Category 2 Hurricane Jova hits Mexico

By: Dr. Jeff Masters , 12. lokakuuta 2011 klo 13:43 (GMT)

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Hurricane Jova slowly moved ashore over Mexico's Pacific coast at 10 pm PDT last night as a Category 2 storm with 100 mph winds. Jova was the strongest hurricane to hit Mexico's Pacific coast since Hurricane Jimena hit Baja as a Category 2 storm with 105 mph winds in 2009. Jova was a small storm at landfall, with hurricane-force winds that extended outwards only 15 miles from the center. Thus, only a relatively small stretch of coast saw Jova's most dangerous winds and storm surge. A much greater concern are Jova's rains. Satellite rainfall estimates indicate that Jova had already dumped up to six inches of rain along the coast as of 2 am EDT this morning. Jova is moving very slowly and is expected to stall out over the coast on Thursday, which will lead to extremely heavy rains over the coastal mountains of Mexico. These rains are likely to accumulate to over fifteen inches in some spots, and life-threatening flash flooding and mudslides are likely in the region of Mexico between Manzanillo and Puerto Vallarta over the next three days. Recent satellite loops show the hurricane has weakened drastically since landfall, with the eye no longer apparent and much less vigorous heavy thunderstorm activity. Jova will likely weaken to a tropical storm later today.

This year's Eastern Pacific hurricane season has been below average for number of named storms, which is typical for a La Niña year. However, an unusual number of the named storms have become hurricanes and intense hurricanes--the reverse of the situation in the Atlantic. So far in 2011, there have been 10 named storms, 9 hurricanes, 5 major hurricanes, and an Accumulated Cyclone Energy (ACE) index of 108 in the Eastern Pacific. An average year should have had 13 named storms, 7 hurricanes, 3 major hurricanes, and an ACE index of 125 by October 12. On average, the Eastern Pacific sees just two more named storms and one hurricane after October 11.


Figure 1. True-color MODIS image of Jova taken at 3:55 pm EDT October 11, 2011. At the time, Jova was a Category 2 hurricane with 100 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 received a direct hit from Jova's eye last night. His final report; "Found a small building north of La Manzanilla directly in path of Hurricane Jova's eye. No power, only iPhone battery and still cell service for now. We will get a direct hit here but no lights to see anything to film. Waves are large and crashing on building. Only going to get worse !! Sorry no photos yet, today was actually nice all day and right at dark wind picked up and knocked out power."

Puerto Vallarta webcam

Tropical Storm Irwin not expected to threaten Mexico
Tropical Storm Irwin, which is headed eastwards towards the same stretch of Mexican coast Jova is affecting, is expected to dissipate before reaching the coast. It is unlikely Irwin will bring significant rains to Mexico.

Quiet in the Atlantic
Many of the computer models continue to predict that a strong tropical disturbance capable of becoming a tropical depression could form in the Western Caribbean or extreme southern Gulf of Mexico early next week. Some of the spin and moisture for this storm could potentially come from Tropical Depression 12-E, which formed in the Eastern Pacific this morning, just offshore of the Mexico/Guatemala border. TD 12-E is expected to move inland over Southeast Mexico and Guatemala over the next few days, bringing very heavy rains of 5 - 10 inches capable of causing life-threatening flash flooding and mudslides.

Jeff Masters

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209. hcubed
13. lokakuuta 2011 klo 13:38 (GMT)
Quoting TampaSpin:
WoW has Dr. Masters Blog got slower and slower. When the Admin. keeps banning the good peeps this is the result. So sorry that many of my friends no longer blog here any more. SAD SAD!


Well, this is what many people here wanted - a totally dry, humorless weather-centered blog.

BTW, new blog...
Member Since: 18.05.2007 Posts: 289 Comments: 1639
208. PensacolaDoug
13. lokakuuta 2011 klo 07:16 (GMT)
Lots of storms, but not a lot of powerful storms. Very few landfalls the last few years and no cat5's in the ATL basin in years. Isn't this supposed to be the time of AGW? Lots of big 'canes of high intensity? Just go back and read all the crap from '04 and'05 about the future of tropical weather and the predictions of DOOM. I'm glad it hasn't materialized but I do remember Big Al and the media blaming Katrina on AGW and predicting more numerous and powerful storms would be the norm. Hard for me to take them seriously when their conclusions turn out to be so convincingly wrong. Yes the earth is warmer, but the tropics haven't responded like they said it would, so how do we know any of their other predictions about AGW will be right 50 to 100 years from now when they can't even get a 5 year forecast right? We need serious, unbiased research without a politcal agenda. The issue is too important to get wrong. My two cents. G'night.
Member Since: 25.07.2006 Posts: 0 Comments: 519
207. AussieStorm
13. lokakuuta 2011 klo 06:57 (GMT)
Storm kills four in western Mexico

The powerful storm system Jova has killed four people in Mexico and is still packing strong gusts a day after making landfall.

The system had roared ashore in Jalisco state on Tuesday as a category two hurricane, but late on Wednesday had weakened to a remnant of the powerful system it once was.

At least four people were confirmed dead on Wednesday, including when a 21-year-old woman and her five-year-old daughter were swept away by flood waters in Jalisco.

An air rescue meanwhile saved 39 people threatened by rising waters in the state, officials said.

Despite rapidly losing its punch, Jova was still packing strong gusts a day after making landfall, with sustained winds topping 45km/h.

Jova uprooted trees and knocked down protective walls as it lashed western Mexico, with officials warning of flash floods and mudslides.

The system was moving inland at about 9km/h and was expected to weaken further, eventually dissipating on Thursday, but Jova's 'heavy rainfall remains a major threat', the Miami-based National Hurricane Centre said.

Despite the downgrade, Jova could deposit as much as a half-metre of rain in some areas, with downpours creating perilous conditions in parts of the popular tourist destination of southwestern Mexico.

The heavy precipitation could cause 'life-threatening flash floods and mudslides over steep terrain', the NHC said.

Meanwhile to the south, at least 19 people were killed when torrential rains brought by a separate storm system hit large swaths of Central America, with more than 40,000 people hit by flooding and landslides.

Guatemala was worst hit by the heavy rains dumped by tropical depression '12-E', with President Alvaro Colom saying at least 13 people were killed, while El Salvador recorded two deaths and Nicaragua saw at least four deaths.

Jova battered Mexico just as thousands of athletes from around the world began arriving for the Pan American Games, which begin on Friday in Guadalajara, the Jalisco state capital more than 100km from the coast.

Authorities have insisted the games, one of the premier events on the global sports calendar, would not be affected.

Mexican troops on Wednesday patrolled the streets of Manzanillo, some 800km west of Mexico City where the storm crashed ashore. Some of the busy port was under more than a metre of water, according to an AFP photographer.

All port and marine activity has been halted there, and several beachfront restaurants were under threat as a retaining wall collapsed.

Several communities experienced power outages and some schools cancelled classes on Wednesday, while 170 people living in high-risk areas moved to shelters.

Several major storms or hurricanes have buffeted Mexico's Pacific coast in recent months but most have remained offshore.

The season's first named storm, Arlene, left at least 16 people dead and drenched much of the country in July.

Tropical storms and hurricanes last year caused flooding and mudslides in Mexico that killed 125 people, left hundreds of thousands homeless and caused more than $US4 billion ($A3.95 billion) in damage.
Member Since: 30.09.2007 Posts: 9 Comments: 15742
206. AussieStorm
13. lokakuuta 2011 klo 06:46 (GMT)
Damage in Bali from 6.0 Quake at 13 Oct 2011 11:16.











Dozens injured in Bali quake

Indonesia's resort island of Bali was struck by a 6.0 magnitude earthquake today, shaking buildings and sending tourists running out of hotels.

The epicentre of the quake was about 160 km southwest of the island's capital Denpasar, the US Geological Survey said.

The quake was strong enough to be felt on the neighbouring islands of Java and Lombok.

A spokesperson for the local hospital said at least 50 people were hurt, many with cuts, broken bones and head wounds.

Three people were in critical condition.

Caroline Mercier, a 40-year-old tourist in the island's cultural centre of Ubud, said she was used to feeling quakes in California, but never like this one.

"It started at my feet and went all though my heart and head - it made me nauseous. My first reaction was to get out of the house. I was very confused when the roof started shaking," she told Reuters.

Novotel Bali Benoa, one of the many resorts in the luxury southern beach area of Nusa Dua, evacuated its guests as the hotel shook for a minute.

"The funny thing is that the foreign guests who were sitting in the lobby did not feel the shaking. They started running when hearing people say 'there's an earthquake' while running down the lobby," hotel worker Ariyanti told Reuters.

Endro Tjahjono, head of information at Bali's meteorology agency, said there was no tsunami potential and no reports of aftershocks. Cracks appeared in the walls and glass lobby windows of his office in the southern town of Kuta, and some top floor ceilings fell off, he said.

Indonesia is on the Pacific's "Rim of Fire" and gets regular earthquakes.

Member Since: 30.09.2007 Posts: 9 Comments: 15742
205. SubtropicalHi
13. lokakuuta 2011 klo 06:39 (GMT)
Quoting redwagon:

Look at all of Jova's moisture.... going to FL.


LOL..TX just can't squeeze a drop out of anything tropical, even our "old reliable", EPac.
Member Since: 27.06.2010 Posts: 1 Comments: 374
204. robert88
13. lokakuuta 2011 klo 05:42 (GMT)
Not much going on with the 00Z GFS...weak LP's. The MJO has been hanging around over in the W Pacific for a while. Looks like it might take a little longer to migrate towards the Atlantic basin. I think if we even get any decent storms or canes it will be closer towards the end of the month.



Member Since: 22.05.2010 Posts: 0 Comments: 907
203. redwagon
13. lokakuuta 2011 klo 04:49 (GMT)
Quoting TampaSpin:


Yep i see that.....It appears to come from the Pacific side.

Look at all of Jova's moisture.... going to FL.
Member Since: 4.08.2007 Posts: 0 Comments: 2791
202. will40
13. lokakuuta 2011 klo 04:45 (GMT)
low off NC at 288 hrs
Member Since: 19.09.2005 Posts: 2 Comments: 4066
201. GTcooliebai
13. lokakuuta 2011 klo 04:40 (GMT)
Quoting AussieStorm:



As of 2pm Hurricane Irene at 31.2N 77.5W
Aha, so it's 77.5 W. anything that formed west of that longitude in the Atlantic Basin has not reached Hurricane strength so far this season. Thanks Aussie! :)
Member Since: 31.08.2009 Posts: 0 Comments: 5628
200. TampaSpin
13. lokakuuta 2011 klo 04:30 (GMT)
Quoting TomTaylor:
really quick, latest GFS (0z) develops a low just east of the Yucatan peninsula in just 3/4 days.


Yep i see that.....It appears to come from the Pacific side.
Member Since: 2.09.2007 Posts: 177 Comments: 20430
199. TomTaylor
13. lokakuuta 2011 klo 04:24 (GMT)
really quick, latest GFS (0z) develops a low just east of the Yucatan peninsula in just 3/4 days.
Member Since: 24.08.2010 Posts: 19 Comments: 4357
198. TampaSpin
13. lokakuuta 2011 klo 04:19 (GMT)
WoW has Dr. Masters Blog got slower and slower. When the Admin. keeps banning the good peeps this is the result. So sorry that many of my friends no longer blog here any more. SAD SAD!
Member Since: 2.09.2007 Posts: 177 Comments: 20430
197. TomTaylor
13. lokakuuta 2011 klo 04:19 (GMT)
Quoting BaltimoreBrian:


Thanks TomTaylor. You did a really good job of explaining without false certainty. I like that.
no problem
Member Since: 24.08.2010 Posts: 19 Comments: 4357
196. TomTaylor
13. lokakuuta 2011 klo 04:17 (GMT)
Quoting TampaSpin:


Thanks Tom........great discussion!
No problem, hope things are well in Florida.

I gotta go do some hw, later
Member Since: 24.08.2010 Posts: 19 Comments: 4357
195. TampaSpin
13. lokakuuta 2011 klo 04:13 (GMT)
Quoting TomTaylor:
Yes it is interesting. MJO appears to be in a relatively low amplitude at this time and has been for about a year now. Unfortunately, it does not cycle regularly and not much is known about what regulates it's strength.



Thanks Tom........great discussion!
Member Since: 2.09.2007 Posts: 177 Comments: 20430
194. AussieStorm
13. lokakuuta 2011 klo 04:10 (GMT)
Quoting AussieStorm:
Region: SOUTH OF BALI, INDONESIA
Geographic coordinates: 9.359S, 114.647E
Magnitude: 6.0 Mw
Depth: 61 km
Universal Time (UTC): 13 Oct 2011 03:16:32
Time near the Epicenter: 13 Oct 2011 11:16:32
Local standard time in your area: 13 Oct 2011 03:16:32

Location with respect to nearby cities:
100 km (62 miles) SW (220 degrees) of Denpasar, Bali, Indonesia
161 km (100 miles) W (273 degrees) of Mataram, Lombok, Indonesia
170 km (105 miles) SE (145 degrees) of Jember, Java, Indonesia
941 km (585 miles) ESE (113 degrees) of JAKARTA, Java, Indonesia


Hearing reports of significant damage to buildings in South Bali. Cracks in walls, collapsed balconies



Member Since: 30.09.2007 Posts: 9 Comments: 15742
193. AussieStorm
13. lokakuuta 2011 klo 04:07 (GMT)
Member Since: 30.09.2007 Posts: 9 Comments: 15742
192. AussieStorm
13. lokakuuta 2011 klo 04:05 (GMT)
Quoting AussieStorm:

Temples collapse in Bali after 6.8 magnitude quake.

Quake claims casualties in some cities and regencies in East Java.
Member Since: 30.09.2007 Posts: 9 Comments: 15742
191. TomTaylor
13. lokakuuta 2011 klo 04:05 (GMT)
Quoting TampaSpin:


Do you not find it strange tho that his year MJO seemed to not have any affect on the Atlantic side at all.....Seems we never really got the MJO uplift going in the Atlantic.
Yes it is interesting. MJO appears to be in a relatively low amplitude at this time and has been for about a year now. Unfortunately, it does not cycle regularly and not much is known about what regulates it's strength.

Member Since: 24.08.2010 Posts: 19 Comments: 4357
190. AussieStorm
13. lokakuuta 2011 klo 04:05 (GMT)
Quoting AussieStorm:
Region: SOUTH OF BALI, INDONESIA
Geographic coordinates: 9.359S, 114.647E
Magnitude: 6.0 Mw
Depth: 61 km
Universal Time (UTC): 13 Oct 2011 03:16:32
Time near the Epicenter: 13 Oct 2011 11:16:32
Local standard time in your area: 13 Oct 2011 03:16:32

Location with respect to nearby cities:
100 km (62 miles) SW (220 degrees) of Denpasar, Bali, Indonesia
161 km (100 miles) W (273 degrees) of Mataram, Lombok, Indonesia
170 km (105 miles) SE (145 degrees) of Jember, Java, Indonesia
941 km (585 miles) ESE (113 degrees) of JAKARTA, Java, Indonesia


Hearing reports of significant damage to buildings in South Bali. Cracks in walls, collapsed balconies


Temples collapse in Bali after 6.8 magnitude quake.
Member Since: 30.09.2007 Posts: 9 Comments: 15742
189. TampaSpin
13. lokakuuta 2011 klo 04:00 (GMT)
Quoting TomTaylor:
La Nina has been favored because we are in a cold PDO phase.

And I'm going to say it's because the globe is warmer, therefore more evaporation occurs putting more water in the atmosphere


Do you not find it strange tho that his year MJO seemed to not have any affect on the Atlantic side at all.....Seems we never really got the MJO uplift going in the Atlantic.
Member Since: 2.09.2007 Posts: 177 Comments: 20430
188. sunlinepr
13. lokakuuta 2011 klo 03:59 (GMT)
The other day I was asking myself:

Why doesn't the NHC forecasts Nontropical Lows / Winter storms the same way it does with Tropical systems...

I wrote an email to the NHC...

NHC:
It has been my question for years.... Why doesn't the NHC names Winter storms and acquires data the same way it does during the Hurricane season.... Not only that would incentivate weather science and jobs, but would build a knowledge base that has proven to be related to discuss global weather....

Thanks, sunlinepr



Well, they responded me:


Hello sunlinepr:

Thank you for your e-mail.

The National Hurricane Center does not make forecasts for non-tropical areas of low pressure, including winter storms.
While winter storms are not named, they have been classified on a scale, since 2006.
See http://www.noaanews.noaa.gov/stories2006/s2567.htm

In addition, hurricane hunter aircraft does fly into winter storms, adding to the accuracy of the forecasts:
See http://www.publicaffairs.noaa.gov/grounders/winter aircraft.html

Regards,

Dennis Feltgen
Public Affairs Officer
Meteorologist
NOAA Communications & External Affairs
National Hurricane Center
Miami, Florida
Member Since: 2.08.2010 Posts: 21 Comments: 9648
187. AussieStorm
13. lokakuuta 2011 klo 03:58 (GMT)
Region: SOUTH OF BALI, INDONESIA
Geographic coordinates: 9.359S, 114.647E
Magnitude: 6.0 Mw
Depth: 61 km
Universal Time (UTC): 13 Oct 2011 03:16:32
Time near the Epicenter: 13 Oct 2011 11:16:32
Local standard time in your area: 13 Oct 2011 03:16:32

Location with respect to nearby cities:
100 km (62 miles) SW (220 degrees) of Denpasar, Bali, Indonesia
161 km (100 miles) W (273 degrees) of Mataram, Lombok, Indonesia
170 km (105 miles) SE (145 degrees) of Jember, Java, Indonesia
941 km (585 miles) ESE (113 degrees) of JAKARTA, Java, Indonesia


Hearing reports of significant damage to buildings in South Bali. Cracks in walls, collapsed balconies

Member Since: 30.09.2007 Posts: 9 Comments: 15742
186. TomTaylor
13. lokakuuta 2011 klo 03:58 (GMT)
Quoting TampaSpin:


It appears to me that most of the above normal moisture occurred at the equator. With that said and looking off in the Pacific it appears that probably LaNina which has been with us mostly during this time may have had something to do with it. But, i'm sure your gonna say the melting of the Ice Capps which is also possible cause.
La Nina has been favored because we are in a cold PDO phase.

And I'm going to say it's because the globe is warmer, therefore more evaporation occurs putting more water in the atmosphere
Member Since: 24.08.2010 Posts: 19 Comments: 4357
185. TampaSpin
13. lokakuuta 2011 klo 03:56 (GMT)
Quoting TomTaylor:

Well looking at total precipitable water anomalies anomalies over the entire globe for the last five years (2005-2010) versus the 1980-2010 average, we have already had above average humidity across the entire global atmosphere, just as AGW theory predicted.




And to the bold, why's that?



It appears to me that most of the above normal moisture occurred at the equator. With that said and looking off in the Pacific it appears that probably LaNina which has been with us mostly during this time may have had something to do with it. But, i'm sure your gonna say the melting of the Ice Capps which is also possible cause.
Member Since: 2.09.2007 Posts: 177 Comments: 20430
184. AussieStorm
13. lokakuuta 2011 klo 03:47 (GMT)
Quoting GTcooliebai:
Thanks for posting the chart above because I have a question for you, how far west in longitude did Hurricane Irene come before recurving?



As of 2pm Hurricane Irene at 31.2N 77.5W
Member Since: 30.09.2007 Posts: 9 Comments: 15742
183. TomTaylor
13. lokakuuta 2011 klo 03:41 (GMT)
Quoting TampaSpin:


I did not forget anything. I was thinking of the entire globe. I just don't see the increase moisture over the Globe IMO. MJO should show up much more as an example i would think.

Well looking at total precipitable water anomalies anomalies over the entire globe for the last five years (2005-2010) versus the 1980-2010 average, we have already had above average humidity across the entire global atmosphere, just as AGW theory predicted.




And to the bold, why's that?

Member Since: 24.08.2010 Posts: 19 Comments: 4357
182. TampaSpin
13. lokakuuta 2011 klo 03:30 (GMT)
Quoting TomTaylor:
You forget that I am only looking at the tropical Atlantic, not the entire globe.

It's global warming, not tropical Atlantic warming. A warmer world would favor increased evaporation. Of course, a warmer atmosphere would also require more moisture to reach equal relative humidity levels relative to a cooler atmosphere.


I did not forget anything. I was thinking of the entire globe. I just don't see the increase moisture over the Globe IMO. MJO should show up much more as an example i would think.
Member Since: 2.09.2007 Posts: 177 Comments: 20430
181. TomTaylor
13. lokakuuta 2011 klo 03:27 (GMT)
Quoting TampaSpin:


Not that i wanna start a GW debate, but hasn't most GW activist state that more moisture would result from GW. I do believe that is what most are saying!
You forget that I am only looking at the tropical Atlantic, not the entire globe.

It's global warming, not tropical Atlantic warming. A warmer world would favor increased evaporation. Of course, a warmer atmosphere would also require more moisture to reach equal relative humidity levels relative to a cooler atmosphere.
Member Since: 24.08.2010 Posts: 19 Comments: 4357
180. TampaSpin
13. lokakuuta 2011 klo 03:26 (GMT)
Quoting FrankZapper:
So what your saying is that there was high pressure ( higher than normal) over the tropics.


I don't buy the dry air theory. The truth is nobody knows why things were slower than predicted.


How can anyone say things are slower than Predicted. Its been very active. Just not much in Land Threats.
Member Since: 2.09.2007 Posts: 177 Comments: 20430
179. TomTaylor
13. lokakuuta 2011 klo 03:26 (GMT)
Quoting FrankZapper:
So what your saying is that there was high pressure ( higher than normal) over the tropics.


I don't buy the dry air theory. The truth is nobody knows why things were slower than predicted.
No that's not exactly what I am saying. Surface pressures have been below average over the tropical Atlantic. You are right that pressures have been higher (not at the surface, but at the mid levels) over the tropical Atlantic which would further support the idea of less vertical instability/convection over the region.

If you don't like my theory, that's fine, but please understand vertical instability is determined by temperature and humidity. Since temperature anomalies over the tropical Atlantic favor increased instability, the only thing that could explain the lack of instability would be the humidity levels. Sure enough, according to the PSD reanalysis data, humidity levels over the tropical Atlantic have been below average.
Member Since: 24.08.2010 Posts: 19 Comments: 4357
178. TampaSpin
13. lokakuuta 2011 klo 03:25 (GMT)
Quoting TomTaylor:
A variety of reasons. It's incorrect to pinpoint any one reason because everything really has an effect on everything else in earth's atmosphere (and ecosystems). Everything is connected and impact by something else.

With that said, most likely more sinking air than usual would explain the lack of moisture in the atmosphere. Dry air doesn't just show up, there has to be a reason. Since the SSTs have been warmer than normal over the tropical Atlantic (which would favor increased moisture in the atmosphere) it must be a process with the atmosphere which is causing the abnormally dry air over the region. Since SSTs are above average, the best explanation for the drier atmosphere over the deep tropics must be anomalous sinking air over the region...As air sinks, it warms by compression causing relative humidity to drop, further decreasing vertical instability.

Possible explanations for this could be the ENSO, which, although it has been neutral over the nino regions as a whole, has been very positive (warm/El Nino like) in the regions right off central America/South America creating increased convection/vertical instability, favoring sinking air over our tropical Atlantic region. Proof of the El Nino being around average as a whole but very positive near the central America region can be seen with the very intense tropical storms the epac has seen meanwhile the central pac hasn't had a single storm yet.

Other explanations could be the QBO, the relatively low amplitude of the MJO over the season, mid latitude teleconnections, and other reasons I can't think of right now.


Not that i wanna start a GW debate, but hasn't most GW activist state that more moisture would result from GW. I do believe that is what most are saying!
Member Since: 2.09.2007 Posts: 177 Comments: 20430
177. BaltimoreBrian
13. lokakuuta 2011 klo 03:23 (GMT)
Quoting TomTaylor:
A variety of reasons. It's incorrect to pinpoint any one reason because everything really has an effect on everything else in earth's atmosphere (and ecosystems). Everything is connected and impact by something else.

With that said, most likely more sinking air than usual would explain the lack of moisture in the atmosphere. Dry air doesn't just show up, there has to be a reason. Since the SSTs have been warmer than normal over the tropical Atlantic (which would favor increased moisture in the atmosphere) it must be a process with the atmosphere which is causing the abnormally dry air over the region. Since SSTs are above average, the best explanation for the drier atmosphere over the deep tropics must be anomalous sinking air over the region...As air sinks, it warms by compression causing relative humidity to drop, further decreasing vertical instability.

Possible explanations for this could be the ENSO, which, although it has been neutral over the nino regions as a whole, has been very positive (warm/El Nino like) in the regions right off central America/South America creating increased convection/vertical instability, favoring sinking air over our tropical Atlantic region. Proof of the El Nino being around average as a whole but very positive near the central America region can be seen with the very intense tropical storms the epac has seen meanwhile the central pac hasn't had a single storm yet.

Other explanations could be the QBO, the relatively low amplitude of the MJO over the season, mid latitude teleconnections, and other reasons I can't think of right now.


Thanks TomTaylor. You did a really good job of explaining without false certainty. I like that.
Member Since: 9.08.2011 Posts: 25 Comments: 7993
176. FrankZapper
13. lokakuuta 2011 klo 03:23 (GMT)
Quoting TomTaylor:
A variety of reasons. It's incorrect to pinpoint any one reason because everything really has an effect on everything else in earth's atmosphere (and ecosystems). Everything is connected and impact by something else.

With that said, most likely more sinking air than usual would explain the lack of moisture in the atmosphere. Dry air doesn't just show up, there has to be a reason. Since the SSTs have been warmer than normal over the tropical Atlantic (which would favor increased moisture in the atmosphere) it must be a process with the atmosphere which is causing the abnormally dry air over the region. Since SSTs are above average, the best explanation for the drier atmosphere over the deep tropics must be anomalous sinking air over the region...As air sinks, it warms by compression causing relative humidity to drop, further decreasing vertical instability.

Possible explanations for this could be the ENSO, which, although it has been neutral over the nino regions as a whole, has been very positive (warm/El Nino like) in the regions right off central America/South America creating increased convection/vertical instability, favoring sinking air over our tropical Atlantic region. Proof of the El Nino being around average as a whole but very positive near the central America region can be seen with the very intense tropical storms the epac has seen meanwhile the central pac hasn't had a single storm yet.

Other explanations could be the QBO, the relatively low amplitude of the MJO over the season, mid latitude teleconnections, and other reasons I can't think of right now.
So what your saying is that there was high pressure ( higher than normal) over the tropics.


I don't buy the dry air theory. The truth is nobody knows why things were slower than predicted.
Member Since: 26.05.2011 Posts: 0 Comments: 1193
175. TampaSpin
13. lokakuuta 2011 klo 03:22 (GMT)
We got a couple areas of Low Level Spin Starting...

Member Since: 2.09.2007 Posts: 177 Comments: 20430
174. TomTaylor
13. lokakuuta 2011 klo 03:04 (GMT)
Quoting BaltimoreBrian:



Why do you think the atmosphere over the tropical Atlantic was drier than normal?
A variety of reasons. It's incorrect to pinpoint any one reason because everything really has an effect on everything else in earth's atmosphere (and ecosystems). Everything is connected and impact by something else.

With that said, most likely more sinking air than usual would explain the lack of moisture in the atmosphere. Dry air doesn't just show up, there has to be a reason. Since the SSTs have been warmer than normal over the tropical Atlantic (which would favor increased moisture in the atmosphere) it must be a process with the atmosphere which is causing the abnormally dry air over the region. Since SSTs are above average, the best explanation for the drier atmosphere over the deep tropics must be anomalous sinking air over the region...As air sinks, it warms by compression causing relative humidity to drop, further decreasing vertical instability.

Possible explanations for this could be the ENSO, which, although it has been neutral over the nino regions as a whole, has been very positive (warm/El Nino like) in the regions right off central America/South America creating increased convection/vertical instability, favoring sinking air over our tropical Atlantic region. Proof of the El Nino being around average as a whole but very positive near the central America region can be seen with the very intense tropical storms the epac has seen meanwhile the central pac hasn't had a single storm yet.

Other explanations could be the QBO, the relatively low amplitude of the MJO over the season, mid latitude teleconnections, and other reasons I can't think of right now.
Member Since: 24.08.2010 Posts: 19 Comments: 4357
173. GTcooliebai
13. lokakuuta 2011 klo 02:52 (GMT)
We haven't had a Cat. 5 Hurricane in the Atlantic since 2007. Didn't realize until now that Dean & Felix had winds of 175 mph at their peaks :o
Member Since: 31.08.2009 Posts: 0 Comments: 5628
172. GTcooliebai
13. lokakuuta 2011 klo 02:48 (GMT)
Quoting Chicklit:
Well, the season isn't over until the fat lady can't sing anymore. haha.



I'm rooting for the western caribbean to spin something up. It's hot down there.
Thanks for posting the chart above because I have a question for you, how far west in longitude did Hurricane Irene come before recurving?
Member Since: 31.08.2009 Posts: 0 Comments: 5628
171. wunderweatherman123
13. lokakuuta 2011 klo 02:44 (GMT)
jova and td 12 are remnant lows now. irwin down to a td again expected to dissipate tomorrow. we are back in a LULL :P we will see what october brings although personally im not expecting much :P we will see though we hav 18 days left of october 1 to 3 named storms is possible and 1 in november is possbile so an additional 2 to 5 storms is possible
Member Since: 23.08.2011 Posts: 0 Comments: 1243
170. Chicklit
13. lokakuuta 2011 klo 02:39 (GMT)
Well, the season isn't over until the fat lady can't sing anymore. haha.



I'm rooting for the western caribbean to spin something up. It's hot down there.
Member Since: 11.07.2006 Posts: 14 Comments: 11034
169. wunderweatherman123
13. lokakuuta 2011 klo 02:38 (GMT)
Quoting TropicalAnalystwx13:

I'd hate to see what this season would've looked like if we had high vertical instability.
honeslty it would be very similar to 2010. pretty similar steering only this year we had one storm miss a trough (irene) and the Gulf Ridge didnt block lousiana and texas from don and lee but pretty similar to 2010 for the numbers :P
Member Since: 23.08.2011 Posts: 0 Comments: 1243
168. GTcooliebai
13. lokakuuta 2011 klo 02:33 (GMT)
Quoting Chicklit:

But what are the SST's? And it's still hot here.
We may have a couple of weeks left.
Well I guess it is not out of the question we could see another Ida, but that happened during El Nino. I must say Ida did well considering the extreme wind shear that was going on in the GOM at the time. Her remnants even produced a Nor'Easter. Quite a fascinating storm if you think about it.
Member Since: 31.08.2009 Posts: 0 Comments: 5628
167. Chicklit
13. lokakuuta 2011 klo 02:31 (GMT)
Quoting BaltimoreBrian:



Why do you think the atmosphere over the tropical Atlantic was drier than normal?

We've seen 2 years of dry ULL's killing systems close to the conus imo.
I'm probably wrong, but it seems that way.
Just look at the Gulf now.


Although it does look like moisture might be getting a ground hold. We'll see if it is too late.
Link
Member Since: 11.07.2006 Posts: 14 Comments: 11034
166. BaltimoreBrian
13. lokakuuta 2011 klo 02:28 (GMT)
Quoting TomTaylor:
Agreed, and I'd explain the lack of instability over the Tropical Atlantic with the fact that the atmosphere over the region has been drier than normal.

PSD Reanalysis for June to September 2011 shows that nearly every level of the atmosphere from about 15N down to the equator (the deep tropics of the Atlantic) was drier than average in terms of both relative and specific humidity. Equally telling is the total precipitable water product which shows basically the exact same thing (everywhere from around 15N to the equator was drier than normal over the tropical Atlantic for the given time period).

This points to the idea that the deep tropics over the tropical Atlantic have been unusually dry, resulting in a lack of vertical instability. While temperatures also factor into vertical instability, if you check the temperature profile over the tropical Atlantic you will see that it has been warmer than average at the surface to mid levels, and cooler than average from the 200mb level and up (except over the Gulf of Mexico) which means that if anything, June to September 2011 temperature anomalies should have favored increased vertical instability.


To add on to this...

Not surprisingly, when we look at the activity so far over the deep tropics (15N to the equator) of the Atlantic, you'll see we haven't had a single hurricane over that region. All of our hurricanes and major hurricanes have occurred north of 15N, or outside of the deep tropics (except Katia which only briefly made it to hurricane status over the deep tropics). Sure enough, these regions are mostly above average in terms of atmospheric humidity.






Why do you think the atmosphere over the tropical Atlantic was drier than normal?
Member Since: 9.08.2011 Posts: 25 Comments: 7993
165. Chicklit
13. lokakuuta 2011 klo 02:27 (GMT)
Quoting GTcooliebai:
You know what it could be over for us here in the States, just looking back at a couple La Nina years in the last decade, and I can't find a storm that hit the US after Oct. 24th which was Wilma, this excluding El Nino years. You have to go all the way back to Mitch in '98 to see a storm hit the States which was Nov. 5th, ironically in Naples where basically Wilma struck.

But what are the SST's? And it's still hot here.
We may have a couple of weeks left.
The dry air is a killer though.
That may be what snuffs us out.
Even if a system gets started, if the dry air intrudes, it's curtains.
Member Since: 11.07.2006 Posts: 14 Comments: 11034
164. TropicalAnalystwx13
13. lokakuuta 2011 klo 02:26 (GMT)
Quoting TomTaylor:
Agreed, and I'd explain the lack of instability over the Tropical Atlantic with the fact that the atmosphere over the region has been drier than normal.

PSD Reanalysis for June to September 2011 shows that nearly every level of the atmosphere from about 15N down to the equator (the deep tropics of the Atlantic) was drier than average in terms of both relative and specific humidity. Equally telling is the total precipitable water product which shows basically the exact same thing (everywhere from around 15N to the equator was drier than normal over the tropical Atlantic for the given time period).

This points to the idea that the deep tropics over the tropical Atlantic have been unusually dry, resulting in a lack of vertical instability. While temperatures also factor into vertical instability, if you check the temperature profile over the tropical Atlantic you will see that it has been warmer than average at the surface to mid levels, and cooler than average from the 200mb level and up (except over the Gulf of Mexico) which means that if anything, June to September 2011 temperature anomalies should have favored increased vertical instability.


To add on to this...

Not surprisingly, when we look at the activity so far over the deep tropics (15N to the equator) of the Atlantic, you'll see we haven't had a single hurricane over that region. All of our hurricanes and major hurricanes have occurred north of 15N, or outside of the deep tropics. Sure enough, these regions are mostly above average in terms of atmospheric humidity.




I'd hate to see what this season would've looked like if we had high vertical instability.
Member Since: 6.07.2010 Posts: 108 Comments: 30242
163. GTcooliebai
13. lokakuuta 2011 klo 02:21 (GMT)
Quoting Chicklit:
Looks like 12E will dissipate over Mexico.
There's a tropical wave out by Cape Verde.
I'm not quite ready to write off the season yet.
It's still hot here in Florida.
Maybe once this forecasted cold front comes through we can write the obit for for hurricane season 2011.
You know what it could be over for us here in the States, just looking back at a couple La Nina years in the last decade, and I can't find a storm that hit the US after Oct. 24th which was Wilma, this excluding El Nino years. You have to go all the way back to Mitch in '98 to see a storm hit the States which was Nov. 5th, ironically in Naples where basically Wilma struck.
Member Since: 31.08.2009 Posts: 0 Comments: 5628
162. TomTaylor
13. lokakuuta 2011 klo 02:20 (GMT)
Quoting MiamiHurricanes09:
I don't think that there has ever been an Atlantic hurricane season in which we saw more than 15 tropical storms develop, yet only 5 of those tropical storms be able to intensify into hurricanes. This implies that although a bunch of names got check-marked, this season turns out to be a pretty much average one. In my opinion, this is likely due to the lack of instability that was noted throughout the basin for most of the season.
Agreed, and I'd explain the lack of instability over the Tropical Atlantic with the fact that the atmosphere over the region has been drier than normal.

PSD Reanalysis for June to September 2011 shows that nearly every level of the atmosphere from about 15N down to the equator (the deep tropics of the Atlantic) was drier than average in terms of both relative and specific humidity. Equally telling is the total precipitable water product which shows basically the exact same thing (everywhere from around 15N to the equator was drier than normal over the tropical Atlantic for the given time period).

This points to the idea that the deep tropics over the tropical Atlantic have been unusually dry, resulting in a lack of vertical instability. While temperatures also factor into vertical instability, if you check the temperature profile over the tropical Atlantic you will see that it has been warmer than average at the surface to mid levels, and cooler than average from the 200mb level and up (except over the Gulf of Mexico) which means that if anything, June to September 2011 temperature anomalies should have favored increased vertical instability.


To add on to this...

Not surprisingly, when we look at the activity so far over the deep tropics (15N to the equator) of the Atlantic, you'll see we haven't had a single hurricane over that region. All of our hurricanes and major hurricanes have occurred north of 15N, or outside of the deep tropics (except Katia which only briefly made it to hurricane status over the deep tropics). Sure enough, these regions are mostly above average in terms of atmospheric humidity.



Member Since: 24.08.2010 Posts: 19 Comments: 4357
161. FrankZapper
13. lokakuuta 2011 klo 02:17 (GMT)
Quoting Neapolitan:

That'd be about on time for us here in South Florida if it makes it this far; our first real cold front historically makes its way to us sometime during the last ten days of October. FWIW, the 10-day forecast for Atlanta shows low in the low 40s by the end of next week; Cincinnati shows a low in the 30s; and International Falls down into the 20s.

It's that time of year, I suppose...
Doc, I haven't seen you lately. Lecturing late at The University?
Member Since: 26.05.2011 Posts: 0 Comments: 1193
160. TropicalAnalystwx13
13. lokakuuta 2011 klo 02:14 (GMT)
Quoting wunderweatherman123:
well if u guys were wundering why we havent gotten an ivan gustav or frances track its because of the troughing off the east coast since 2009. A WSI meteorologist said its been there for 3 years but that doesnt mean i will change. if we dont get el nino next year then we could see active numbers AND if vertical instability remains avergae we will get more hurricanes and majors. What I dont like is that before the 2011 season many pointed out the US will receive at least 3 landfalling hurricanes.. that didnt come true but we still got one bad one. what important to pay attention is the enso and steering flow, not statements that arent facts such as " 2011 will be the year the US gets nailed" these are predictions. right now we are -0.9C in the nino 3.4 region 1 degree shy of a moderate la nina

You can breathe now.
Member Since: 6.07.2010 Posts: 108 Comments: 30242
159. Chicklit
13. lokakuuta 2011 klo 02:11 (GMT)
I don't think the western caribbean would mind a little action at this point. And definitely Texas has not had enough rain.
Such an odd year for extreme weather events: the mad tornado outbreak, the washington, d.c. earthquake followed by um (?) (was in the hospital at that time for planned visit...sorry), the intense flooding along the Ohio and Mississippi Rivers and the east coast... however, hurricane activity is suppressed. We would consider ourselves lucky if not for the droughts.

Did 93L dump much rain in the Panhandle?
Our trees are happy here in ECFL. We finally got some decent rain out of the invest-whatever-it-was.
Member Since: 11.07.2006 Posts: 14 Comments: 11034

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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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