Powerful Category 3 Hurricane Jova nears landfall in Mexico

By: Dr. Jeff Masters , 1:42 PM GMT on October 11, 2011

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Rain bands from powerful Category 3 Hurricane Jova are already deluging the southwest coast of Mexico as the storm heads towards landfall late this afternoon between Manzanillo and Puerto Vallarta. Recent satellite loops show the hurricane has weakened since yesterday afternoon, with the eye no longer visible and the cloud pattern no longer as symmetric. Moderate wind shear of 15 - 20 knots due to strong upper-level winds out of the southeast managed to inject some dry air into the core of Jova that disrupted the storm's eyewall, and it is unlikely the hurricane will be able to intensify beyond its current 115 mph strength before landfall. It is more likely that Jova will weaken as it approaches land, due to the storm's small size, which makes is vulnerable to disruption when the outer portion of the circulation hits the mountains along the Mexican coast. If Jova maintains its Category 3 strength until landfall, it will rank as one of the ten most intense Pacific hurricanes to hit Mexico since record keeping began in 1949, according to a comprehensive list of Eastern Pacific hurricane landfalls at Wikipedia. However, I expect Jova's interaction with the high mountains of Mexico will knock it down to a Category 2 storm with 100 - 105 mph winds by landfall. Hurricane-force winds extend outwards only 15 miles from the center of Jova, so a relatively small stretch of moderately to lightly-populated stretch of coast will see Jova's high winds and dangerous storm surge. A much larger swath of Mexico will see very heavy rains of 6 - 12 inches, and these rains are the primary threat from the hurricane.

The shape of the coast near Puerto Vallarta makes it difficult for a high storm surge to affect that city. Jova is passing far enough to the east of Puerto Vallarta that the winds in the Bay should be capable of elevating a surge to a height of just 1 - 2 feet above normal water levels, with perhaps a slight chance of a surge as high as 3 feet affecting the city. However, there will be high battering waves on top of the storm surge, and these waves may cause damage to ocean front property. I was in Puerto Vallarta during Hurricane Paine of 1986, and while we didn't see much of a storm surge, the coast experienced 10-foot waves that tore apart the sea wall protecting the swimming pool of the hotel I was staying at. The highest storm tide from Jova should occur near 9:55am CDT Wednesday morning, which is the time of high tide. Jova will be at its closest to Puerto Vallarta then, and is likely to be a strong tropical storm with 60 mph winds.


Figure 1. True-color MODIS image of Jova taken at 1:40 pm EDT October 10, 2011. At the time, Jova was a Category 3 hurricane with 125 mph winds. Image credit: NASA.


Figure 2. Rainfall forecast for Hurricane Jova from this morning's 2 am EDT run of the GFDL model. Image credit: Morris Bender, NOAA/GFDL.

Links to follow Jova
Wunderblogger Mike Theiss is in Barra de Navidad, just north-west of Manzanillo, and will be giving us live blogs and photos from the landfall of Jova, as his power and Internet connections permit.

Manzanillo weather

>Puerto Vallarta webcam

Tropical Depression Irwin also headed for Mexico
Once Jova has made landfall, Tropical Depression Irwin, farther to the west, may also be a concern. The computer forecast models show that late this week, Irwin will approach the same stretch of Mexican coast Jova is affecting. However, Irwin is a weak storm that is may not survive, due to high wind shear, and may end up not bringing significant rains to Mexico.

Quiet in the Atlantic
There are currently no threat areas in the Atlantic, now that Invest 93L has moved ashore over the Southeast U.S. Invest 93L did have tropical storm force winds, and will be re-analyzed in the off-season by NHC to see if it did indeed have enough organization to qualify as an unnamed subtropical storm.

The ECMWF and NOGAPS models continue to predict that a strong tropical disturbance capable of becoming a tropical depression could form in the Western Caribbean early next week. Some of the spin and moisture for this storm could potentially come from an area of disturbed weather in the Eastern Pacific, (Invest 99E), that is currently just offshore of the Mexico/Guatemala border. Invest 99E is expected to move inland over Central America over the next few days, bringing very heavy rains capable of causing flash flooding and mudslides to Southeast Mexico, Guatemala, and El Salvador.

Jeff Masters

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Quoting weatherh98:



looks like 3 ppl on tonight
And they all have each other on ignore.

Does anybody here know how a meadow evolves through stages until finally the tall trees , usually of one species, take over and smother out the other species? Well that has happened on this blog too. And as in the forest of old diseased trees, lightening must come and burn down the old growth and allow the sunshine to reach the ground again.

Yes it is quiet in the forest and on the blog tonight!
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Quoting wunderweatherman123:
hey do you know any avaliable radars where jova is making landfall? also its been since 2006 since the e pac has gotten 9 or more hurricanes :P

Not that I know of, no.
Member Since: July 6, 2010 Posts: 113 Comments: 32338
Hurricane Jova to slam Mexico overnight

Indeed this is a horrible situation for Mexico. Unfortunately, even once she weakens she will still be a huge threat in terms of rainfall.
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To my untrained eye Jova looked a little better this afternoon and now looks a little worse. It is hard to see the eye. Jova will probably maintain her strength until landfall.
Member Since: August 9, 2011 Posts: 26 Comments: 8630
Quoting TropicalAnalystwx13:
hey do you know any avaliable radars where jova is making landfall? also its been since 2006 since the e pac has gotten 9 or more hurricanes :P
Member Since: August 23, 2011 Posts: 0 Comments: 1725
Quoting TropicalAnalystwx13:



looks like 3 ppl on tonight
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Member Since: July 6, 2010 Posts: 113 Comments: 32338
Quoting wunderweatherman123:
jova jova maintaining cat 2 status... why cant she just fall apart?? :(


because shes a loon duuuh
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jova jova maintaining cat 2 status... why cant she just fall apart?? :(
Member Since: August 23, 2011 Posts: 0 Comments: 1725
Quoting pottery:

No Prob.
I just came in to read all of today's comments that I had missed.

Some very good stuff there.

I'm out too >>>>>>

Ok, bye >>>>>>>>>>>>>
Member Since: July 6, 2010 Posts: 113 Comments: 32338
Quoting weatherh98:


about nobody is here

No Prob.
I just came in to read all of today's comments that I had missed.

Some very good stuff there.

I'm out too >>>>>>
Member Since: October 24, 2005 Posts: 0 Comments: 24452
TS Banyan continues to soak the Middle Philippines, churning into open sea and maintaining strength precipitation-wise. It will likely become the third tropical cyclone to hit Hainan Province of Southern China in as many weeks.



Meanwhile, the remnants of 93L trudge through the Appalachians, dragging behind a convective blob that extends as far south as Hispanola. The system brought flooding rains and winds to Florida, and reminds me of the un-named Carolinas September storm a few years back. The system is still getting moisture and will bring rain into Southern Ontario tomorrow.
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Quoting pottery:
Today's Discussion, Argument, Diagnosis, and Debate from just about everyone on 93L was all highly Informative and Educational.

Thank you all who participated.
This is a Great Blog.

Carry on>>>>>>>>>


about nobody is here
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Today's Discussion, Argument, Diagnosis, and Debate from just about everyone on 93L was all highly Informative and Educational.

Thank you all who participated.
This is a Great Blog.

Carry on>>>>>>>>>
Member Since: October 24, 2005 Posts: 0 Comments: 24452
is the blog dead tonight?????????
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252. Skyepony (Mod)
Tom~ I have no doubt the system was closed. I have a PWS in my back yard. It closed as it hit land or came on land in a very short amount of time. 950mb is not surface. I live there & know what 10-20 miles looks like. It's ~60 miles from NWS to KSC. It's near 10 miles from NWS to the Beach as the crow flies.. It was interesting watching it on wundermap. That area is littered with Personal Weather Stations. Please note the time at MLB airport that the true west wind hit.. this is when the surface low would have been due north of Melbourne on land..22:53. Now note the time at the end of the loop when radar has center still offshore 2:26..3 1/2 hrs later. By the end of the loop MLB is already havin South winds, showing the low was even farther inland. It was horribly stacked. Being that close to the radar makes it even more horribly stacked. Please realize Vero winds are in eastern time.. At around 7pm when the surface low moved N of them on land is the first we see on the radar that 93L was getting rapped up..(look farther back in time then what you posted) I'm not sure if the surface low wasn't on land from the get go which is another mark for MCV...

& wasn't that broad surface low late that night in the GOM on Oceansat from the ULL above it? Are you saying that ULL was supporting a broad surface low under it & 93L across the state at the same time?

I don't know if this will get upgraded postseason, it may or may not. There is a lot of devil in the details that need looked at cause it was very close, fast & evolved in a somewhat unusual way.. Had it had a few more hours over water or atleast not had all the cold west winds here on land while it was offshore on radar, I think it would have been named that night. I have no problems with how NWS & NHC handled it though. I lived through it & was warned accordingly.

Couple of big trees in the hood down, 2 dead oaks fell here, 3 truck loads of debris off my place. That big sign on Hibiscus where you turn to the mall is down. Saw some crooked stop signs on Babcock.

Cosmic~ Thanks

Tampa~ Taking the time to look at the details in the definitions:) We need more of that here..

IceCoast~ Thanks for the great example of a MCV. I probably refer to them as landcanes way more than I should.

Levi~ Thanks for sharing the NHC response.

I'm over 93L..I see the Cuba/Haiti blob drifted a little more west at the surface than I expected today..got all hung up on the east side of Cuba while shear came up to 20kts & blew it's mid level vort to the North..
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Complete Update

TS BUSTED FORECAST ALIBI





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Quoting wunderweatherman123:
so the 11pm still will be 100mph? figured a cat 2 at landfall... those are pretty rare for mexico and dangerous

Well, the NHC does differ from the ATCF file every once in a while, but there is about a 9/10 chance of it being the same intensity at 11PM.
Member Since: July 6, 2010 Posts: 113 Comments: 32338
What a hopeless group with their " warning products and suites". What becomes apparent is that there is a lot of duplication between the NHC and NWS, with an abundance of "branch managers" all trying to protect their turf.

Now they will have this "summit" in order to give the appearance they are performing a task of a natural security nature deciding what this stupid 93 was.

This is of no importance to the country in these hard times and should be wrapped up NOW.
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I am on Providenciales, the triangle shaped island in the white area North of Hispaniola.

We have had light winds all day, just now the breeze has sprung up from the South, 15 to 18 mph, I will watch the Barometer overnight... when I tapped it now, it is steady.
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212. There you have it folks, we can stop bashing the NHC now, they'll upgrade it post-season.

So whatever our total is come Jan 1st, you can add +1 to that total.
Member Since: July 8, 2005 Posts: 259 Comments: 24248
Quoting TropicalAnalystwx13:
Jova has not changed;

EP, 10, 2011101200, , BEST, 0, 186N, 1052W, 85, 973, HU, 64, NEQ, 15, 15, 15, 15, 1006, 180, 10, 0, 0, E, 0, , 0, 0, JOVA, D,
so the 11pm still will be 100mph? figured a cat 2 at landfall... those are pretty rare for mexico and dangerous
Member Since: August 23, 2011 Posts: 0 Comments: 1725
Jova has not changed;

EP, 10, 2011101200, , BEST, 0, 186N, 1052W, 85, 973, HU, 64, NEQ, 15, 15, 15, 15, 1006, 180, 10, 0, 0, E, 0, , 0, 0, JOVA, D,
Member Since: July 6, 2010 Posts: 113 Comments: 32338


Member Since: July 6, 2010 Posts: 113 Comments: 32338
Winds still 35 mph; Pressure still 1006 mbar.

EP, 99, 2011101200, , BEST, 0, 137N, 941W, 30, 1006, LO, 34, NEQ, 0, 0, 0, 0, 1009, 200, 60, 0, 0, E, 0, , 0, 0, INVEST, S,
Member Since: July 6, 2010 Posts: 113 Comments: 32338
Quoting KipHansen:
Is Jova going to bring rain to drought-stricken Western Texas?


I don't think so. A cold front is forecast for the high plains/west Texas. Some rain from Jova possible in deep south Texas. (Brownsville, Laredo etc)
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Jova firing off some very cold cloud tops over the center as landfall approaches.



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240. wpb
mexico radar not on the website
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Quoting Levi32:
I feel it is appropriate to share this response which I received from James Franklin, one of the NHC forecasters, after I inquired on the issue of 93L and why it was not named on the spot. I feel that it is ok for me to share this since they have developed this response for all questions related to 93L's treatment by the NHC.

Dear Levi,

We've gotten a few inquiries on this, and prepared the following by way of response:

During the weekend of 8-9 October, the state of Florida was affected by a large and complex weather system, one that was not designated as a tropical or subtropical cyclone operationally by the National Hurricane Center (NHC). Watches, warnings, and forecasts for this system were provided by local National Weather Service (NWS) Weather Forecast Offices (WFOs), most notably WFO Melbourne and WFO Jacksonville, while marine analyses and forecasts were provided by NHC's Tropical Analysis and Forecast Branch (TAFB).

There have been a number of inquiries as to whether this system was a tropical or subtropical cyclone. It is not uncommon for NHC to reclassify a system after an event based on a post-storm analysis, adding it to the historical record as an unnamed tropical or subtropical cyclone. A post-storm analysis is planned for this system to see whether it met either of the following definitions:

Tropical cyclone - A warm-core non-frontal synoptic-scale cyclone, originating over tropical or subtropical waters, with organized deep convection and a closed surface wind circulation about a well-defined center. Once formed, a tropical cyclone is maintained by the extraction of heat energy from the ocean at high temperature and heat export at the low temperatures of the upper troposphere.

Subtropical cyclone - A non-frontal low pressure system that has characteristics of both tropical and extratropical cyclones. This system is typically an upper-level cold low with circulation extending to the surface layer and maximum sustained winds generally occurring at a radius of about 100 miles or more from the center. In comparison to tropical cyclones, such systems have a relatively broad zone of maximum winds that is located farther from the center, and typically have a less symmetric wind field and distribution of convection.

Nature is capable of generating a wide spectrum of low-pressure systems that don't always neatly fit into the classification systems developed by meteorologists. The weather system that affected Florida this weekend contained characteristics of both tropical and non-tropical weather systems, making its classification difficult. Because of the system's non-tropical origins, the initial warning products on the system originated from NWS WFOs, and in fact the potential impacts of this event had been advertised in WFO products up to a week in advance.

During the afternoon of 9 October, a broad area of low pressure developed off the Florida east coast. Even before this time, gale-force winds were occurring over a large area offshore, and reached the coast by the late afternoon. In some respects the system resembled a subtropical cyclone at this time. During the evening, however, the low became better defined and strengthened near the Florida coast, briefly accompanied by a very small core of strong winds more characteristic of a tropical cyclone. These winds affected the Cape Canaveral area. During the event, WFO Melbourne issued a High Wind Warning for several coastal counties and a Storm Warning for the coastal waters -both rare issuances.

The overriding consideration for NHC not to name this system during the late afternoon or evening hours was a desire to preserve the flow of watch/warning/hazard information that had been coming from the NWS WFOs. NHC coordinated warning options with the affected WFOs throughout the day Sunday. Because the hazardous weather conditions were already occurring by the time the cyclone and its circulation had become well defined, it was agreed that users would be best served by not abruptly changing the product/warning suite to tropical/subtropical issuances, with the ultimate status of the system to be determined from a post-storm analysis.

I hope this is helpful in explaining how this system was handled.

Regards,

James
--
James L. Franklin

Branch Chief, Hurricane Specialist Unit
NOAA/NWS/National Hurricane Center


Notice how he says that 93L exhibited both non-tropical and tropical characteristics. In other words, they acknowledge that it was at least partially warm-core, and likely deserves some sort of classification, but they decided to wait until after the fact in order to avoid disrupting the flow of warning products being given to the public through the local NWS WFOs. I can understand this line of reasoning, and obviously we don't know anything about how coordination between offices works and the dynamics of communicating with the public. I'm sure they were trying to keep the public's best interest in mind. I fully expect them to upgrade invest 93L to an unnamed subtropical or tropical storm after post-analysis.

Thank you Levi for sharing that...Looks like it will be upgraded in post-season.
Member Since: July 6, 2010 Posts: 113 Comments: 32338
Quoting TampaSpin:



NOT over yet as i was just in the GOM and its still plenty warm yet. Fingers crossed!
I say the same, but the shear has to let up somewhere for something to form, it's been kicking every storms butt this year. Still, only little pockets open for any kind of development.
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000
ABNT20 KNHC 112333
TWOAT

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 PM EDT TUE OCT 11 2011

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE NEXT 48 HOURS.

$$
FORECASTER CANGIALOSI






Why? WHYYYYYYY??
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Just want to throw in my 2 cents on 93L, I'm no expert by any means, but I think 93L was handled appropriately by the NHC, it was one those systems that you're damn if you do and damned if you don't, frankly to me it only looked like a STS after it was over land and they(NHC) did issued gale warnings as is appropriate for any hybrid/cold/warm core system, but just for arguments sake it can be said" a rose by any other name is still a rose" , just some roses smell a little better than others :)
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Is Jova going to bring rain to drought-stricken Western Texas?
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Quoting wunderweatherman123:
jova still 100mph. u guys think she will be this strong at landfall?


I think it will be. Maybe slightly weaker, but not by much, so it won't make much of a difference for Mexico.
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Seems like every year, at some point I post a copy of the NHC Mission statement... I will bold a part I think some people forget:


Mission
(Why We Exist)

To save lives, mitigate property loss, and improve economic

efficiency
by issuing the best watches, warnings,

forecasts and analyses of hazardous tropical

weather, and by increasing understanding of these hazards.

Vision
(What We Hope to Achieve)

To be America's calm, clear and trusted

voice in the eye of the storm,

and, with our partners, enable communities

to be safe from tropical weather threats.

================================

There have been scholarly papers written on the "cost per mile" to the economy caused by Hurricane warnings. I am confident that costs are incurred due to lost productivity etc. even from "Tropical storm warnings". In years past, the NHC suffered very strong criticism by both the Bahamas and the Florida Keys (two that I know of) for substantial economic damage done to their tourist based economies, after warnings were issued for systems which were "marginal".

It behooves the forecasters... since it IS a part of the official Mission Statement, to take economic and other factors into consideration when naming a system. Ivory Tower meteorologists may want an exact criteria to be followed in naming systems, however, in my opinion, the NHC MUST take other factors into consideration... and sort out any questionable definition details in later analysis.
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jova still 100mph. u guys think she will be this strong at landfall?
Member Since: August 23, 2011 Posts: 0 Comments: 1725
Quoting Hurricanes101:


Id like to know what robert88 and Frank have to say about the NHCs response. They basically justified all of us who felt this should have been classified

and it will be in post-season


Yeah, and they way they went about it did make sense. All of those warnings, watches, and advisories were already out.

To be honest, even though it wasn't named, people down there had the same amount of warning, the potential was talked about for days by private and public sectors alike, and the NWS offices did a great job covering the situation and doing what needed to be done.
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230. wjdow
If you believe the NHC, which I do, given the short amount of time that invest 93 might have become a named system, they elected not to name the system and thereby interrupt the local warning system that was already active. Some people on this blog hammered NHC for not making the correct technical call as soon as they might have, but in retrospect NHC appears to have made the best decision consistent with its mission of helping to protect lives and property. Do people agree? Thank you, Levi for your post.
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Good evening.
Quoting Levi32:
I feel it is appropriate to share this response which I received from James Franklin, one of the NHC forecasters, after I inquired on the issue of 93L and why it was not named on the spot. I feel that it is ok for me to share this since they have developed this response for all questions related to 93L's treatment by the NHC.

Dear Levi,................
Notice how he says that 93L exhibited both non-tropical and tropical characteristics. In other words, they acknowledge that it was at least partially warm-core, and likely deserves some sort of classification, but they decided to wait until after the fact in order to avoid disrupting the flow of warning products being given to the public through the local NWS WFOs. I can understand this line of reasoning, and obviously we don't know anything about how coordination between offices works and the dynamics of communicating with the public. I'm sure they were trying to keep the public's best interest in mind. I fully expect them to upgrade invest 93L to an unnamed subtropical or tropical storm after post-analysis.

Cool how they actually responded. I'm pretty darn sure that 93L will be upgraded in post-season analysis.
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Why does the NHC advisory say Jova is at 100 MPH and the Wunderground one say's 95 MPH? It's the same advisory.
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Quoting TomTaylor:
Very cool to see the NHC respond to the public like that, props to them.

Also looks like they also believe it was subtropical too, they just didn't upgrade it for the sake of not wasting warnings on a storm that would be overland in an hour. No surprise there.


Id like to know what robert88 and Frank have to say about the NHCs response. They basically justified all of us who felt this should have been classified

and it will be in post-season
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Quoting Levi32:
I feel it is appropriate to share this response which I received from James Franklin, one of the NHC forecasters, after I inquired on the issue of 93L and why it was not named on the spot. I feel that it is ok for me to share this since they have developed this response for all questions related to 93L's treatment by the NHC.

Dear Levi,

We've gotten a few inquiries on this, and prepared the following by way of response:

During the weekend of 8-9 October, the state of Florida was affected by a large and complex weather system, one that was not designated as a tropical or subtropical cyclone operationally by the National Hurricane Center (NHC). Watches, warnings, and forecasts for this system were provided by local National Weather Service (NWS) Weather Forecast Offices (WFOs), most notably WFO Melbourne and WFO Jacksonville, while marine analyses and forecasts were provided by NHC's Tropical Analysis and Forecast Branch (TAFB).

There have been a number of inquiries as to whether this system was a tropical or subtropical cyclone. It is not uncommon for NHC to reclassify a system after an event based on a post-storm analysis, adding it to the historical record as an unnamed tropical or subtropical cyclone. A post-storm analysis is planned for this system to see whether it met either of the following definitions:

Tropical cyclone - A warm-core non-frontal synoptic-scale cyclone, originating over tropical or subtropical waters, with organized deep convection and a closed surface wind circulation about a well-defined center. Once formed, a tropical cyclone is maintained by the extraction of heat energy from the ocean at high temperature and heat export at the low temperatures of the upper troposphere.

Subtropical cyclone - A non-frontal low pressure system that has characteristics of both tropical and extratropical cyclones. This system is typically an upper-level cold low with circulation extending to the surface layer and maximum sustained winds generally occurring at a radius of about 100 miles or more from the center. In comparison to tropical cyclones, such systems have a relatively broad zone of maximum winds that is located farther from the center, and typically have a less symmetric wind field and distribution of convection.

Nature is capable of generating a wide spectrum of low-pressure systems that don't always neatly fit into the classification systems developed by meteorologists. The weather system that affected Florida this weekend contained characteristics of both tropical and non-tropical weather systems, making its classification difficult. Because of the system's non-tropical origins, the initial warning products on the system originated from NWS WFOs, and in fact the potential impacts of this event had been advertised in WFO products up to a week in advance.

During the afternoon of 9 October, a broad area of low pressure developed off the Florida east coast. Even before this time, gale-force winds were occurring over a large area offshore, and reached the coast by the late afternoon. In some respects the system resembled a subtropical cyclone at this time. During the evening, however, the low became better defined and strengthened near the Florida coast, briefly accompanied by a very small core of strong winds more characteristic of a tropical cyclone. These winds affected the Cape Canaveral area. During the event, WFO Melbourne issued a High Wind Warning for several coastal counties and a Storm Warning for the coastal waters -both rare issuances.

The overriding consideration for NHC not to name this system during the late afternoon or evening hours was a desire to preserve the flow of watch/warning/hazard information that had been coming from the NWS WFOs. NHC coordinated warning options with the affected WFOs throughout the day Sunday. Because the hazardous weather conditions were already occurring by the time the cyclone and its circulation had become well defined, it was agreed that users would be best served by not abruptly changing the product/warning suite to tropical/subtropical issuances, with the ultimate status of the system to be determined from a post-storm analysis.

I hope this is helpful in explaining how this system was handled.

Regards,

James
--
James L. Franklin

Branch Chief, Hurricane Specialist Unit
NOAA/NWS/National Hurricane Center


Notice how he says that 93L exhibited both non-tropical and tropical characteristics. In other words, they acknowledge that it was at least partially warm-core, and likely deserves some sort of classification, but they decided to wait until after the fact in order to avoid disrupting the flow of warning products being given to the public through the local NWS WFOs. I can understand this line of reasoning, and obviously we don't know anything about how coordination between offices works and the dynamics of communicating with the public. I'm sure they were trying to keep the public's best interest in mind. I fully expect them to upgrade invest 93L to an unnamed subtropical or tropical storm after post-analysis.
Very cool to see the NHC respond to the public like that, props to them.

Also looks like they also believe it was subtropical too, they just didn't upgrade it for the sake of not wasting warnings on a storm that would be overland in an hour. No surprise there.
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Quoting Levi32:
I feel it is appropriate to share this response which I received from James Franklin, one of the NHC forecasters, after I inquired on the issue of 93L and why it was not named on the spot. I feel that it is ok for me to share this since they have developed this response for all questions related to 93L's treatment by the NHC.

Dear Levi,

We've gotten a few inquiries on this, and prepared the following by way of response:

During the weekend of 8-9 October, the state of Florida was affected by a large and complex weather system, one that was not designated as a tropical or subtropical cyclone operationally by the National Hurricane Center (NHC). Watches, warnings, and forecasts for this system were provided by local National Weather Service (NWS) Weather Forecast Offices (WFOs), most notably WFO Melbourne and WFO Jacksonville, while marine analyses and forecasts were provided by NHC's Tropical Analysis and Forecast Branch (TAFB).

There have been a number of inquiries as to whether this system was a tropical or subtropical cyclone. It is not uncommon for NHC to reclassify a system after an event based on a post-storm analysis, adding it to the historical record as an unnamed tropical or subtropical cyclone. A post-storm analysis is planned for this system to see whether it met either of the following definitions:

Tropical cyclone - A warm-core non-frontal synoptic-scale cyclone, originating over tropical or subtropical waters, with organized deep convection and a closed surface wind circulation about a well-defined center. Once formed, a tropical cyclone is maintained by the extraction of heat energy from the ocean at high temperature and heat export at the low temperatures of the upper troposphere.

Subtropical cyclone - A non-frontal low pressure system that has characteristics of both tropical and extratropical cyclones. This system is typically an upper-level cold low with circulation extending to the surface layer and maximum sustained winds generally occurring at a radius of about 100 miles or more from the center. In comparison to tropical cyclones, such systems have a relatively broad zone of maximum winds that is located farther from the center, and typically have a less symmetric wind field and distribution of convection.

Nature is capable of generating a wide spectrum of low-pressure systems that don't always neatly fit into the classification systems developed by meteorologists. The weather system that affected Florida this weekend contained characteristics of both tropical and non-tropical weather systems, making its classification difficult. Because of the system's non-tropical origins, the initial warning products on the system originated from NWS WFOs, and in fact the potential impacts of this event had been advertised in WFO products up to a week in advance.

During the afternoon of 9 October, a broad area of low pressure developed off the Florida east coast. Even before this time, gale-force winds were occurring over a large area offshore, and reached the coast by the late afternoon. In some respects the system resembled a subtropical cyclone at this time. During the evening, however, the low became better defined and strengthened near the Florida coast, briefly accompanied by a very small core of strong winds more characteristic of a tropical cyclone. These winds affected the Cape Canaveral area. During the event, WFO Melbourne issued a High Wind Warning for several coastal counties and a Storm Warning for the coastal waters -both rare issuances.

The overriding consideration for NHC not to name this system during the late afternoon or evening hours was a desire to preserve the flow of watch/warning/hazard information that had been coming from the NWS WFOs. NHC coordinated warning options with the affected WFOs throughout the day Sunday. Because the hazardous weather conditions were already occurring by the time the cyclone and its circulation had become well defined, it was agreed that users would be best served by not abruptly changing the product/warning suite to tropical/subtropical issuances, with the ultimate status of the system to be determined from a post-storm analysis.

I hope this is helpful in explaining how this system was handled.

Regards,

James
--
James L. Franklin

Branch Chief, Hurricane Specialist Unit
NOAA/NWS/National Hurricane Center


Notice how he says that 93L exhibited both non-tropical and tropical characteristics. In other words, they acknowledge that it was at least partially warm-core, and likely deserves some sort of classification, but they decided to wait until after the fact in order to avoid disrupting the flow of warning products being given to the public through the local NWS WFOs. I can understand this line of reasoning, and obviously we don't know anything about how coordination between offices works and the dynamics of communicating with the public. I'm sure they were trying to keep the public's best interest in mind. I fully expect them to upgrade invest 93L to an unnamed subtropical or tropical storm after post-analysis.


Which goes well with my line of thinking when I posted a link to a previous storm and their decisions not to issue warnings (Olga 2007) for Puerto Rico. It (93L) was well handled by the WFO out of Melbourne. They issued Special Weather Statements, High Wind Warnings, Flood Warnings, etc. And that would have possibly disrupted the flow of information given out to the public at that point.

I did take a moment on Facebook to recognize the NWS Melbourne for all their hard work on this system as it came calling. They acted very quick to get information to the public as soon as things started to unfold.
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223. Gorty
18z GFS has my first Alberta Clipper for Oct. 26! Wohoo, snow before Halloween, I live in southern New England... but it also backed off on the winter storm idea for the most part for the 19th.

I think what the GFS is moreso hinting at is a colder pattern for the end of the month and on into Nov.
Member Since: November 8, 2008 Posts: 12 Comments: 1058
Quoting Skyepony:


MCV can be closed at the surface. They aren't nicknamed landcanes for being midlevel..

Subtropical storms come from ULLs that make it to the surface, extratropical storms & from Mesoscale lows. The later used to be caused a neutercane.


So if it was a Subtropical Cyclone what was it bore out of? & how long was it that before you think it should have been called a Subtropical storm & what about the Low reflecting on the surface of the GOM at the same time on Oceansat?.. 93L the tiny low was wrapped up in all that, then became the dominant low after landfall..Isn't that part of the definition of a MCC & it's MCV?




It bore out of an upper level trough over the eastern Gulf of Mexico creating divergence aloft which naturally favors rising air or convection.

Also, you forget to mention that subtropical lows can form with ULLs nearby, they do not have to be stacked over the system.
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JOVA

Enhanced Infrared (IR) Imagery (4 km Mercator)

..click image for Loop

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the GFS ecwmf and the canadian models all have a Tropical depression forming in around 110 Hrs and moving it towards western cuba and South Florida , so something to keep a close eye on
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EP102011 - Hurricane JOVA


Storm Relative 1km Geostationary Visible Imagery

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Quoting TomTaylor:

Hold on a minute there, sky.

The radar was not looking into the mid levels of the system. Mid levels of the troposphere are usually defined around 850/800mbs up to around 500mbs.

Look at the radar loop below and you will see the circulation is only 10 or 20 miles from the radar location (denoted by the white plus sign). At 10-20 miles (no, not 40 miles, check Google Earth if you don't believe me), the radar beam is less than 2,000 feet above the surface of the earth, which is absolutely not the mid levels of the Earth. It was looking aroud the 950mb level, which is the low levels of the atmosphere.





Regardless, surface observations found that the circulation was closed at the surface. Surface observations also support the fact that the circulation was not hanging around over land the whole time like you say.



Melbourne International Airport



Ocean Drive, Vero Beach



Forgot to post station TRDF1- Trident Pier, located in Port Canaveral. It showed a surface pressure of 999.5 mb and NNW winds of 2kt at 11:42pm, followed by a pressure of 999.9mb and W winds at 1kt at 11:48pm, then a pressure of 1000.0mb and SW winds at 6kt at 11:54pm. Closed circulation. Air temp went from 21C to 24C.
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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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