High wind shear ripping into 97L

By: Dr. Jeff Masters , 1:49 PM GMT on July 20, 2009

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A strong tropical wave (97L) a few hundred miles east of Barbados in the Lesser Antilles Islands has grown less organized today as it tracks west at 15 - 20 mph. The wave is moving underneath an upper-level trough of low pressure, which is bringing 30 knots of wind shear to 97L. While there is a respectable amount of heavy thunderstorm activity associated with 97L, there is no longer any low-level spiral banding or rotation of the cloud pattern. This morning's QuikSCAT pass at 5:35 am EDT showed sustained winds of 35 mph a few hundred miles east of Barbados, but there was no surface circulation evident. The islands of Barbados, St. Vincent and the Grenadines, St. Lucia, and Martinique can expect heavy rain and wind gusts to 50 mph as 97L moves through the Lesser Antilles Islands this afternoon and tonight, but 97L will not become a tropical depression.

Wind shear along the path of 97L is forecast to remain in the high 25 - 35 knot range for at least the next three days. This should prevent further development of 97L, and I expect the disturbance will be gradually torn apart during the next few days. The National Hurricane Center gives 97L a low (less than 30% chance) of developing into a tropical depression in the next 48 hours. None of the computer models are forecasting any tropical storm development over the next seven days.


Figure 1. Current satellite image of African wave 97L.

I'll have an update Tuesday morning. As 97L moves through the islands, you may want to follow local observations there using our wundermap for the region.

Jeff Masters

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Quoting Drakoen:
King Shear still has it's grip on 97L according to 21z.


actually I see the shear decreasing now, but still too hostile at this time for development
Quoting TheWeatherMan504:


I have been tracking Hurricanes since 1992, I was in High School. After that night of Andrew in SE LA I was hooked to the weather in general. Then in 1998 me and my buddies went chasing for Georges in Mississippi and we managed to get in the eye. Put it this way, being in the eye of a Hurricane is very eerie.


I was in the eye of Tropical Storm Fay.. but that's a completely different story lol
Member Since: July 1, 2008 Posts: 13 Comments: 7340
update is out at cimss
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1459. 7544

Wave near 40W has got plenty of arguments written all over it.....


that should bring in 1000 xtra post lol
Member Since: May 6, 2007 Posts: 0 Comments: 6694
1457. Drakoen
King Shear still has it's grip on 97L according to 21z.
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1456. K8eCane
Quoting Acemmett90:

its alive and ticking 23 no need to deacvtivate it



23 doesnt have the power to deactivate it
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Quoting reedzone:


Everyone is capable of analyzing the weather. I have been tracking storms since 1999, when I was in the 6th grade. Conditions are not favorable for a TD, I know this. I am NOT a wishcaster, I back up my stuff with details from the pattern and sometimes models, not all the time. I still hold on to my guns that 97L eventually this week will form into a TD at best. It's doing ok in high wind shear, still blowing convection near the LLC, though it's getting sheared to the east.. but still, no reason to de-activate it, absolutely no reason, especially when it FINALLY has model support. :)


I have been tracking Hurricanes since 1992, I was in High School. After that night of Andrew in SE LA I was hooked to the weather in general. Then in 1998 me and my buddies went chasing for Georges in Mississippi and we managed to get in the eye. Put it this way, being in the eye of a Hurricane is very eerie.
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Geeeesh, folks, I'll be back later when recess is over.
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Quoting KEEPEROFTHEGATE:


new convective refire detected nw of previous
area as of 626 pm edt


I see Keeper, thanks for all those updates :)
As I said earlier, 97L is a fighter.
Member Since: July 1, 2008 Posts: 13 Comments: 7340
Quoting Drakoen:
Adrian is constantly burned down for his conservative opinions. It is natural for him to respond in such a manner. You don't have to like it. I doubt Adrian cares about personality judgments.


Hey its no problem ive not once ever direspected anyone on this blog and ive been here since 04.Posting the TWO 50 times,is it coming to miami,the NHC questioning its all just annoying and honestly pretty ridiculous.
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Quoting KEEPEROFTHEGATE:


new convective refire detected nw of previous
area as of 626 pm edt

Keep, is there an animation with that link, please? Thanks.
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Quoting IKE:
Wave near 40W has got plenty of arguments written all over it.....



wave looks decent, very far south in the ITCZ, shear is around 20 knots in that area
1447. Drakoen
Quoting IKE:
Wave near 40W has got plenty of arguments written all over it.....




lol
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Quoting KEEPEROFTHEGATE:


new convective refire detected nw of previous
area as of 626 pm edt


lol you are making me laugh with the reports, like you are on radar detail or a robot

not being sarcastic, I think the posts are awesome lol
Geeesh, yeah, it's a mess alight. I'm getting cross-eyed looking at that radar - it looks as if there's a coc over St. Vincent, then another west of St. Lucia...and both are void of convection over the tops.
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1443. IKE
Wave near 40W has got plenty of arguments written all over it.....

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1442. 7544
lloks like 97l is getting dressed again looks like it put on a new outfit much better then the last ones
Member Since: May 6, 2007 Posts: 0 Comments: 6694
Quoting hurricane23:
Ahhhhhhh! Yea the spin in the bahamas will spin up later this evening and have a pressure drop of 90mb in 2hrs. 97 will also develope a surface circulation in the next 20 minutes in the face of very hostile upper conditions with digging trof in the gulf which only futher increase the south westerly shear down there.


Your just being ridiculous now.. I dunno why so many experts have attitudes! I'm not predicting a hurricane for gosh sake. We can agree to dissagree. I don't care if you dissagree, we are ALL subject to our opinions. But PLEASE respect me and what I do and I'll respect you in what you do! I'm a Christian, I don't fight like most do on here.
Member Since: July 1, 2008 Posts: 13 Comments: 7340
1440. KEEPEROFTHEGATE (Mod)


new convective refire detected nw of previous
area as of 626 pm edt
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1439. K8eCane
23
your posts are like everyone elses on here
just posts
i for one take em with a grain of salt
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Quoting Drakoen:
Adrian is constantly burned down for his conservative opinions. It is natural for him to respond in such a manner. You don't have to like it. I doubt Adrian cares about personality judgments.


I second that.
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Quoting Drakoen:
Adrian is constantly burned down for his conservative opinions. It is natural for him to respond in such a manner. You don't have to like it. I doubt Adrian cares about personality judgments.


maybe if he didnt come in and act like he is better than everyone, people wouldnt react that way to him
Quoting futuremet:


He is actually making a good point for once


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Earlier today Trinidad had some thunder showers but for now there is no kind of cloud cover to talk about. Thanks for the update :)
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1434. aquak9
Nothing like a dose of downright stiff sarcasm to get the respect of fellow bloggers there, 23.
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Quoting reedzone:


Everyone is capable of analyzing the weather. I have been tracking storms since 1999, when I was in the 6th grade. Conditions are not favorable for a TD, I know this. I am NOT a wishcaster, I back up my stuff with details from the pattern and sometimes models, not all the time. I still hold on to my guns that 97L eventually this week will form into a TD at best. It's doing ok in high wind shear, still blowing convection near the LLC, though it's getting sheared to the east.. but still, no reason to de-activate it, absolutely no reason, especially when it FINALLY has model support. :)


Its doing ok? I cant even make out the mid level circulation it once had.
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1431. 7544
keeping one eye on the bahammas wave and invest 97l looks like so fla will get alot of wet pockets from these two and possibly the one behind 97l stay tuned
Member Since: May 6, 2007 Posts: 0 Comments: 6694
1430. Drakoen
Adrian is constantly burned down for his conservative opinions. It is natural for him to respond in such a manner. You don't have to like it. I doubt Adrian cares about personality judgments.
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1429. viman
Quoting BurnedAfterPosting:


and 456 has a much better attitude and treats people a lot better


I agree
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1428. Drakoen
Quoting SLU:


The center is west of St. Lucia. I witnessed 1st hand what happened as the center passed by.
The winds veered from NE to South @ 15mph and the rotation in the clouds also changed as the center passed. Even the radar shows the rotation just SW of Martinique and west of St. Lucia. No way it could still be to east.

Link


If the center is west of there then 97L just committed suicide. Also it's very easy for those winds to just be locally influenced since it's an island.
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Quoting hurricane23:
Ahhhhhhh! Yea the spin in the bahamas will spin up later this evening and have a pressure drop of 90mb in 2hrs. 97 will also develope a surface circulation in the next 20 minutes in the face of very hostile upper conditions with digging trof in the gulf which only futher increase the south westerly shear down there.


Its these kinds of posts that make people not respect your opinion regardless of your credentials
1426. KEEPEROFTHEGATE (Mod)


INV/97L/XX
MARK
13.6N/60.6W
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1424. K8eCane
Quoting BurnedAfterPosting:


and 456 has a much better attitude and treats people a lot better


exactly
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Quoting hurricane23:


Dr masters approval your kidding right? Your point is? Iam about to finish my bachelor's degree from florida state university and i think iam pretty capable of analyzing whats out there.Everyone is entitled to there on perspective on things i'll give you that.The tropics basin wide are hostile and i continue to hold on development in august.


Everyone is capable of analyzing the weather. I have been tracking storms since 1999, when I was in the 6th grade. Conditions are not favorable for a TD, I know this. I am NOT a wishcaster, I back up my stuff with details from the pattern and sometimes models, not all the time. I still hold on to my guns that 97L eventually this week will form into a TD at best. It's doing ok in high wind shear, still blowing convection near the LLC, though it's getting sheared to the east.. but still, no reason to de-activate it, absolutely no reason, especially when it FINALLY has model support. :)
Member Since: July 1, 2008 Posts: 13 Comments: 7340
1422. SLU
Quoting Drakoen:
There is no way it is west of St. Lucia. That would mean it traveled almost 140 miles since it's 18z fix. I have the center at 13.4N 60.4W.


The center is west of St. Lucia. I witnessed 1st hand what happened as the center passed by.
The winds veered from NE to South @ 15mph and the rotation in the clouds also changed as the center passed. Even the radar shows the rotation just SW of Martinique and west of St. Lucia. No way it could still be to east.

Link
Member Since: July 13, 2006 Posts: 12 Comments: 4905
All four stations on St. Lucia that are on WU are showing S so SE winds, which would support that circ on radar.
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Quoting K8eCane:



I on the other hand would not. I find Weather456s forecasts to be extremely informative and accurate


and 456 has a much better attitude and treats people a lot better
1419. eddye
97L
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1418. aquak9
Docmasters did give 456 props a while back, said to follow his blog while he was away, something like that.

Not to take ANY credit away from a BS degree.

But some of the older folks here do have a helluva lotta life experience to support their opinions.
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Quoting eddye:
everyone look behind 9 l that one has a better chance of developing


He is actually making a good point for once
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Adrian - Just was wondering if you could explain why you have stated that "there's nothing down there" with Invest 97L when surface observations throughout the day both in Barbados and St. Lucia indicate that there's a surface circulation.

Believe me, I have great respect for you and your knowledge, but given the decent low-level vorticity and surface observations, I would have to respectfully disagree with your conclusion.
Member Since: April 14, 2007 Posts: 8 Comments: 5163
1415. K8eCane
Quoting Drakoen:


I'd take the Bachelors Degree lol



I on the other hand would not. I find Weather456s forecasts to be extremely informative and accurate
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1414. 7544
july 20 watching 3 waves . now
Member Since: May 6, 2007 Posts: 0 Comments: 6694
1413. eddye
everyone look behind 9 l that one has a better chance of developing
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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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