An Atlantic tropical wave worth watching

By: Dr. Jeff Masters , 2:46 PM GMT on October 04, 2009

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A large tropical wave near 9N 40W, midway between Africa and the Lesser Antilles Islands, is generating a considerable amount of heavy thunderstorm activity as it moves west to west-northwest at 15 mph. The wave is under about 10 - 15 knots of wind shear, and this morning's QuikSCAT pass showed a large and disorganized region of converging winds in the region, with top winds of 25 mph. There is very little dry air in the vicinity, and conditions appear favorable for some slow development of this wave. None of the computer models develop the wave, but they do show relatively low wind shear along the wave's path for the next five days. The wave should reach the Lesser Antilles Islands by Wednesday.


Figure 1. The large tropical wave in the middle Atlantic.

In the Philippines, Tropical Storm Parma continues to linger offshore the northern tip of the Philippines' Luzon Island, bringing heavy rain. The storm has been blamed for the deaths of 17 people in the Philippines, but has not not had the devastating impact that was earlier feared. Parma's heaviest rains will stay offshore of the Philippines today (Figure 2).


Figure 2. Forecast rain amounts for Parma for the 24-hour period ending at 06 UTC October 5 (2am EDT Monday). This forecast is based on satellite measurements of Parma's current rainfall rate, plus a projection of the storm's path. Four to eight inches of rain (yellow colors) is expected along the extreme northwest tip of Luzon Island. Image credit: NOAA Satellite Services Division.

Super Typhoon Melor hits Cat 5 strength
Super Typhoon Melor has become the second Category 5 tropical cyclone of the year. Melor is expected to recurve to the north pass just south of the coast of Japan later this week.

Jeff Masters

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10/05/2009 02:08AM 1,818 invest_RENUMBER_al902009_al092009.ren
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Quoting kmanislander:


My lack of interest in the Azores system has nothing to do with the prognosis but everything to do with proximity to the NW Caribbean.


Hold on...lessee... your username is Kmanislander....kman...kman... CAYMAN! okay. Cayman Islander. Ok. *gets an atlas* OH! I GET IT!
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Quoting kmanislander:


True enough. All you need is 2 days of relatively low shear to open the door to trouble. Paloma came up from the South of us in less than 48 hours.



yes but all so true is that. that name storm was not in a EL Nino year so see a cat 4 like that storm this year is vary small ch right now
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For those that are interested in what's happening with Invest 90-L this evening in the NE Atlantic, I found this eye-opening paper on Hurricane Vince:

Kwan-yin Kong. Understanding the Genesis of Hurricane Vince Through the Surface Pressure Tendency Equation . City College of New York.

This paper suggests a new paradigm in the thinking of how hurricanes form and develop.

Here is the current way we think: Deep bursts of convection over the center release latent heat, creating a strengthening vertical warm core over the center. A warmed column of air leads to low surface pressure (cyclonic spin at the surface) and high upper air pressure (upper anticyclone with cirrus outflow).

Here is the way this paper alters the thinking: Deep bursts of convection causes the central column of air to have a moist super-adiabatic lapse rate, thus resulting in a statically unstable atmosphere. The statically unstable atmosphere at the core of a hurricane causes air parcels to rise, causing low surface pressure and higher upper air pressure.

Now, this may explain why you can have a hurricane below 26 deg C water. All you need is to have a significantly unstable lapse rate to cause surface pressure falls. Over cooler sea surfaces, a cold core upper low over a deeply-occluded surface cyclone can allow for a super-unstable lapse rate due to the temp difference btn. the sea surface and cold core upper low.

I may have a post on this on my blog later this week (talk about skew-T diagrams, etc., so that this is understandable).
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invest_RENUMBER_al902009_al092009.ren

Grace is born.
Member Since: April 3, 2009 Posts: 107 Comments: 382
Quoting Tazmanian:



if you have the right wind shear that is


True enough. All you need is 2 days of relatively low shear to open the door to trouble. Paloma came up from the South of us in less than 48 hours.
Member Since: August 19, 2006 Posts: 0 Comments: 15671
The CATL should be orange, showers are now becoming symmetric.

Member Since: July 24, 2005 Posts: 407 Comments: 19076
Quoting kmanislander:


I think the final hoorah will be a system coming up from the Southern Caribbean and potentially becoming a Cat 4 or worse late in the season. The water temps and TCHP are off the scale in the NW Caribbean and all we need is a cold front to stall out late Oct or early Nov and develop a tail end low East of Nicaragua to cause significant problems.

That is my real concern for the reat of the season.
KMAN-If you have time, check out the Canadian gem model, very interesting.
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Quoting Tazmanian:



if you have the right wind shear that is


you called for no more storms this season right?
Member Since: June 28, 2006 Posts: 24 Comments: 8185
from: Krissy Baxter's aunt Jody:


Yesterday morning when Krissy, Bryan, the kids and Helen woke up, everyone was excited. They knew that people had given things and had some idea there was going to be a lot of stuff, but when the truck filled with gifts from the hearts of people they don't know and a man named John who saw a need and filled it arrived and the door was lifted, they were floored.
Everyone now has a bed to sleep on, an area rug that was sent, fits perfectly, the only bedroom that didn't have carpet.
Pots and pans, Corning ware, Tupperware, plastic ware, all with lids Krissy likes to point out. Toilet paper, paper plates, towels, wash clothes, sheets, pillow cases, comforters, and pillows. Alcohol (not the drinking kind), lotion, perfume, cologne, laundry detergent, bars of soap, dish detergent, vacuum, broom, mop and dustpan.
Clothes, shoes, underwear, socks, jackets, pajama's and robes.
Nothing was overlooked.
So far, there hasn't been anything that they received yesterday that was not needed.
I wished that I would have had the equipment, time and a way to have been there. As I watched the web cam I thought about what a testimony it would have been. To have taken all of those images and then edited it to where I would have started at the old house, to show the destruction and devastation. The entire ceiling caved in, the refrigerator which had fallen over and furniture that was covered with the ceiling, insulation, and muck. It looked like a water bomb had gone off. Krissy, who when asked to come into view to describe what had happened started off good but then broke down. To show her and Bryan going through and picking up a few salvageable things. Then show the new house with nothing in it but some inflatable mattresses, no furniture and bare. And then show the truck arriving with a man we only know as John. The opening of the door to the truck filled with everything that would now make this new house a home.
Krissy and Bryan have been opening boxes since yesterday. They put the beds up first and then put the furniture where it will go. A kitchen table and chairs, living room furniture, televisions, DVD player, and so many other things to numerous to mention at this time. Cabinets that are now filled with dishes, pots and pans and so many things that it is mind boggling. As the boxes are opened the things are being put away, and as the boxes are emptied it is filling this home with all the love these things were sent with.
To all of you who had anything to do with this act of love, I want you to know this, tomorrow will be two weeks since the flooding took everything they owned and because of all of you, it was a blink in time when they didn't know what they were going to do. Now, what can I say other than wow, we have an awesome God, who can make a way when you think there is no way.
I kept thinking that I should go and look at the Goodwill for an Elmo for Aiden. I kept thinking it until about 5:30 when I had about 30 minutes left till they closed. So off I went and when I walked through the door I went straight to him sitting on the shelf waiting for me. Then I went and found an Elmo DVD and a smaller Elmo. I also found 4 Elmo wash cloths. Krissy said they have four more boxes and they'll be done. She and Tori took care of the kitchen stuff while Bryan and the boys got the other stuff in place.
Krissy said there are four more boxes to go through tomorrow and she will take pictures and send them in an e-mail to me to share with you all.
For those of you that keep a prayer journal go on and marked this prayer answered.
Thanks again
Jody



Member Since: August 13, 2007 Posts: 0 Comments: 10458
Quoting mcswains:


I honestly do not know. I would assume well, but that is a complete guess based on how well Okinawa has faired in the past. That being said, Okinawa is pretty far to the south of mainland and honestly while still Japan, it is a completely different culture. I'm not sure how the mainland Japanese construct buildings etc.


Thanks. I'm thinking they will probably be reasonably safe in a hotel with a category 1 hit, but it would sure be a bumpy night.
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Quoting WeatherStudent:
G'evening Taz!



hi
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Quoting kmanislander:


I think the final hoorah will be a system coming up from the Southern Caribbean and potentially becoming a Cat 4 or worse late in the season. The water temps and TCHP are off the scale in the NW Caribbean and all we need is a cold front to stall out late Oct or early Nov and develop a tail end low East of Nicaragua to cause significant problems.

That is my real concern for the reat of the season.



if you have the right wind shear that is
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Quoting Tazmanian:



i been off the blogs most of the weekend


fill me in lol



and all so where watching this


000
FXUS66 KMTR 050037
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA CA
535 PM PDT SUN OCT 4 2009


ALTHOUGH IT IS A LONG WAY OFF...NEXT WEEK IS STARTING TO LOOK VERY
INTERESTING AS THE GFS AND ECMWF BRING MOISTURE FROM TYPHOON MELOR
(CURRENTLY AT 17.9/137.7) TOWARD OUR AREA AND POINTS TO THE NORTH.
ALTHOUGH SOME OF THE GUIDANCE SHOWS IMPRESSIVE RAINFALL TOTALS FOR
NAPA/SONOMA...THE ENSEMBLES DO SHOW A LARGE SPREAD FOR NEXT WEEK.
THIS IS DEFINITELY IN A WAIT-AND-SEE MODE.
90L at red. AOI CATL yellow.
Member Since: October 9, 2008 Posts: 0 Comments: 8242
Quoting kmanislander:


I think the final hoorah will be a system coming up from the Southern Caribbean and potentially becoming a Cat 4 or worse late in the season. The water temps and TCHP are off the scale in the NW Caribbean and all we need is a cold front to stall out late Oct or early Nov and develop a tail end low East of Nicaragua to cause significant problems.

That is my real concern for the reat of the season.
Visions of Paloma.
Member Since: October 9, 2008 Posts: 0 Comments: 8242
722. xcool



Member Since: September 26, 2009 Posts: 2 Comments: 15603
Quoting stormwatcherCI:
Hey Taz. You been busy or what. Haven't seen you on at all today.



i been off the blogs most of the weekend


fill me in lol



and all so where watching this


000
FXUS66 KMTR 050037
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA CA
535 PM PDT SUN OCT 4 2009


ALTHOUGH IT IS A LONG WAY OFF...NEXT WEEK IS STARTING TO LOOK VERY
INTERESTING AS THE GFS AND ECMWF BRING MOISTURE FROM TYPHOON MELOR
(CURRENTLY AT 17.9/137.7) TOWARD OUR AREA AND POINTS TO THE NORTH.
ALTHOUGH SOME OF THE GUIDANCE SHOWS IMPRESSIVE RAINFALL TOTALS FOR
NAPA/SONOMA...THE ENSEMBLES DO SHOW A LARGE SPREAD FOR NEXT WEEK.
THIS IS DEFINITELY IN A WAIT-AND-SEE MODE.
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Quoting WeatherStudent:
Gotcha Kman. But might this potentially be Mother Nature' final significant hoorah of the season before we kiss 2009 goodbye? Stay tune and find out, I guess, huh? LOL.


I think the final hoorah will be a system coming up from the Southern Caribbean and potentially becoming a Cat 4 or worse late in the season. The water temps and TCHP are off the scale in the NW Caribbean and all we need is a cold front to stall out late Oct or early Nov and develop a tail end low East of Nicaragua to cause significant problems.

That is my real concern for the reat of the season.
Member Since: August 19, 2006 Posts: 0 Comments: 15671
Quoting Tazmanian:
guys we dont need to post 100s of TROPICAL WEATHER OUTLOOK



i find that vary annyoing
Hey Taz. You been busy or what. Haven't seen you on at all today.
Member Since: October 9, 2008 Posts: 0 Comments: 8242
Quoting JamesSA:

How well does Tokyo handle typhoons? I have friends arriving there on Tuesday to perform in concerts, and I am concerned about them.


I honestly do not know. I would assume well, but that is a complete guess based on how well Okinawa has faired in the past. That being said, Okinawa is pretty far to the south of mainland and honestly while still Japan, it is a completely different culture. I'm not sure how the mainland Japanese construct buildings etc.
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guys we dont need to post 100s of TROPICAL WEATHER OUTLOOK



i find that vary annyoing
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Quoting mcswains:
I am originally from Alabama and when we get storms, the east side of the storm is usually worse. Is that the same deal with the storms now that I live in Okinawa? I have read that typhoons and hurricanes are the same thing- just different names.
it is south of the equator that everything is reversed.
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715. xcool
hurricaneseason2006 poof
Member Since: September 26, 2009 Posts: 2 Comments: 15603
Quoting hurricaneseason2006:


Just a few hours ago you did not expected this to develop. How ironic.
Go away troll.
Member Since: October 9, 2008 Posts: 0 Comments: 8242
712. xcool


Member Since: September 26, 2009 Posts: 2 Comments: 15603
Hey everyone, Im just gonna pop in briefly since it seems like things are warming up in the atlantic alittle. Question: With 90L what do you call that "eye" thing. I mean, its not a real "hurricane eye" (at least not yet anyway) but do you call it an eye? or something else?
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Quoting mcswains:


Very true. Seems to be a little different here than in the States though. The houses are all solid concrete and no real threat of flooding for most of the island. The Okinawans are just used to the weather threats and build for it. That being said we are on an island and it is a Cat V Super Typhoon we are talking about so nothing should be taken lightly.

How well does Tokyo handle typhoons? I have friends arriving there on Tuesday to perform in concerts later in the week, and I am concerned about them.
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If that high stays parked there it could penetrate quite some distance W before turning.

Member Since: August 19, 2006 Posts: 0 Comments: 15671
May start to ramp up once it gets past 50W:

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My track is west to wnw through 3 days, turning a bit more north under the influence of passing trough to the north. This will likely not pick up the system but could influence the ridge currently steering it. The exact timing of these two features will determine how far south/north it gets. My current thinking is between the central lesser Antilles and just north of the Leewards, thus the NE Caribbean, PR, DR and Haiti should monitor this system in the near term.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
Quoting WeatherStudent:
Evening KMan. Hope all is well. So sir, do you forsee any level of concern in reference to this latest tropical critter>


Good evening to you. Not concerned at the moment. It is just an area of interest.

However, conditions seem to favour additional development. It is still a long way out.
Member Since: August 19, 2006 Posts: 0 Comments: 15671
Quoting Drakoen:


I would considered upper level winds forecast in the Caribbean to be extremely favorable for development.
Another encouraging prognosis. HaHa. Not exactly what I wanted to hear.
Member Since: October 9, 2008 Posts: 0 Comments: 8242
Looks like we may have another monster on our hands before long.

Not good.
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Quoting JamesSA:

I am happy to hear that people are freaking out over it... What is worse is when they pay no attention! At least they will prepare.


Very true. Seems to be a little different here than in the States though. The houses are all solid concrete and no real threat of flooding for most of the island. The Okinawans are just used to the weather threats and build for it. That being said we are on an island and it is a Cat V Super Typhoon we are talking about so nothing should be taken lightly.
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Quoting Weather456:


That is correct
Thanks. Maybe I will learn something after all from you folks who don't know anything. j/k LOL
Member Since: October 9, 2008 Posts: 0 Comments: 8242
Quoting WeatherStudent:
Drak, if this does manage to get into the Carib., what type of trayectory might it take from that point on forth?



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Quoting stormwatcherCI:
I don't really understand the charts but I take it you are showing Kman that in 84 hrs shear in the Caribbean will not be high at all. Please correct me if I am wrong because it looks like (to my untrained eye) that it will be more conducive.


I would considered upper level winds forecast in the Caribbean to be extremely favorable for development.
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Repeat Post
Member Since: September 10, 2007 Posts: 0 Comments: 10587
Quoting hurristat:


The NHC has given the CATL wave a >30% chance of developing and the Azores system a <50% chance- they say they may even initiate advisories "sometime tonight."


My lack of interest in the Azores system has nothing to do with the prognosis but everything to do with proximity to the NW Caribbean.
Member Since: August 19, 2006 Posts: 0 Comments: 15671
Tropical Update from today
Member Since: July 24, 2005 Posts: 407 Comments: 19076
Quoting amd:


the eye is as clean now as it has ever been with Melor. However, it looks like convection is eroding slightly in the western eye wall.

Water vapor loop of Melor

Yeah, I see that, although I'm not sure if it is due to the ingestion of dry air or if it is merely a convective inconsistency due the the EWRC. Whatever it is though, it will show itself soon as Melor either weakens or strengthens.
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Quoting stormwatcherCI:
I don't really understand the charts but I take it you are showing Kman that in 84 hrs shear in the Caribbean will not be high at all. Please correct me if I am wrong because it looks like (to my untrained eye) that it will be more conducive.


That is correct
Member Since: July 24, 2005 Posts: 407 Comments: 19076
Quoting mcswains:
Thanks 1900. Husband and I are stationed in Oki and all the bases are freaking out over this one. I prefer to gather my own information before I freak out! lol, just kidding.

I am happy to hear that people are freaking out over it... What is worse is when they pay no attention! At least they will prepare.
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Quoting kmanislander:


Not really interested in the Azores system but think the CATL wave has a better than 50% chance of being classified as a TD within 24 hrs.


The NHC has given the CATL wave a >30% chance of developing and the Azores system a <50% chance- they say they may even initiate advisories "sometime tonight."
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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.