping to have the video live within the next two weeks. I’m eager to get it up!

Great recap, Josh! :thumbsup:

:wub: Thanks so much for helping Adam draw the cyclone track, so he could measure my distance from the center. Your map skillz are true hawtness.

Simply fascinating. I must of missed where you met up with Jim Edds as I thought you were solo on this one!

Yeah, we didn’t plan it-- I went out there planning to chase alone, and it just kind of happened. I’m glad it did-- it was the kind of chase that was best done with a partner. And Jim was awesome company. Glad you liked the report.

Awesome! glad everything worked out! love the part about clearing the highway! good morning read!

Thanks, Diane! I was actually going to chop that part out because it was so long, but at the last second I decided to leave it. Glad you liked it.

Probably the most exciting chase report I've read so far.

Google Streetview of the hideout http://maps.google.c...81,,0,4.74&z=19

:thumbsup:

Dude, that is the exact place! I didn’t even think to do that. Thanks for posting this link.

P.S. I’m so psyched you think it’s the best yet. Hopefully the video meets expectations. Yikes. :)

I'm guessing that is has to do with topography. Specifically, I imagine the winds at first were responding to the strong pressure gradient and blowing almost perpendicular to the isobars (this often happens in and near the foothills of mountains and exit areas of canyons--winds blow down-gradient instead of parallel to isobars). But once the core of the cyclone got close enough, the small area near it acted more like a traditional cyclone unless you were literally right at the canyon/valley exits, which you weren't.

Very interesting. That makes sense. It was so weird-- there needs to be some explanation for it. Thanks, Mallowberry.

Excellent report Josh, that's one heckuva chase. You're one of the few that can track down a cyclone like this in the middle of nowhere.

:wub:

Thanks, turtle. That’s one of the nicest things anyone has ever said to me.

Another potential topographical effect is hydraulic jumps, depending on the orientation of the hills and wind. I think even small hills can lead to that in such high speed flow. That could explain some of the violent gustiness.

And I will say, the winds definitely had a gusty quality. They were not totally steady-- the max winds came in big bursts, or “chains” of bursts. I’ve been reviewing the footage, and one of these chains lasted well over a minute--, but most others were a bit shorter.

Link to comment
Share on other sites

Josh,

Congrats on the successful chase, and thanks for the incredibly compelling and detailed report.

Aw, thanks, Scott-- I’m glad you were able to squeeze out the time to read it. I know your weekends are filled with family stuff.

What an exciting event! Thanks for the excellent report.

You’re very welcome-- thank you. :)

I read it all.. What an exciting adventure Josh! Congrats!

Awesome. I’m actually surprised how many people read the whole thing! Thank you. :)

As you are well aware, there is not much in the way of documentation of EPAC hurricanes when they make landfall. Although you didn't get any wind data, your report is still important and I'm sure that NHC would be happy to have it.

Steve

Totally agreed, Steve-- and I did reach out to Jack Beven with the data. He was grateful for it, mentioning that my obs are the only ones they have from the landfall region--, thus illustrating your point. I find it a bit frustrating how these cool cyclones come ashore on this saide with no radar, no surface obs, nothing. It’s a shame-- and I’m glad to make even a small dent in the problem.

That might be your most exciting recap ever.

Awesome-- I’m glad you felt that way, because it definitely felt like one of the more exciting ones.

Congrats to you and Jim, sounds like it was a great chase.

Nice write-up too.

Thanks for reading it!

First and foremost, thank goodness that you and Jim are OK!!!

After that, WOW!!! Just read your entire report. What an adventure, though perilous at times. I'm just very happy you didn't get hurt. Sounds like you ran into many nice Mexican folk, too. Simply amazing how that road crew came pretty much out of nowhere.

I totally agree that NHC would be very happy to get your report and video. As Ginxy said, I would LOVE to see that tree video.

Gotta run...meeting day today!!

--Turtle (from NWA meeting in Birmingham)

Thanks, Eleanor! I’m also glad we didn’t get hurt! :D

I went through the video and I caught the tree blowing down-- although what happens after that is less clear in all the confusion.

And, yes, the people were amazing-- they were all so nice and so helpful. The Mexicans are very hospitable people.

Those Charley vids are why I am semi-anti-IMBY. IMBY does not produce the quality videos of highly populated Florida, with many trees, good road networks, and lots of civilization.

Not to mention IMBY is a once every other decade occurence. 2004 will always be my favorite adventure season.

I eagerly await the i-Cyclone presentation on Jova. And the best of i-Cyclone DVD and souvenir t-shirt, XXXLT.

I'm also curious to see if NHC post-season re-analysis maybe takes this to a SS 3 based on Josh's pressure and damage videos/footage.

Thanks, Ed. I’m hope the video doesn’t disappoint! But keep in mind, it was at night, with limited light!

I would love if they upgraded Jova to a Cat 3, but I feel they would need a lot more hard evidence beyond what I’ve presented. Neither my pics nor mine and Jim’s wind estimates substantiate Cat 3. Perhaps they could analyze the video footage. :sun:

Great chase recap Josh! Looking forward to the video :)

Thanks, man. :)

Thanks for putting yourself in harms way for us again Josh! Looking forward to the next time!

I do it all for you. B)

Thanks, Sean.

What an AWESOME accounting!!!!!!!! Thank you Jim and JOSH for sharing!!!! Glad you are both safe!

So glad you liked it-- thank you.

Link to comment
Share on other sites

Continuing the Jova discussion from the N Atlantic thread...

What did you think of Jova's shock ending-- the sudden bombing out right before landfall? Were you surprised? :sun:

Regarding Jova, I'm glad you got a great chase out of it! :) I'm not sold though that it bombed out before landfall. It may have intensified somewhat before landfall, as suggested by the slightly improved satellite appearance and improving microwave structure. However, as intense as the conditions were at your location, I don't think it's necessarily evidence of Jova's max intensity given the i) enhanced elevation, ii) possible local topographic effects, and iii) getting lucky and being at THE location of max winds at landfall. If I had to take a stab at it, I would say it's highly doubtful that Jova reattained major hurricane status at landfall, which is really a testament to how impressive true Cat 2 conditions really are.

Interesting take on Jova-- thanks for sharing it. I mostly agree, but wanted to make a few comments.

Firstly... I don't think anyone said it was a Cat 3. While I think it was stronger than 85 kt*, I also feel the NHC would need some pretty compelling evidence to bump it to 100 kt in post-season analysis-- evidence that probably doesn't exist due to the lack of data. But since you brought it up, I'm wondering if you think it might have been a Cat 3. Do you?

Perhaps I might have been overstating to say it was "bombing out". But I wonder if you're understating the intensification in those final hours. Yeah, the IR images don't look amazing, but microcanes (a la Charley, Humberto, etc.) often have deceptively lame IR presentations because IR imagery just can't capture detail on that scale. The composite and 89H images (below) are much more revealing-- and don't you think they look radically better than the complete crap from 12-24 hr earlier? I mean, there's a closed eyewall with a distinct eye-- which was also showing up in IR (bottom pic). I feel the structural changes in those final hours were significant.

This aside... Jim and I were actually the first to point out that elevation might have played some role in what we saw. But I think it's important not to overstate this factor. We were at 73 ft. We were not at Blue Hill Observatory (635 ft) or Mount Washington. :D Also keep in mind that while we might have had some minor elevation-driven enhancement, we were also ~2 n mi inland, meaning we were not getting marine-exposure wind.

I'm not arguing Jova was a Cat 3-- I'm not qualified to say that. I'm just saying it was a potent cyclone and perhaps stronger than operationally assessed. I will say it was way worse than any other Cat 2 I've been in-- and it actually felt noticeably more severe than Karl 2010, a presumed 100-kt Cat 3. (In that one, I was in the left eyewall.)

* Note: When I say I think Jova was stronger than 85 kt, I'm not saying I think we had 10-m/1-min winds of over 85 kt at our location. Being ~2 n mi inland and in a semi-urban environment, we wouldn't get the marine-exposure/open-coast winds reflected in the official intensity. I'm making allowances for the fact that we were inland and not in an exposed location.

post-19-0-48192900-1319190258.jpg post-19-0-54920200-1319190269.jpg

post-19-0-78966000-1319190282.jpg

Link to comment
Share on other sites

Great writeup Josh - congrats on a great chase! Also good to hear that the area survived without too much damage. Such a pretty area and relatively untouristy once you get out of PV. Any idea of how the Barra/Melaque and the Costa Careyes areas fared?

Link to comment
Share on other sites

Great writeup Josh - congrats on a great chase! Also good to hear that the area survived without too much damage. Such a pretty area and relatively untouristy once you get out of PV. Any idea of how the Barra/Melaque and the Costa Careyes areas fared?

Thanks very much.

Melaque/Barra de Navidad are fine, because the cyclone was small and they were well outside of the core. Careyes was near the point of landfall so had a direct impact, which seemed approximately like what we had in Emiliano Zapata. To be clear, the impacted area had plenty of damage-- it was quite a mess-- but it wasn't what I would call "devastation".

Link to comment
Share on other sites

Continuing the Jova discussion from the N Atlantic thread...

Interesting take on Jova-- thanks for sharing it. I mostly agree, but wanted to make a few comments.

Firstly... I don't think anyone said it was a Cat 3. While I think it was stronger than 85 kt*, I also feel the NHC would need some pretty compelling evidence to bump it to 100 kt in post-season analysis-- evidence that probably doesn't exist due to the lack of data. But since you brought it up, I'm wondering if you think it might have been a Cat 3. Do you?

Perhaps I might have been overstating to say it was "bombing out". But I wonder if you're understating the intensification in those final hours. Yeah, the IR images don't look amazing, but microcanes (a la Charley, Humberto, etc.) often have deceptively lame IR presentations because IR imagery just can't capture detail on that scale. The composite and 89H images (below) are much more revealing-- and don't you think they look radically better than the complete crap from 12-24 hr earlier? I mean, there's a closed eyewall with a distinct eye-- which was also showing up in IR (bottom pic). I feel the structural changes in those final hours were significant.

This aside... Jim and I were actually the first to point out that elevation might have played some role in what we saw. But I think it's important not to overstate this factor. We were at 73 ft. We were not at Blue Hill Observatory (635 ft) or Mount Washington. :D Also keep in mind that while we might have had some minor elevation-driven enhancement, we were also ~2 n mi inland, meaning we were not getting marine-exposure wind.

I'm not arguing Jova was a Cat 3-- I'm not qualified to say that. I'm just saying it was a potent cyclone and perhaps stronger than operationally assessed. I will say it was way worse than any other Cat 2 I've been in-- and it actually felt noticeably more severe than Karl 2010, a presumed 100-kt Cat 3. (In that one, I was in the left eyewall.)

* Note: When I say I think Jova was stronger than 85 kt, I'm not saying I think we had 10-m/1-min winds of over 85 kt at our location. Being ~2 n mi inland and in a semi-urban environment, we wouldn't get the marine-exposure/open-coast winds reflected in the official intensity. I'm making allowances for the fact that we were inland and not in an exposed location.

I really, really doubt it was a Cat 3.

With that said, it was getting better organized in the few hours before landfall. The microwave image you posted at 0358z is impressive and appears to show a closed eyewall. The reason why I don't think it was able to intensify *that* much was because the previous few microwave passes (0126, 0209, and 0234z below) all showed an open eyewall. The change in the last couple hours was structurally significant, certainly, but that isn't really a whole lot of time for a response in the central pressure and then the winds. It may have fallen a few mbs in that couple hour time span, whereas before then it was probably steady state or slowly falling. The intensified convection may have mixed the winds down more effectively too, but I still think it was probably on the order of 85-90 kt at landfall. We'll never really know.

The elevation thing isn't a huge issue...that amount of elevation probably increases the winds on the order of 3-5%. How does the distance inland and overall exposure of your location compare with past chases?

20111012.0234.f18.x.colorpct_91h_91v_1deg.10EJOVA.85kts-973mb-186N-1052W.64pc.jpg

Link to comment
Share on other sites

Here's the barogram from Cory's Kestrel (which I took on this chase), showing the the air pressure drop and recovery as Jova's center passed 8 n mi to our W. (Thanks to Cory for sending me the Kestrel Communicator so I could graph it.)

The graph only covers 11:12 pm CDT 11 Oct to 1:37 am CDT 12 Oct, as that was the time during which we were at a fixed location. As I mentioned previously, the Kestrel was calibrated for an elevation of 73 ft, which is what the car's GPS system indicated.

A couple of things:

* Lowest Pressure & Time. The lowest pressure (985.2 mb) occurred at 12:33 am CDT, suggesting the center reached its point of closest approach at that time. This corresponds very well with the NHC advisory positions.

* Peak Conditions in SE Eyewall. Based on a preliminary review of the video footage, it seems the highest winds (and heaviest rain) occurred ~12:45 am to 1:00 am CDT-- a little after the center passed by. This suggests the severest conditions were in the SE eyewall-- a suspicion which is well corroborated by this remark from the NHC's post-landfall Discussion:

BEFORE THE CENTER OF JOVA MOVED INLAND...AN EYE WAS BRIEFLY APPARENT IN GEOSTATIONARY IMAGERY...AND A SERIES OF MICROWAVE IMAGES BETWEEN 0000 AND 0300 UTC SHOWED A WELL-DEFINED MID-LEVEL EYE. THEREFORE IT IS ESTIMATED THAT JOVA MAINTAINED AN INTENSITY OF 85 KT UNTIL LANDFALL AROUND 0500 UTC. SINCE LANDFALL THE EYE HAS DISAPPEARED IN GEOSTATIONARY IMAGERY AND THE CONVECTIVE PATTERN HAS BECOME ELONGATED...
WITH MOST OF THE COLD TOPS NOW LOCATED SOUTH AND EAST OF THE CENTER.

post-19-0-38988500-1319497845.png

Link to comment
Share on other sites

The more rapid rise in pressure after the center passed would also seem to support stronger winds. Don't know if there was a tighter gradient on the back, (the low pressure was distorted, not circular) or if there is an isoallobaric component (and whether it is cause or affect), but just intuitively, I'd expect stronger winds where the time rate of change of pressure was higher.

JovaBarogramPNG2.PNG

Link to comment
Share on other sites

:thumbsup: Love seeing those graphs!

Me, too. You know you're a meganerd when you get off on air-pressure graphs. :wub:

The more rapid rise in pressure after the center passed would also seem to support stronger winds. Don't know if there was a tighter gradient on the back, (the low pressure was distorted, not circular) or if there is an isoallobaric component (and whether it is cause or affect), but just intuitively, I'd expect stronger winds where the time rate of change of pressure was higher.

Good observation. I noticed that, too-- the apparently tighter gradient in the SE eyewall (versus the NE eyewall). I was in the editing room today reviewing the footage, and the heaviest conditions occurred from around ~12:35 am to ~1:10 am CDT, with the biggest, most violent gusts happening between ~12:45 and ~1 am.

Link to comment
Share on other sites

A couple of things:

* Analysis. Since this chase, I've gotten deep into some analysis Re: the cyclone's size and intensity at landfall. The reason is because 1) it was surprisingly severe on the ground and 2) there's just so little data. Gathering what few scraps of evidence I've been able to piece together (including my own air-pressure data), having some eMail discussions with a PhD expert in RMWs, applying Atlantic reanalysis methodologies, and enlisting Adam's help with some of the gnarlier math, I've done some calculations that suggest Jova had winds of 95 or 100 kt at landfall-- a bit stronger than the operationally assessed 85 kt. I'm going to submit my reasoning and calculations to Chris Landsea to get his take on it-- to see if he thinks my analysis is valid. If he does, I'll post it here-- I just want to get some validation from an authority first.

* Video Teaser. My video teaser of Jova's landfall will be go live Friday. B) Woo hoo!

More soon!

Link to comment
Share on other sites

A couple of things:

* Analysis. Since this chase, I've gotten deep into some analysis Re: the cyclone's size and intensity at landfall. The reason is because 1) it was surprisingly severe on the ground and 2) there's just so little data. Gathering what few scraps of evidence I've been able to piece together (including my own air-pressure data), having some eMail discussions with a PhD expert in RMWs, applying Atlantic reanalysis methodologies, and enlisting Adam's help with some of the gnarlier math, I've done some calculations that suggest Jova had winds of 95 or 100 kt at landfall-- a bit stronger than the operationally assessed 85 kt. I'm going to submit my reasoning and calculations to Chris Landsea to get his take on it-- to see if he thinks my analysis is valid. If he does, I'll post it here-- I just want to get some validation from an authority first.

* Video Teaser. My video teaser of Jova's landfall will be go live Friday. B) Woo hoo!

More soon!

Teaser- does that mean a full length DVD and 3XLT souvenir t-shirts are coming?

BTW, if you're obs get used in post-season reanalysis, especially if they go the full 100 knot route, that would make you an official rock star.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...