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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789. amd
post 753 shows why the nhc waited so long to name it. In the last couple of frames of that loop, 90L finally breaks away from the front, and as soon as it does, the eye like feature forms.

Hence soon to be tropical storm Grace
Member Since: August 29, 2005 Posts: 0 Comments: 1024
Quoting Weather456:


It is, my bad on that, I should use a calculator next time.


if you want to be technical, it is 63.3 mph :P
Member Since: June 28, 2006 Posts: 24 Comments: 8201
Quoting Weather456:
The CATL should be orange, showers are now becoming symmetric.



456 Is this comming our way in the NE caribbean? if Develops?
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Quoting Magicchaos:


I thought 55kts converted to 65mph?


It is, my bad on that, I should use a calculator next time.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
Quoting Tazmanian:
the next thing we no is that the nhc will start name fish or brids from the sky or crows


When Henri forms...what comes afer eating crow?...:)
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Quoting Weather456:
Advisories will be out shortly

60 mph

smallest hurricane i've ever seen
Member Since: July 15, 2006 Posts: 169 Comments: 53296
Quoting Weather456:


This will get you up to speed



Hola,

you might want to read this;

Also someone else from Spain sent me this image and was wondering why the NHC failed to mentioned it

This 90L Today, Sunday 4 October


""[The National Hurricane center] seems to be naming a lot more than they used to. This year, I would put four storms in the very questionable category, and maybe even six. In the past, we would have waited to see if another observation supported naming the system. We would have been a little more conservative."

Neil Frank, National Hurricane Center Director, 1974-1987.

1. Aren't occluded lows a characteristic of mid-latitude cyclones and don't subtropical cyclones have characteristics of both tropical and mid-latitude systems, which has fronts.

2. Aren't occluded lows the sign of a decaying mid-latitude system.

3. Does the satellite presentation support this feature being tied to a front.

4. Is there a temperature contrast along 90L, the last time I check occluded lows have uniformed temperatures.

4. Subtropical cyclones have some sort of frontal feature to their NW.

5. QS showed the strongest winds near a very well define LLCC.


Systems near Greenland as I said before have warm-cores but they are not subtropical or tropical becuz they have more non-tropical features than tropical. For one, they are baroclinic.

You cannot use 23C to define a line, there is no line when it comes to classifying systems because not all systems are perfect. For instant, a tropical depression does not have specific winds of 30, 33, 36 mph, its either 25, 30 or 35 mph. And to say SSTs were too cold when it was 22C is an exaggeration, what is the biggest difference between 22 and 23C when the system is producing convection as if it was over 24C?

So how come Vince was classified over 23C, isn't the threshold for tropical systems 26C?

I am seeing comments about water is too cold and such and that really the only argument against 90L-ex. Now tell me, if the waters are too cold why is the system produce convection? You know what those cirrus clouds indicate? Those cirrus clouds indicate air is hitting the tropopause and has no where to go but outward (outflow). Mid-latitude systems don't have convective clouds that extend that far up that's why thunderstorm frequency drops dramatically in the high lats.

Another thing, the lapse rate, if the SSTs are that cool then the air directly above the sea surface should be cooler than the air aloft (temperating rising with height is a stable situation). The only way this system could produce such organize convection on each frame for 6 hrs, is if the lapse rate was decreasing with height (unstable situation), and in order for that to happen SSTs have to be warmer than the air aloft.

Some of my co-workers who have much more experienced than I am are dumb-founded as to why the NHC has not mentioned this system today. Something is not adding up and the last time I check I haven't had any mental problems, lol. This is utterly whack!




ok thanks
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Quoting Weather456:
Advisories will be out shortly

60 mph



I thought 55kts converted to 65mph?
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Quoting Tazmanian:
the next thing we no is that the nhc will start name fish or brids from the sky or crows


This will get you up to speed

Quoting Cazatormentas:
Evening all from Spain :)

Does anyone know what area consider cyclone phase diagrams? I'm sure the extratropical low of Azores has developed a well separated tropical engine perturbation... Despite its origin and despite of those cyclone phase diagrams.

Thanks! :D


Hola,

you might want to read this;

Also someone else from Spain sent me this image and was wondering why the NHC failed to mentioned it

This 90L Today, Sunday 4 October


""[The National Hurricane center] seems to be naming a lot more than they used to. This year, I would put four storms in the very questionable category, and maybe even six. In the past, we would have waited to see if another observation supported naming the system. We would have been a little more conservative."

Neil Frank, National Hurricane Center Director, 1974-1987.

1. Aren't occluded lows a characteristic of mid-latitude cyclones and don't subtropical cyclones have characteristics of both tropical and mid-latitude systems, which has fronts.

2. Aren't occluded lows the sign of a decaying mid-latitude system.

3. Does the satellite presentation support this feature being tied to a front.

4. Is there a temperature contrast along 90L, the last time I check occluded lows have uniformed temperatures.

4. Subtropical cyclones have some sort of frontal feature to their NW.

5. QS showed the strongest winds near a very well define LLCC.


Systems near Greenland as I said before have warm-cores but they are not subtropical or tropical becuz they have more non-tropical features than tropical. For one, they are baroclinic.

You cannot use 23C to define a line, there is no line when it comes to classifying systems because not all systems are perfect. For instant, a tropical depression does not have specific winds of 30, 33, 36 mph, its either 25, 30 or 35 mph. And to say SSTs were too cold when it was 22C is an exaggeration, what is the biggest difference between 22 and 23C when the system is producing convection as if it was over 24C?

So how come Vince was classified over 23C, isn't the threshold for tropical systems 26C?

I am seeing comments about water is too cold and such and that really the only argument against 90L-ex. Now tell me, if the waters are too cold why is the system produce convection? You know what those cirrus clouds indicate? Those cirrus clouds indicate air is hitting the tropopause and has no where to go but outward (outflow). Mid-latitude systems don't have convective clouds that extend that far up that's why thunderstorm frequency drops dramatically in the high lats.

Another thing, the lapse rate, if the SSTs are that cool then the air directly above the sea surface should be cooler than the air aloft (temperating rising with height is a stable situation). The only way this system could produce such organize convection on each frame for 6 hrs, is if the lapse rate was decreasing with height (unstable situation), and in order for that to happen SSTs have to be warmer than the air aloft.

Some of my co-workers who have much more experienced than I am are dumb-founded as to why the NHC has not mentioned this system today. Something is not adding up and the last time I check I haven't had any mental problems, lol. This is utterly whack!

Member Since: July 24, 2005 Posts: 407 Comments: 19076
Quoting Weather456:


Hey CCH! Another one for the books.


Definitely. Seems like our arguments have proven true with yet another system. About time this became a tropical cyclone.
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Pretty much the sister of Vince (2005).
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776. xcool



Member Since: September 26, 2009 Posts: 2 Comments: 15626
Quoting kmanislander:


Took a look but did not see anything that jumped out at me. What is it that catches your attention ?
On the four panel model, the bottom right map shows two areas of low pressure moving west toward the Western Caribbean Sea.
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Also shear has been decreasing somewhat in the Atlantic, maybe this wave might make it to the islands in one piece. Definitely should watch the Western Carribean next week.
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the next thing we no is that the nhc will start name fish or brids from the sky or crows
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Advisories will be out shortly

60 mph

Member Since: July 24, 2005 Posts: 407 Comments: 19076
673

WHXX01 KWBC 050212

CHGHUR

TROPICAL CYCLONE GUIDANCE MESSAGE

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL

0212 UTC MON OCT 5 2009



DISCLAIMER...NUMERICAL MODELS ARE SUBJECT TO LARGE ERRORS.

PLEASE REFER TO NHC OFFICIAL FORECASTS FOR TROPICAL CYCLONE

AND SUBTROPICAL CYCLONE INFORMATION.



ATLANTIC OBJECTIVE AIDS FOR



TROPICAL CYCLONE GRACE (AL092009) 20091005 0000 UTC



...00 HRS... ...12 HRS... ...24 HRS. .. ...36 HRS...

091005 0000 091005 1200 091006 0000 091006 1200



LAT LON LAT LON LAT LON LAT LON

BAMS 40.2N 21.3W 42.8N 18.1W 45.8N 15.4W 48.0N 13.3W

BAMD 40.2N 21.3W 43.6N 17.6W 47.2N 16.0W 49.6N 13.9W

BAMM 40.2N 21.3W 43.3N 17.8W 46.6N 15.8W 48.8N 13.8W

LBAR 40.2N 21.3W 43.1N 16.0W 46.8N 10.8W 50.3N 2.8W

SHIP 55KTS 60KTS 63KTS 63KTS

DSHP 55KTS 60KTS 63KTS 63KTS



...48 HRS... ...72 HRS... ...96 HRS. .. ..120 HRS...

091007 0000 091008 0000 091009 0000 091010 0000



LAT LON LAT LON LAT LON LAT LON

BAMS 49.1N 11.3W 49.5N 8.4W 48.4N 3.1W 49.2N 4.0E

BAMD 51.6N 9.1W 55.5N 9.8E 56.9N 36.2E 58.2N 62.7E

BAMM 50.3N 11.0W 52.9N 3.2W 54.4N 10.7E 54.8N 26.0E

LBAR 53.2N 8.8E .0N .0W .0N .0W .0N .0W

SHIP 66KTS 64KTS 58KTS 48KTS

DSHP 66KTS 51KTS 30KTS 30KTS



...INITIAL CONDITIONS...

LATCUR = 40.2N LONCUR = 21.3W DIRCUR = 75DEG SPDCUR = 22KT

LATM12 = 38.3N LONM12 = 26.8W DIRM12 = 87DEG SPDM12 = 22KT

LATM24 = 39.1N LONM24 = 31.0W

WNDCUR = 55KT RMAXWD = 15NM WNDM12 = 45KT

CENPRS = 990MB OUTPRS = 1000MB OUTRAD = 175NM SDEPTH = D

RD34NE = 45NM RD34SE = 45NM RD34SW = 40NM RD34NW = 20NM



$$

NNNN


Member Since: July 15, 2006 Posts: 169 Comments: 53296
770. ackee
grace has an eye? is it nearing hurricane strength
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Grace already looks like a Hurricane lol, reminds me of Hurricane Grace in 1991.
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Quoting Tazmanian:
this is no name storm it dont even look like a name storm its way too far N


TROPICAL CYCLONE GRACE (AL092009) 20091005 0000 UTC

Link
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Quoting hydrus:
KMAN-If you have time, check out the Canadian gem model, very interesting.


Took a look but did not see anything that jumped out at me. What is it that catches your attention ?
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Quoting Tazmanian:
this is no name storm it dont even look like a name storm its way too far N


it is named though, it is very well developed and should probably have been named awhile ago, imo
Member Since: June 28, 2006 Posts: 24 Comments: 8201
Oh Tacoman!!!! Where are you??? :P

Hmm got some special taco crow for ya buddy! :/
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Quoting Tazmanian:
this is no name storm it dont even look like a name storm its way too far N


11pm is definite, already renumbered
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Quoting Weather456:


This is just surreal, LOL. Grace is here.
A STAR IS BORNED
Member Since: July 15, 2006 Posts: 169 Comments: 53296
Quoting cchsweatherman:


Not surprising considering the continued organization and increase in shower and thunderstorm action.


Hey CCH! Another one for the books.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
Quoting tornadodude:
we now have Grace, where is tacoman now???
Eating crow tacos.
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Quoting nrtiwlnvragn:
10/05/2009 02:08AM 1,818 invest_RENUMBER_al902009_al092009.ren


Not surprising considering the continued organization and increase in shower and thunderstorm action.
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Quoting 1900hurricane:

Link? Please and thank you! :)


Link
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this is no name storm it dont even look like a name storm its way too far N
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See 456...the NHC does come through in the pinch!
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Quoting kmanislander:


I think orange sometime between 2 and 5 a.m.


same here, But I will go with 8, mine you 2am is not out of the question but being pessimistic.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
755. ackee
any one has the link to grace is it me or has GRACE always been a fish storm each time they use that name ?
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Quoting GeoffreyWPB:


Bet they ruins Tamaleman's...or whatever his name is...day:)


was his name snackwrap?
Member Since: June 28, 2006 Posts: 24 Comments: 8201


AOI/91/XL
MARK
12.8N/39.1W



TS/09/G
MARK
40.8N/19.1W
Member Since: July 15, 2006 Posts: 169 Comments: 53296
Quoting presslord:
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



Many angels still walk the earth. God is good.
Member Since: October 9, 2008 Posts: 0 Comments: 8278
Quoting Weather456:


we already got Grace


Bet they ruins Tamaleman's...or whatever his name is...day:)
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Quoting Weather456:
The CATL should be orange, showers are now becoming symmetric.



I think orange sometime between 2 and 5 a.m.
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Quoting nrtiwlnvragn:
GRACE AL L 09 2009 TS


This is just surreal, LOL. Grace is here.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
we now have Grace, where is tacoman now???
Member Since: June 28, 2006 Posts: 24 Comments: 8201
GRACE AL L 09 2009 TS
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and i was starting to like 6 name storms
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Quoting Magicchaos:
invest_RENUMBER_al902009_al092009.ren

Grace is born.

Link? Please and thank you! :)
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Quoting hurristat:


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


LOL. A Eureka moment eh ?
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Quoting ackee:
any one think we see Grace by tonight ? see TW may be the intresting thing to watch so far this seasons the NE carrb has been impact by two system this may very well be the thrid one


we already got Grace
Member Since: July 24, 2005 Posts: 407 Comments: 19076
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741. ackee
any one think we see Grace by tonight ? see TW may be the intresting thing to watch so far this seasons the NE carrb has been impact by two system this may very well be the thrid one
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Quoting Magicchaos:
invest_RENUMBER_al902009_al092009.ren

Grace is born.


WOW, LOL I'm estatic!
Member Since: July 24, 2005 Posts: 407 Comments: 19076
10/05/2009 02:08AM 1,818 invest_RENUMBER_al902009_al092009.ren
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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.