Little change to 99L, which remains very close to tropical depression status

By: Dr. Jeff Masters , 7:11 PM GMT on October 20, 2010

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A tropical disturbance (Invest 99L) centered 160 miles southwest of the Cayman Islands is moving south to southeast at 5 - 10 mph. A Hurricane Hunter flight arrived in the storm at about 11am this morning, and found a closed circulation with top winds at flight level (700 feet) of 33 mph. A closed circulation and 30 mph surface winds are necessary conditions for a tropical depression to exist, but the storm must also have a great deal of heavy thunderstorm activity near the center that persists for many hours. In the judgment of NHC, 99L does not qualify as a tropical depression in that regard. The storm is bringing heavy rain to the Cayman Islands; 4.14" inches has fallen over the past 2 1/2 days at Savannah on Grand Cayman Island. Heavy rains have diminished over the Cayman Islands, but have spread to western Jamaica and west-central Cuba this afternoon. Recent satellite imagery shows that the surface circulation center is exposed to view, and 99L has a relatively meager amount of heavy thunderstorm activity. The center is more than 80 miles west of the heaviest thunderstorm activity, and it is likely that 99L's center will relocate itself to the east to be more underneath the heaviest thunderstorms. Wind shear is marginal for development, 15 - 20 knots, due to the clockwise flow of air around an upper-level high pressure system near the coast of Honduras. The high is bringing strong upper-level winds out of the southwest to 99L. Water vapor satellite loops show considerable dry air to the west and north of 99L, and the strong southwesterly winds over the storm are bringing some of this dry into into the core of the storm, keeping all the heavy thunderstorm development confined to the east side of the center. The waters beneath 99L are very warm, 29°C, but 99L will not be able to take advantage of these warm waters until the shear relaxes. A new hurricane hunter aircraft will be in the storm tonight near 8pm EDT.

Forecast for 99L
The current southward movement of 99L is carrying the storm into a region of lower wind shear, and we should see 99L accumulate more heavy thunderstorm activity near its center beginning tonight. The latest SHIPS model forecast predicts that wind shear over the Western Caribbean will decline below 15 knots Thursday afternoon through Saturday afternoon, which should allow the storm to become a tropical depression by Thursday. Steering currents will be weak today through Friday in the Western Caribbean, making it difficult to predict where 99L may go. The models are split into two camps, with the GFDL and HWRF models taking 99L to the west-northwest over the western tip of Cuba or the Yucatan Peninsula on Sunday as a hurricane. The rest of the models take 99L to the south over Honduras on Sunday, and keep the storm below hurricane strength. Given 99L's current southward motion and the possibility that the center will relocate farther to the east later today, this makes a track to the southwest towards Honduras more likely, I predict. NHC is giving 99L a 70% chance of developing into a tropical depression by Friday, which is a reasonable forecast. I expect this will become Tropical Storm Richard by Friday.


Figure 1. Afternoon satellite image of Invest 99L.

Death toll from Super Typhoon Megi in the Philippines remarkably low
The power is still out and communications are down over the majority of the northern portion of the Philippines' Luzon Island blasted by Typhoon Megi yesterday, so the full extent of the destruction wrought by the great storm is still unclear. However, the death toll from the great storm stands at only 19, reflecting the superior effort Philippines officials made to evacuate low-lying areas and get people out of locations prone to flash flooding and mudslides. Previous major typhoons to strike the Philippines have nearly always killed hundreds, and sometime thousands, so the preparation and evacuation efforts for Megi likely saved hundreds of lives. Megi hit Luzon on Monday morning at 3:30 UTC as a Category 5 super typhoon with sustained winds of 165 mph and a central pressure of 914 mb. Severe damage was done to Isabela Province in northern Luzon, and media reports indicate that 200,000 people are homeless.


Figure 2. Visible MODIS satellite image of Megi from NASA's Aqua satellite taken at 1:30am EDT October 20, 2010. At the time, Megi was a Category 4 typhoon with 135 mph winds. Image credit: NASA.

Passage over Luzon Island destroyed Megi's eyewall and inner core region, and the storm compensated by expanding and intensifying the portions of its circulation that were over water. Now that its center is back over water in the South China Sea, Megi has re-developed its inner core and has intensified into a formidable Category 3 typhoon with 125 mph winds. Megi has been able to maintain its larger size, and is now a much larger typhoon than when it hit the Philippines. This is similar to what happened to Hurricane Ike in 2008 when it passed over Cuba, and helped give Ike a very destructive storm surge when it came ashore over Texas. Wind shear is a low 5 - 10 knots over Megi, and the waters of the South China Sea have a very high total heat content to great depth, so Megi should be able to remain a very dangerous major typhoon through Friday. The larger size of Megi means that it will be able to deliver a significant storm surge in excess of ten feet to the coast of China of Friday or Saturday, when the storm is expected to make landfall north of Hong Kong. As the storm approaches the coast on Friday, wind shear is expected to rise to the moderate or high range, and the total heat content of the ocean will drop significantly, so some weakening is to be expected. Still, Megi will probably hit China as a major Category 3 typhoon, or as a strong Category 2, bringing a significant storm surge, high winds, and widespread torrential rains that will likely make this a multi-billion dollar disaster for China. The outer rain bands of Megi are already affecting the coast of China north of Hong Kong, as seen on Hong Kong radar and Taiwan radar.


Figure 3. Still frame of damage to NE Luzon Island from a video posted to YouTube by storm chaser James Reynolds of typhoonfury.com.

Next update
I'll have an update Thursday morning.

Jeff Masters

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Wow, now that is an out on the limb statement.

Quoting RitaEvac:
It was born down there, it will die down there. Not going to Florida.
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Yikes

Member Since: January 30, 2010 Posts: 0 Comments: 3259
It was born down there, it will die down there. Not going to Florida.
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1071. Grothar
90L!!

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Check out MIMIC-TPW

TD19 aint gettin any further north than Yucatan, then it either goes East or West.

North? Not very likely, there is a wall there and if TD19 tries going that way, it will be in a dead zone real soon.

Then 'poof'.

Real disappointing, cause we need the rain real bad here in SWFLA.

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1068. Jax82
SSTs
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90L is the eastern Atlantic disturbance...

Quoting cat5hurricane:

That could be the invest associated with the wave off the African coast...which the NHC is giving 10% chance of development... But I'm not sure.
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Quoting scott39:
I saw on the local news last night, that winds are going to shift from the NW to the SW starting next week.


no thats not what he said at all. he said that currently the sw quad was taking a pounding with wind shear. he is a complete liar.

the weather channel is gone. if you want to trust them, well if your an american you have the right to believe in whatever you want. i just tend to not trust liars, thats all. no offense to you, it was just disgusting to see him lie like that. but to each their own :)

downcasters should love the new weather channel. they will always back up a downcaster lol.
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pdoug: oz is coming to fl,for a ts??,cause its highly unlikely the tampa area gets a hurricane lanfall imo, id offer support,but the way they threw away half the chase team(xtreme wx),for$ $$....i wont offer a thing!!!
Member Since: October 5, 2007 Posts: 20 Comments: 4970
Quoting Chicklit:
What does GFDL say about little richard?





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Quoting Jeff9641:
Just got off the phone with the Melbourne office and they expect the NHC to shift the track east with the new TVCN track. We could be talking about a storm coming here in 5 days.


That's kinda cool...do you have a contact there or do you just call and they'll talk to you?
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and you all thought the Florida landfall idea was nuts.. Maybe Richard will be a CONUS landfall.
Member Since: July 1, 2008 Posts: 13 Comments: 7340
1057. scott39
Quoting Jeff9641:
Just got off the phone with the Melbourne office and they expect the NHC to shift the track east with the new TVCN track. We could be talking about a storm coming here in 5 days.
Are you a Met?
Member Since: June 13, 2009 Posts: 0 Comments: 6740
1056. Grothar
Quoting Jeff9641:


The TVCN will be the new 11am track.


The TVCN is only a concensus model, not really a tracking model. It usually just combines at least 2 or more models and and gives an assumed plot. It changes much more than the regular models.
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1055. HCW
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According to the Google Earths data from the NHC, there is a 90L out there somewhere.... They have the header listed.. just no data yet.




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For those of you keeping score at home, that's 17-9-5, on its way to a very likely 17-10-5, and even an outside chance of 17-10-6....
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guess they are busy updating
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Hi everyone long time lurker here in the Tampa area. Just saw this man named Richard pop up lol. As life would have it, I am suppose to leave Florida next Wednesday to start a new job in Pittsburgh. I am getting a funny feeling that could be delayed a few days. When is Richard predicted to come into the area if all the pieces fall into place?
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How exciting!
Member Since: July 7, 2010 Posts: 0 Comments: 474
1049. scott39
Quoting SweetHomeBamaGOM:
rick knabb is predicting a landfall into the yucatan with complete dissipation shortly thereafter. he also said hard shear was coming in from the sw. i no longer trust the weather channel, nbc, or general electric for that matter.
I saw on the local news last night, that winds are going to shift from the NW to the SW starting next week.
Member Since: June 13, 2009 Posts: 0 Comments: 6740
1048. Grothar
Navy site has it named.

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Quoting SweetHomeBamaGOM:
will megi hit north korea?

Very unlikely. However, Megi's remnants might eventually reach it.
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For those of you wondering about possible Shary in the far eastern Atlantic: while it's not unheard of at this time of year, it is very rare. From the NHC, here are the birthplaces of all TCs that formed over the past 100 years from October 21 to Halloween:

Click for larger image:

Appropriate tropical weather-related image
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Quoting stormwatcherCI:
Published 21st October, 7:06am

Tropical Depression 19 is currently south of the Cayman Islands.

At 5 a.m. the National Hurricane Center in Miami Florida has TD19 near 17.0 N 80.7 W or about 160 miles south-southeast of Grand Cayman, 197 miles south of Cayman Brac.

TD19 is currently moving towards the southeast near 3 mph with maximum sustained winds near 35mph. This system posses no immediate threat to the Cayman Islands; however, rainfall associated with the system will continue to impact the islands over the next day or two. Swells are expected to affect the south and east coast of the Cayman Islands.

The CINWS will continue to monitor the progress of this storm. All interest within the Cayman Islands should continue to monitor the local media for the latest information on this system.

The next bulletin will be issued at 10 a.m. today.

For further information contact: Simon Boxall
what ajoke!!
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rick knabb is predicting a landfall into the yucatan with complete dissipation shortly thereafter. he also said hard shear was coming in from the sw. i no longer trust the weather channel, nbc, or general electric for that matter. not that he could be right about the yucatan landfall, but the sheer attempt at misinformation he just showed. now watch, they will advertise a trip to cozumel 3 minutes later in the commercials.....pathetic.
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Although storm does appear to be getting larger in area not good if it starts to wrap up.
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1038. Grothar
Quoting sammywammybamy:


Are you serious?


No, I kid a lot, but not about storms.

They just posted this a few minutes ago. One of the dynamic models:

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1036. scott39
Quoting cat5hurricane:

Not until days 4 or 5...so a while yet. And only if the mid-level ridge over FL will begin to break down enough in time
Thanks, So its all about the timing?
Member Since: June 13, 2009 Posts: 0 Comments: 6740
Quoting kmanhurricaneman:
http://moe.met.fsu.edu/tcgengifs/ models
Published 21st October, 7:06am

Tropical Depression 19 is currently south of the Cayman Islands.

At 5 a.m. the National Hurricane Center in Miami Florida has TD19 near 17.0 N 80.7 W or about 160 miles south-southeast of Grand Cayman, 197 miles south of Cayman Brac.

TD19 is currently moving towards the southeast near 3 mph with maximum sustained winds near 35mph. This system posses no immediate threat to the Cayman Islands; however, rainfall associated with the system will continue to impact the islands over the next day or two. Swells are expected to affect the south and east coast of the Cayman Islands.

The CINWS will continue to monitor the progress of this storm. All interest within the Cayman Islands should continue to monitor the local media for the latest information on this system.

The next bulletin will be issued at 10 a.m. today.

For further information contact: Simon Boxall
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will megi hit north korea?
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Quoting Jeff9641:


Check post 979 and before you look please look with extreme caution!

http://www.coaps.fsu.edu/~maue/extreme/gfdl/nineteen19l.2010102106_nest3.png


Ouch!! If it wasn't early in the game I would be super worried. But, as happens anytime the models point to something hitting the Tampa Bay area this early - it always shifts away. I'll take that model look now rather than later.
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not much on west side.
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1030. Grothar
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Quoting sammywammybamy:
What are the Newest Models saying?
http://moe.met.fsu.edu/tcgengifs/ models
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1027. Grothar
Quoting sammywammybamy:
What are the Newest Models saying?


Believe it or not,none of the official models are posted yet. They just removed all of them. They must be doing a serious update.
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1026. IKE
Quoting GeoffreyWPB:
AL, 19, 2010102112, , BEST, 0, 165N, 807W, 35, 1006, TS


I saw this...just upgraded....

Information About Tropical Storm Richard

Storm information valid as of: Thursday, October 21, 2010 12:00 Z
Coordinates: 16.5N 80.7W (View Map or View Storm Centered Satellite Image)
Location: 199 miles (320 km) to the SSE (167°) from George Town, Cayman Islands (GBR)
Distance Calculator: How far away is this storm from me?
Pressure (MSLP): 1006 mb (29.71 inHg | 1006 hPa)
Sustained wind speed (1 min. avg.): 35 knots (40 mph | 18 m/s)
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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.