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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639. xcool
Member Since: Posts: Comments:
Quoting Weather456:
YES! I'm not crazy!
Far from it. That's why you need to forget about what some rabblerousers are saying and go with what you know.
Member Since: October 9, 2008 Posts: 0 Comments: 8279
Expect advisories at 11pm on Invest 90L as Tropical Storm Grace
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636. xcool
oh wow at red
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635. amd
Quoting Weather456:
YES! I'm not crazy!


good call w456. I don't think I have ever seen a system named while ene of the azores, and unless something dramatically changes, Grace will be named.

I'm interested in the 11 pm discussion on possibly future Grace.
Member Since: Posts: Comments:
90L at red alert now.
Member Since: October 9, 2008 Posts: 0 Comments: 8279
Quoting stormwatcherCI:
Acknowledgement at last. I wonder why only yellow ?


Its at >50%, they just updated the map to red.
Member Since: September 23, 2005 Posts: 14 Comments: 10922
YES! I'm not crazy!
Member Since: July 24, 2005 Posts: 407 Comments: 19076
Melor is baaad.

examiner.com
Member Since: July 11, 2006 Posts: 14 Comments: 11190
Quoting stormwatcherCI:
So much sadness in the world and so little we can do.


This group is onsite already... and they have an easy way to donate online. Even if its only $5, its better then nothing.

Caritas Australia

Member Since: Posts: Comments:
629. xcool



Member Since: Posts: Comments:
Quoting nrtiwlnvragn:
000
ABNT20 KNHC 050111
TWOAT
SPECIAL TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
905 PM EDT SUN OCT 4 2009

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

SPECIAL OUTLOOK ISSUED TO UPDATE DISCUSSION OF LOW NORTHEAST OF THE
AZORES

SHOWER ACTIVITY ASSOCIATED WITH THE AREA OF LOW PRESSURE LOCATED
ABOUT 300 MILES EAST-NORTHEAST OF THE AZORES ISLANDS HAS CONTINUED
TO BECOME BETTER ORGANIZED AND THE SYSTEM APPEARS TO BE ACQUIRING
TROPICAL CHARACTERISTICS. IF THIS TREND CONTINUES OVER THE NEXT
HOUR OR TWO...ADVISORIES ON A TROPICAL STORM WILL BE INITIATED
LATER THIS EVENING.
THERE IS A HIGH CHANCE...GREATER THAN 50
PERCENT...OF THIS SYSTEM BECOMING A TROPICAL CYCLONE DURING THE
NEXT FEW HOURS.

A TROPICAL WAVE LOCATED ABOUT 1200 MILES EAST OF THE WINDWARD
ISLANDS IS PRODUCING A LARGE AREA OF DISORGANIZED SHOWERS AND
THUNDERSTORMS. SOME SLOW DEVELOPMENT OF THIS SYSTEM IS POSSIBLE
OVER THE NEXT COUPLE OF DAYS AS IT MOVES WESTWARD AT 15 TO 20 MPH.
THERE IS A LOW CHANCE...LESS THAN 30 PERCENT...OF THIS SYSTEM
BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.
Acknowledgement at last. I wonder why only yellow ?
Member Since: October 9, 2008 Posts: 0 Comments: 8279
If they start advisories, It will start at 65 mph according to the ATCF.

AL, 90, 2009100500, , BEST, 0, 402N, 213W, 55, 990, EX,
Member Since: Posts: Comments:
Quoting Chicklit:


Yeah, but it helps to acknowledge it, even when there is no getting around the facts.

I know. Even in the Cayman Islands after 9/11 several agencies were taking donations to assist in whatever way they could.
Member Since: October 9, 2008 Posts: 0 Comments: 8279
000
ABNT20 KNHC 050111
TWOAT
SPECIAL TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
905 PM EDT SUN OCT 4 2009

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

SPECIAL OUTLOOK ISSUED TO UPDATE DISCUSSION OF LOW NORTHEAST OF THE
AZORES

SHOWER ACTIVITY ASSOCIATED WITH THE AREA OF LOW PRESSURE LOCATED
ABOUT 300 MILES EAST-NORTHEAST OF THE AZORES ISLANDS HAS CONTINUED
TO BECOME BETTER ORGANIZED AND THE SYSTEM APPEARS TO BE ACQUIRING
TROPICAL CHARACTERISTICS. IF THIS TREND CONTINUES OVER THE NEXT
HOUR OR TWO...ADVISORIES ON A TROPICAL STORM WILL BE INITIATED
LATER THIS EVENING.
THERE IS A HIGH CHANCE...GREATER THAN 50
PERCENT...OF THIS SYSTEM BECOMING A TROPICAL CYCLONE DURING THE
NEXT FEW HOURS.

A TROPICAL WAVE LOCATED ABOUT 1200 MILES EAST OF THE WINDWARD
ISLANDS IS PRODUCING A LARGE AREA OF DISORGANIZED SHOWERS AND
THUNDERSTORMS. SOME SLOW DEVELOPMENT OF THIS SYSTEM IS POSSIBLE
OVER THE NEXT COUPLE OF DAYS AS IT MOVES WESTWARD AT 15 TO 20 MPH.
THERE IS A LOW CHANCE...LESS THAN 30 PERCENT...OF THIS SYSTEM
BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.
Member Since: September 23, 2005 Posts: 14 Comments: 10922
Quoting stormwatcherCI:
So much sadness in the world and so little we can do.


Yeah, but it helps to acknowledge it, even when there is no getting around the facts.

Member Since: July 11, 2006 Posts: 14 Comments: 11190
Quoting beell:
LOL tf,
not a total ignoration then!


Far from it - LOL
Member Since: Posts: Comments:
Quoting Orcasystems:


The models say it will... that should give you a smidge better then a 50/50 chance... like maybe 60/40.

That being said... Parma hung a left instead of a right...


Yeah, I just saw that. We got alot of rain yesterday (maybe Parma related?). Melor seems to be the one to watch... Hopefully it will turn although it is still likely we will get some weather from it.
Member Since: Posts: Comments:
Quoting mcswains:
Posting from Okinawa Japan and watching Melor. Everyone think this thing is actually going to turn before it hits us here?


The models say it will... that should give you a smidge better then a 50/50 chance... like maybe 60/40.

That being said... Parma hung a left instead of a right...
Member Since: Posts: Comments:
Quoting nrtiwlnvragn:
They just bumped AL90 to 55 kt.

AL 90 2009100500 BEST 0 402N 213W 55 990 EX


Maybe the NHC will name is an "Azoresacane" or "Shrimpacane! Just kidding..

It's the most compact and well organized lil' extra-tropical system I've ever seen.
Member Since: August 25, 2009 Posts: 20 Comments: 6785
Quoting mcswains:
Posting from Okinawa Japan and watching Melor. Everyone think this thing is actually going to turn before it hits us here?


It is forecast to turn, and if it does not turn, it is forecast to weaken somewhat also. but, since they forecast it to turn, and if it does not, we cant really take the intensity forecast seriously either :P
Member Since: June 28, 2006 Posts: 24 Comments: 8201
Posting from Okinawa Japan and watching Melor. Everyone think this thing is actually going to turn before it hits us here?
Member Since: Posts: Comments:
Quoting Chicklit:
Hopes fade for Indonesian quake victims...
Link
This reminds me an awfully lot of 9-11.
So much sadness in the world and so little we can do.
Member Since: October 9, 2008 Posts: 0 Comments: 8279
616. beell
LOL tf,
not a total ignoration then!
Member Since: September 11, 2007 Posts: 141 Comments: 16265
They just bumped AL90 to 55 kt.

AL 90 2009100500 BEST 0 402N 213W 55 990 EX
Member Since: September 23, 2005 Posts: 14 Comments: 10922
Quoting wunderkidcayman:
so when will we have 91L


not sure, I think the AOI needs to still be better organized for it to be 91L, it might work on becoming organized tonight or in the morning during D-Max.
Member Since: June 28, 2006 Posts: 24 Comments: 8201
Thanks, Skye...no wonder.
I can't see that high.
Member Since: July 11, 2006 Posts: 14 Comments: 11190
Skyepony,

while there was no evidence of a warm-core at the surface I still don't discount the storm had one aloft. It is still possible that some latent heat was release through convection. Thus if the storm is getting part or much of its energy from this process, it cannot be non-tropical and since it it is clearly not tropical, it has to be hybrid - subtropical.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
Hopes fade for Indonesian quake victims...
Link
This reminds me an awfully lot of 9-11.
Member Since: July 11, 2006 Posts: 14 Comments: 11190
so when will we have 91L
Member Since: Posts: Comments:
609. Skyepony (Mod)
Chicklit~ Ex90L is ~40N22W
Member Since: August 10, 2005 Posts: 161 Comments: 37448
Quoting beell:
Check out the MIMIC loop on that Azores Low.
MIMIC_TPW



Nice Beell.
Member Since: Posts: Comments:
607. Skyepony (Mod)
Quoting StormW:


Okay!


StormW~ I don't think I've seen your opinion on ex-90L..
Member Since: August 10, 2005 Posts: 161 Comments: 37448
Quoting Chicklit:

even though oil and vinegar don't really mix, they still go well together!
Yep.
Member Since: October 9, 2008 Posts: 0 Comments: 8279
Quoting Chicklit:

even though oil and vinegar don't really mix, they still go well together!


Problem is here we have more of a gasoline and a match analogy going on...
Member Since: March 10, 2006 Posts: 0 Comments: 10034
Quoting Skyepony:


exactly.. why then didn't the temps rise as it passed.. This was my point from yesterday, watching surface observations with Vince temps rose to 80 & higher as it passed, watching surface obs with ex-90L they don't.. with ex-90L today passing an island we see the pressure drop, the wind shift, while the temps stay steady all day about 70ºF, even drops to 69ºF while the pressure is lowest.. I hope those people had a fall jacket handy..


Ah! I see your point.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
One final mini-burst of activity for the Atlantic for '09? Only time will tell.
Member Since: Posts: Comments:
601. Chicklit
12:54 AM GMT on October 05, 2009
Quoting stormwatcherCI:
Exactly. They just need to learn to take everything with a grain of salt or as they say in Cayman, pick sense from nonsense.

even though oil and vinegar don't really mix, they still go well together!
Member Since: July 11, 2006 Posts: 14 Comments: 11190
600. Skyepony (Mod)
12:53 AM GMT on October 05, 2009
Quoting Weather456:


A warm core is not a warm temperature. A warm core is where the temperature is warmer than the surroundings.



exactly.. why then didn't the temps rise as it passed.. This was my point from yesterday, watching surface observations with Vince temps rose to 80 & higher as it passed, watching surface obs with ex-90L they don't.. with ex-90L today passing an island we see the pressure drop, the wind shift, while the temps stay steady all day about 70ºF, even drops to 69ºF while the pressure is lowest.. I hope those people had a fall jacket handy..
Member Since: August 10, 2005 Posts: 161 Comments: 37448
599. stormwatcherCI
12:50 AM GMT on October 05, 2009
Quoting Chicklit:
no need to turn anything into a personal attack, though, don't you agree? intellectual discussions, on the other hand, are wonderful opportunities to learn something!
Exactly. They just need to learn to take everything with a grain of salt or as they say in Cayman, pick sense from nonsense.
Member Since: October 9, 2008 Posts: 0 Comments: 8279
598. beell
12:50 AM GMT on October 05, 2009
90L is a meso-scale feature

No disagreement there, W456.
Member Since: September 11, 2007 Posts: 141 Comments: 16265
597. GeoffreyWPB
12:50 AM GMT on October 05, 2009
Thanks Drak...A very understandable and reasoned post.
Member Since: September 10, 2007 Posts: 0 Comments: 11011
596. Chicklit
12:49 AM GMT on October 05, 2009
Quoting stormwatcherCI:
Might have to do the same. Many learned people on here and the ones who know next to nothing are always saying the others don't know what they are talking about. I really know nothing but am trying to learn from those who do.
no need to turn anything into a personal attack, though, don't you agree? intellectual discussions, on the other hand, are wonderful opportunities to learn something!
Member Since: July 11, 2006 Posts: 14 Comments: 11190
595. stormwatcherCI
12:49 AM GMT on October 05, 2009
Quoting tornadodude:


well then do us a favor and leave already, go back to your mom's basement where people appreciate you. Dont you have school tomorrow? man I miss 2nd grade
LOL
Member Since: October 9, 2008 Posts: 0 Comments: 8279
594. stormwatcherCI
12:47 AM GMT on October 05, 2009
Quoting Chicklit:
I don't even know where 90L is...
Previously Azores AOI
Member Since: October 9, 2008 Posts: 0 Comments: 8279
593. stormwatcherCI
12:47 AM GMT on October 05, 2009
Quoting Weather456:


first time I ever got an ignore list, I placed him on it. *headaches*
Might have to do the same. Many learned people on here and the ones who know next to nothing are always saying the others don't know what they are talking about. I really know nothing but am trying to learn from those who do.
Member Since: October 9, 2008 Posts: 0 Comments: 8279
592. Chicklit
12:45 AM GMT on October 05, 2009
I don't even know where 90L is...but usually find it very very interesting when people who know what they are talking about disagree.
Member Since: July 11, 2006 Posts: 14 Comments: 11190
591. SouthALWX
12:45 AM GMT on October 05, 2009
2006, from troll to amusing. some of the things are becoming so absurd they're laughable. Honestly? Beyond ban level, it doesn't matter at this point because no one is taking you seriously anymore.
Member Since: August 27, 2008 Posts: 0 Comments: 1497
590. tornadodude
12:45 AM GMT on October 05, 2009
Quoting hurricaneseason2006:


Put me on ignore? I'm not the one sticking around a blog that does not appreciate me - you are the one who suppose to be on ignore.


well then do us a favor and leave already, go back to your mom's basement where people appreciate you. Dont you have school tomorrow? man I miss 2nd grade
Member Since: June 28, 2006 Posts: 24 Comments: 8201
589. Cavin Rawlins
12:43 AM GMT on October 05, 2009
Quoting Skyepony:



It pretty much ran over a weather station in the heat of the day & managed a high of 71F, high wind of 31mph, gust to 44mph, 997mb was the lowest as it past through the S side of the COC. 0.08 in / 0.2 cm. 71F isn't warm core..


A warm core is not a warm temperature. A warm core is where the temperature is warmer than the surroundings. So you are saying the temperature has to be above a certain temperature for it to be warm-core? No. A warm core is when the temperature at the center of a system is warmer than the surrounding temperature.

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

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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.