Hurricane Hunters find 50 - 60 mph winds in disturbance 92L north of Puerto Rico

By: Dr. Jeff Masters , 8:54 PM GMT on August 25, 2009

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The tropical wave (92L) a few hundred miles north of Puerto Rico is generating a large area of surface winds of 50 - 60 mph, according to the latest information from the Hurricane Hunters. Top winds seen so far at their flight level of 1,000 feet were 69 mph, which would make 92L a strong tropical storm if it had a surface circulation.
However, the aircraft has not found a surface circulation, and the satellite appearance shows virtually no change in the amount, intensity, or organization of the storm's thunderstorm activity. Wind shear has dropped to the moderate range, 15 - 20 knots this afternoon, but the upper low 92L is moving underneath is dumping cold, dry air into the region. Dry air continues to get ingested into 92L's thunderstorms, creating strong downdrafts that are robbing 92L of heat and moisture. These downdrafts are creating surface arc clouds that spread out from where the downdraft hits the ocean surface. NHC continues to give 92L a high (greater than 50% chance) of developing into a tropical depression by Thursday afternoon.

The forecast for 92L
As 92L moves underneath the center of the upper low on Wednesday morning, the upper low is expected to weaken, and wind shear is expected to decline to the low range, 5 - 10 knots. However, the upper-level low will continue to dump dry, cold air into 92L through Thursday afternoon, slowing down development. By Thursday night, when 92L should be several hundred miles off the coast of northern Florida, the upper-level low may be weak enough and far enough away that 92L will find itself in a region with light upper level anticyclonic winds, which would favor more rapid development. However, this favorable environment will not last long, since a strong trough of low pressure will be approaching the U.S. East Coast on Friday. This trough will bring high wind shear of 20 - 30 knots by Friday night. This trough should be strong enough to turn 92L to the north. The models disagree substantially on how close 92L will be to the coast at that time. One camp of models, including the NOGAPS, Canadian, UKMET, and ECMWF models, predict 92L will pass very close to the Outer Banks of North Carolina on Friday night or Saturday morning. The GFS, GFDL, and HWRF models keep 92L several hundred miles out to sea. Both sets of models bring 92L north-northeastwards on Saturday, with a track over Massachusetts or Nova Scotia. The intensity forecast for 92L is problematic, since it's eventual strength depends upon how quickly it manages to become a tropical depression. Given that 92L will find itself in a favorable environment for strengthening for about 36 hours this week, and marginal for the remainder of the week, I give the system these odds:

10% chance of never getting a name.
20% chance of becoming a weak tropical storm (40 - 50 mph winds).
40% chance of becoming a strong tropical storm (55 - 70 mph winds).
30% chance of attaining hurricane strength.

Elsewhere in the Atlantic
The ECMWF and UKMET models predict the development of a tropical wave coming off the coast of Africa late this week. The GFS model no longer shows this.

I'll have an update Wednesday morning.

Jeff Masters

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Quoting connie1976:
Do you all think that whatever this storm is that it will stay away from south florida?
>>yup, I'm paranoid<<


It is further to the west of track then they thought.. and to add to the paranoia... it went thru the box. But I have my doubts
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Where is everybody?
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Do you all think that whatever this storm is that it will stay away from south florida?
>>yup, I'm paranoid<<
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Handle: JupiterFL
Status: No-Ads Paid Membership
Expiration: 2010-08-26 20:18:40
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One comment on the $5 membership:
It eliminates the ads and makes everything load on this site much faster. Well worth the money.
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Quoting GeoffreyWPB:
Thanks stormwatcher...I see they just updated.
Looks like it is a little further south than they thought.
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Quoting stormwatcherCI:
25/2345 UTC 22.5N 67.1W T1.5/1.5 92L -- Atlantic
Thanks
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Thanks stormwatcher...I see they just updated.
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Quoting winter123:


can we all trwi ti uez garemammer/speklalling?\?


Not cool
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Quoting GeoffreyWPB:


220. Tazmanian 7:36 PM EDT on August 25, 2009
Quoting GeoffreyWPB:
Almost there..

25/1745 UTC 23.3N 64.8W T1.5/1.5 92L -- Atlantic



thats old

25/2345 UTC 22.5N 67.1W T1.5/1.5 92L -- Atlantic
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278. JLPR
Ukmet develops the wave that is at the coast of Africa

NEW TROPICAL STORM FORECAST TO DEVELOP AFTER 72 HOURS
FORECAST POSITION AT T+ 72 : 11.2N 33.9W

VERIFYING TIME POSITION STRENGTH TENDENCY
-------------- -------- -------- --------
12UTC 28.08.2009 11.2N 33.9W
00UTC 29.08.2009 13.4N 36.0W WEAK INTENSIFYING RAPIDLY
12UTC 29.08.2009 13.0N 38.8W MODERATE INTENSIFYING RAPIDLY
00UTC 30.08.2009 14.0N 41.4W MODERATE INTENSIFYING SLIGHTLY
12UTC 30.08.2009 15.0N 44.3W INTENSE LITTLE CHANGE
00UTC 31.08.2009 15.3N 46.9W INTENSE LITTLE CHANGE
12UTC 31.08.2009 16.5N 48.4W INTENSE LITTLE CHANGE

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Quoting cajunstorm:
Good evening everyone!!!!


good evening!
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Good evening everyone!!!!
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I have pondered not letting the team post on this blog because of some of the anger and jealosy their futuristic forecast stir up.(Wink) But I usually relent in deference to excellence in forecasting. Our prior forecasts are very accurate. That is agreed to by all.
Member Since: August 15, 2007 Posts: 0 Comments: 1304
Quoting Weathermandan:
Most models seem to develop a closed circulation by 6z (2 AM EDT). It appears that the HWRF and GFS lie on the eastern side of the guidance envelope, bringing future "Danny" somewhere near, over, or just east of the 40N/70W benchmark, with the ECMWF, CMC, and UKMET on the west side, near the North Carolina coast and then up into southern New England and Canada (NAM appears in this camp as well, albeit a little stronger) and the GFDL and NOGAPS are more or less up the center of the track guidance. The intensity remains an issue ( = highly uncertain), with the GFDL forecasting a weak tropical storm at its peak over the Gulf Stream, similar to the HWRF, with the SHIPS (and NAM) on the stronger side (a solid CAT 1 hurricane with 85-90+ mph winds) pretty much all the way up the coast as far as I can tell. So my question is, do I have this information correct, and is it even really usable considering this "blob" does not yet have a definitive LLC?

I will say this, future Danny will almost certainly (imo) pass noticably closer to the eastern seaboard than Bill. The 50-60 mph surface winds also concern me. What could be the cause of that, other than downdrafts from thunderstorms. Is it possible the disturbance is acquiring SUBtropical characteristics? Those kind of winds are more indicitive of a gale-type storm rather than something purely tropical.



Not by definition is 92L a subtropical system...these either form under ULL's or along frontal boundaries. 92L has been at the affect of the ULL to its NW but only through divergence (good for convection) and shear (bad for organization).
Member Since: September 4, 2007 Posts: 0 Comments: 491
Quoting KEHCharleston:
From Tropical Positioning Page

25/1745 UTC 23.3N 64.8W T1.5/1.5 92L -- Atlantic


220. Tazmanian 7:36 PM EDT on August 25, 2009
Quoting GeoffreyWPB:
Almost there..

25/1745 UTC 23.3N 64.8W T1.5/1.5 92L -- Atlantic



thats old

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Looks like 92 will be a tropical depresssion or a tropical storm very soon. 93L will likely track across mexico and develop into a tropical storm or hurricane.
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besides that its 8 pm time for most to do there homework then get ready for bed school tomorrow

lol
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Your Membership:
Handle: tornadodude
Status: Free Membership
Expiration:
Signed Up: 2006-06-28 14:24:08
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Quoting JLPR:
the blog is kinda dead again today =\
2 updates today JLPR thats why it seems like a slow low number day
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From Tropical Positioning Page

25/1745 UTC 23.3N 64.8W T1.5/1.5 92L -- Atlantic
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Quoting KEEPEROFTHEGATE:
always been keeperofthegate started in mid aug of 05 picked my screen picture on aug 29 05 became a paid member in july of 06 never used another handle always been the one i have

You have posted 143 entries in your own blog.

You have posted 20996 comments in all blogs.

View Your WunderBlog!

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2744 comments and 52 entries posted by all members in the last 24 hours.


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Handle: KEEPEROFTHEGATE
Status: No-Ads Paid Membership
Expiration: 2010-08-20 03:03:45
Signed Up: 2006-07-15 14:37:36


anything else


A whopper meal please hold the mayo.
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Quoting tropicfreak:


Just out of curiosity, but are you the old STORMTOP?
always been keeperofthegate started in mid aug of 05 picked my screen picture on aug 29 05 became a paid member in july of 06 never used another handle always been the one i have

You have posted 143 entries in your own blog.

You have posted 20996 comments in all blogs.

View Your WunderBlog!

Blog Statistics:
2744 comments and 52 entries posted by all members in the last 24 hours.


Search The Blogs:


Handle: KEEPEROFTHEGATE
Status: No-Ads Paid Membership
Expiration: 2010-08-20 03:03:45
Signed Up: 2006-07-15 14:37:36


anything else
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264. JLPR
the blog is kinda dead again today =\
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Quoting Hhunter:
for real?
Sounds real ?.?
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Quoting juniormeteorologist:


I was watching it on some channel, but I don't know what channel it was, I know it wuz a station in Horry, but as far as the Call Signs, I have no clue, but my kids are in school, so hopefully if this thing come it will be late Friday night into that Saturday morning so that they won't have to miss a day the first week back.

Ahh... Yea, y'all in Horry County stick out a bit farther into the Atlantic than we do in Charleston and points south.
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Quoting bwat:
Just read the entry for KerryinNOLA and had this thought.Link


lol, thanks, some people just "get it"!
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Tropicfreak, The reason i asked is because the convection on the sat looks like its moving NW.
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Quoting tropicfreak:


Just out of curiosity, but are you the old STORMTOP?



no he is not stormtop i have new keeper from the time i have started posted on WU
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258. bwat
Just read the entry for KerryinNOLA and had this thought.Link
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257. JRRP
Link
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Quoting KEEPEROFTHEGATE:
your detailed flush model anal of information has out perform you


Just out of curiosity, but are you the old STORMTOP?
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254. VARob
Quoting tropicfreak:


I am already prepared, even though I live more inland from VA Beach in Richmond however, one cannot let their guard down.


Neighbor..almost. I'm in White Stone on the bay.
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Quoting stormsurge39:
Is there anything to the reminants of 93l left over in the SW Carribean?


No. 93L is crossing into the eastern pacific and will likely become a TD.
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Quoting KEEPEROFTHEGATE:
your detailed flush model anal of information has out perform you


Honestly I dont know why he bothers posting on this blog. Once I saw KERRYINNOLA I automatically skip his posts lol. Does he have a reputation? I have never heard of this in-significant person before.
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looks like the E PAC will be join by 94E and 95E soon
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Quoting juniormeteorologist:


I was watching it on some channel, but I don't know what channel it was, I know it wuz a station in Horry, but as far as the Call Signs, I have no clue, but my kids are in school, so hopefully if this thing come it will be late Friday night into that Saturday morning so that they won't have to miss a day the first week back.


I'm sure they would love to miss some school.
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Is there anything to the reminants of 93l left over in the SW Carribean?
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Quoting KEHCharleston:


Hi juniormeterologist,
Charleston, here.

Which mets?

NWS for Charleston:
.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
12Z GUIDANCE AGREES THAT A TROPICAL LOW WILL TURN TOWARD THE N/NE
AND WILL PASS EAST OF THE REGION
LATE THIS WEEK/EARLY THIS WEEKEND.
HOWEVER...THE STRENGTH OF THE SYSTEM AND THE LONGITUDE OF THE N/NE
TURN REMAIN HIGHLY UNCERTAIN. AS OF TUESDAY AFTERNOON...THE MOST
LIKELY IMPACTS...IF ANY...WOULD INCLUDE SOME DEGREE OF ENHANCED
WINDS/BUILDING SEAS OVER COASTAL WATERS.


I was watching it on some channel, but I don't know what channel it was, I know it wuz a station in Horry, but as far as the Call Signs, I have no clue, but my kids are in school, so hopefully if this thing come it will be late Friday night into that Saturday morning so that they won't have to miss a day the first week back.
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NWS info for anyone in North Carolina.

Short term /Wednesday night through Friday night/...
a cold front will settle just north of the County Warning Area on Thursday...while
a weak upper level disturbance will drift from the southeastern
states into the Carolinas later Friday. Model soundings do show a
decent cap on Thursday...and with dewpoints near or in the lower
60s...and little if any forcing...shws/stms may just be confined to
the higher elevations of northwest NC/SW Virginia/southeast WV. Also...a developing
downsloping wind is drying out the midlevels substantially. As a
trough digs through the upper Midwest...surface high pressure
darting across New England should allow southeast to east upslope flow to
strengthen on Friday. Good surface convergence combined with the
upper level disturbance moving closer...should allow shws and storms
to develop and spread from SW to NE during the day. Considering the
above...did lower maximum temperatures this day. At this time...a lot of
uncertainty exists regarding a potential tropical system off the southeast
coast...with the European model (ecmwf) closest to our region later Friday and Friday
night. However...even if the system stays farther away per the
GFS...the upslope component will be strengthened per the pressure
gradient...making rain more probable anyways.



Long term /Saturday through Tuesday/...
this weekend's forecast will largely depend upon the development
of a tropical wave NE of Puerto Rico...and how it may affect the
southeast coast. At the same time...a formidable cold front will
cross late in the weekend. Tried to follow HPC probability of precipitation on
Saturday...as there is a split in the long range suite regarding
any potential track of the potential system....with the European model (ecmwf) the
farthest west. The 12z GFS does have the system closer to the
coast than its previous run. Long range model's fast bias in
regards to the speed of cold fronts/troughs lends credence towards
a more westward track.
Behind the cold front...a much cooler
airmass will arrive with even the typically warm European model (ecmwf) down to +8c
at 850 mb. Through early next week...some minimum temperatures could
hit the 40s in extreme SW Virginia and southeast West Virginia.

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246. JLPR
Quoting Tazmanian:
a dustcaster is when some one says there a lot of dust but there not


lol Taz there is dust but its still on shore
there is definitely very little on the sea
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Quoting bingcrosby:
Who started the africa wave train? lol


Bob Hope We're off on the road through the tropics.
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Most models seem to develop a closed circulation by 6z (2 AM EDT). It appears that the HWRF and GFS lie on the eastern side of the guidance envelope, bringing future "Danny" somewhere near, over, or just east of the 40N/70W benchmark, with the ECMWF, CMC, and UKMET on the west side, near the North Carolina coast and then up into southern New England and Canada (NAM appears in this camp as well, albeit a little stronger) and the GFDL and NOGAPS are more or less up the center of the track guidance. The intensity remains an issue ( = highly uncertain), with the GFDL forecasting a weak tropical storm at its peak over the Gulf Stream, similar to the HWRF, with the SHIPS (and NAM) on the stronger side (a solid CAT 1 hurricane with 85-90+ mph winds) pretty much all the way up the coast as far as I can tell. So my question is, do I have this information correct, and is it even really usable considering this "blob" does not yet have a definitive LLC?

I will say this, future Danny will almost certainly (imo) pass noticably closer to the eastern seaboard than Bill. The 50-60 mph surface winds also concern me. What could be the cause of that, other than downdrafts from thunderstorms. Is it possible the disturbance is acquiring SUBtropical characteristics? Those kind of winds are more indicitive of a gale-type storm rather than something purely tropical.
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000
ABPZ20 KNHC 252331
TWOEP
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
500 PM PDT TUE AUG 25 2009

FOR THE EASTERN NORTH PACIFIC...EAST OF 140 DEGREES WEST LONGITUDE..

THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON TROPICAL
STORM IGNACIO...LOCATED ABOUT 710 MILES WEST-SOUTHWEST OF THE
SOUTHERN TIP OF BAJA CALIFORNIA.

AN AREA OF DISTURBED WEATHER HAS DEVELOPED SEVERAL HUNDRED MILES
SOUTH-SOUTHWEST OF THE SOUTHWESTERN COAST OF MEXICO. ENVIRONMENTAL
CONDITIONS APPEAR CONDUCIVE FOR SOME SLOW DEVELOPMENT OF THIS
SYSTEM AS IT MOVES WEST TO WEST-NORTHWESTWARD NEAR 10 MPH OVER THE
NEXT COUPLE OF DAYS. THERE IS A LOW CHANCE...LESS THAN 30
PERCENT...OF THIS SYSTEM BECOMING A TROPICAL CYCLONE DURING THE
NEXT 48 HOURS.

A BROAD AREA OF LOW PRESSURE LOCATED OVER CENTRAL AMERICA IS MOVING
WESTWARD AT 10 TO 15 MPH AND WILL BE MOVING INTO THE EASTERN NORTH
PACIFIC OCEAN TONIGHT. DEVELOPMENT OF THIS SYSTEM...IF ANY...
SHOULD BE SLOW TO OCCUR TO DUE ITS PROXIMITY TO LAND. THERE IS A
LOW CHANCE...LESS THAN 30 PERCENT...OF THIS SYSTEM BECOMING A
TROPICAL CYCLONE DURING THE NEXT 48 HOURS. REGARDLESS OF
DEVELOPMENT...LOCALLY HEAVY RAIN IS EXPECTED OVER PORTIONS OF
CENTRAL AMERICA AND EXTREME SOUTHEASTERN MEXICO OVER THE NEXT DAY
OR TWO.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.
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Quoting tropicfreak:


go shout in the chat room

Funny that almost all of the posts about actually going in there have been in all caps. Probably loud in there.
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bastardi does tends to oversell things sometimes..but i think this system 92L he may actually be on to something with this being a strong east coast storm....you heard it hear first...stay on your toes midatlantic north...
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Who started the africa wave train? lol
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Quoting jipmg:


Maybe a strong Sub tropical storm, Water temperatures arent the only factors in storm development

Yeah, I don't know how to tell what GFS is figuring on. Omega?
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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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