WunderBlog Archive » Category 6™

Category 6 has moved! See the latest from Dr. Jeff Masters and Bob Henson here.

97L Dumping Heavy Rains on Puerto Rico, Virgin Islands

By: Dr. Jeff Masters, 3:31 PM GMT on September 04, 2013

A tropical wave over the Northeast Caribbean (Invest 97L) is slowly growing more organized as it moves west-northwest at 10 mph towards Puerto Rico and the Dominican Republic. Winds gusts of 36 mph have been recorded this morning at buoy 41052 south of St. John in the Virgin Islands, and heavy thunderstorms from 97L have dumped over an inch of rain in many locations in the Virgin Islands and Northern Puerto Rico as of 11 am AST Wednesday. Puerto Rico doesn't need the rain, as they have had one of their wettest years on record; San Juan is nearly two feet (23.49") above average in rainfall for the year. Satellite loops show that 97L has a moderate amount of spin and heavy thunderstorms, with a respectable upper-level outflow channel to the north. There is no sign of a well-organized surface circulation. Long-range radar out of San Juan, Puerto Rico shows some modest spin to 97L's echoes, but no well-organized low-level spiral bands. Upper level winds are favorable for development, with wind shear a low 5 - 10 knots. There is some dry air from the Saharan Air Layer (SAL) that is interfering with development, but this is becoming less of an issue as heavy thunderstorms from 97L continue to moisten the storm's environment.


Figure 1. True-color MODIS satellite image of 97L taken at 1:30 pm EDT on September 4, 2013. Image credit: NASA.

Forecast for 97L
Wind shear is expected to be low through Friday night, and ocean temperatures will be warm, 29°C. One wild card is how 97L will interact with a strong tropical wave about 500 miles to its east, just east of the Lesser Antilles Islands. This new tropical wave may compete for moisture, slowing development of 97L, and could also modify the track of 97L. The models take 97L to the west-northwest, bringing the center over the eastern tip of the Dominican Republic on Thursday morning. This track will allow the high mountains of Puerto Rico and Hispaniola to disrupt the circulation of 97L, forcing the storm to regroup on Friday over the Southeast Bahamas and Turks and Caicos Islands. The best chance for development of 97L would appear to be on Saturday, after the storm has had time to recover from its encounter with Hispaniola. The UKMET model predicts that 97L will become a tropical depression just north of the Southeast Bahamas and Turks and Caicos Islands on Saturday, but the GFS and European models show little development over the next three days. There will be a strong trough of low pressure off the U.S. East Coast this weekend, and the models predict that this trough will be strong enough to turn 97L to the north and northeast by Sunday, keeping 97L well offshore from the U.S. East Coast, but with a possible threat to Bermuda next week. In their 8 am EDT Wednesday Tropical Weather Outlook, NHC boosted the 5-day odds of formation of 97L to 60%, and 2-day odds to 40%. The Hurricane Hunters are on call to investigate 97L Wednesday afternoon. The Hurricane and Severe Storm Sentinel Mission, a 5-year field project utilizing two remotely crewed Global Hawk aircraft to overfly tropical storms and hurricanes, will have one of their aircraft investigate 97L today. You can follow the progress of the aircraft using NASA's live-plane tracker map (Global Hawk AV6 is tail number NASA872, and Global Hawk AV1 is tail number NASA871.)

Regardless of whether or not 97L becomes a tropical depression today, the major danger from this slow-moving storm will be heavy rains. Three to six inches of rain are predicted to fall over Puerto Rico and the Virgin Islands by Thursday morning, with 3-day rainfall totals of 5 - 10 inches expected along the south and southeast shores of Puerto Rico. These rains are capable of causing dangerous flash flooding and mudslides, and a Flash Flood Watch has been posted. Similar rainfall amounts will fall in the eastern Dominican Republic, and heavy rains of 3 - 6 " are also likely to affect the Southeast Bahamas and Turks and Caicos Islands later in the week. Since 97L is relatively small, Haiti may see lower rainfall amounts of 2 - 4 inches.

Elsewhere in the Atlantic
A tropical wave over Mexico's Yucatan Peninsula and adjacent waters of the Gulf of Mexico is causing scattered disorganized heavy thunderstorms. This activity will move over the extreme Southern Gulf of Mexico's Bay of Campeche on Wednesday and Thursday, then moving ashore on the Mexican coast between Veracruz and Tampico on Friday. In their 8 am EDT Wednesday Tropical Weather Outlook, NHC put the 5-day and 2-day odds of development at 20%.

A strong tropical wave is predicted to emerge from the coast of Africa on Saturday, and the GFS model develops this wave into a tropical depression near the Cape Verdes Islands by Monday. The storm is expected to track to the northwest into a region of ocean where very few tropical cyclones ever make the long crossing of the Atlantic Ocean to threaten North America.

Jeff Masters

Hurricane

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

Quoting 1478. BahaHurican:
I'm starting to wonder if some kind of Fujiwara - type interaction between TD 7 and the wave behind it may contribute to that more northward track in the next 48 hrs... and for CI... I am more curious as to whether the models took that westward drifting weakness into consideration.

This is what I have been looking at too.. people are seeing the upper level cloud tops join and say 7 is feeding off the wave but storms feed from the bottom..
1502. Patrap
TD 7 knows what day it iz.



1503. ncstorm
Looks familiar? was supposed to turn NE

I'm no expert but it looks to me like the second disturbance is being influenced by the ULL dropping SW from the western Atllantic I.e. the ne- sw orientation of the HL moisture.
Quoting 1498. BahaHurican:

It helps to actually look at the NHC graphics. Remember the meaning of the cone.

so CI, you may be right, but it seems the track forecast does somewhat take your thinking into account.
I will watch it until it is gone because it wouldn't be the first time a TS or hurricane has not done what the NHC or other experts said they would. Sometimes I think they don't get the memo.
Quoting 1471. Grothar:
I was just called to answer a few questions, so here goes

ncstorm - yes, but it could change
taco - Did you ever consider the alternative?
opal - Yes, but what about 1995
Bluestorm - I already learned that in 1954
TropicalAnalyst- Possible, but what about the other one?

wunderkidcayman - It's not going west
PATRAP - Why don't you post the image of TD7 every 3 frames in case we forget what it looks like.
GeoffWPB - yes, you're still a twit!
KEPPER - I've heard that one before.

See you all later. Play nicey nice.


P.S. HurricaneJoe, no still no hug.
Now that's what I call power blogging... lol

...TROPICAL DEPRESSION DRIFTING NORTH-NORTHWESTWARD...
...EXPECTED TO BECOME A TROPICAL STORM TONIGHT OR TOMORROW...
Continues to maintain a great structure. The difference between today and virtually every other disturbance to date is that 07L has had a sufficiently well-defined circulation providing for continuous convergence at the surface to allow thunderstorm activity to persistently flourish even during the most atmospherically stable hours of the day.

Nice banding features beginning to develop along the eastern flank.

I'd say we have an intensifying tropical cyclone.



Quoting 1502. Patrap:
TD 7 knows what day it iz.

All right!
Stop whatcha doin'
'cause I'm about to ruin
the image and the style that ya used to.
I look funny




That's about the only rap song I ever liked. The lyrics are funny as all get out.
The Humpty Hump.
good evening folks. I been at school all day just got home....I see we now have TD 7 and look at the Ensemble models....these models are hinting at another Sandy track ?



Link
...so much for the western movement LOL.


Llc of td will be exposed in within the next few hours The llc is moving west while the mid level vorticity is moving nw.... another one bites the dust poof!!
Thought this would be up by now

000
WTNT32 KNHC 042337
TCPAT2

BULLETIN
TROPICAL DEPRESSION SEVEN INTERMEDIATE ADVISORY NUMBER 1A
NWS NATIONAL HURRICANE CENTER MIAMI FL AL072013
800 PM AST WED SEP 04 2013

...TROPICAL DEPRESSION DRIFTING NORTH-NORTHWESTWARD...
...EXPECTED TO BECOME A TROPICAL STORM TONIGHT OR TOMORROW...


SUMMARY OF 800 PM AST...0000 UTC...INFORMATION
----------------------------------------------
LOCATION...16.7N 66.2W
ABOUT 120 MI...190 KM S OF SAN JUAN PUERTO RICO
ABOUT 195 MI...315 KM SE OF PUNTA CANA DOMINICAN REPUBLIC
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...NNW OR 330 DEGREES AT 2 MPH...4 KM/H
MINIMUM CENTRAL PRESSURE...1008 MB...29.77 INCHES
1514. JLPR2
10% circle for the TW to the NE of TD 7



A LARGE AREA OF DISORGANIZED SHOWERS AND THUNDERSTORMS LOCATED TO
THE NORTHEAST OF THE LEEWARD ISLANDS IS ASSOCIATED WITH A SURFACE
TROUGH. ANY DEVELOPMENT OF THIS SYSTEM IS EXPECTED TO BE LIMITED
DUE TO ITS PROXIMITY TO TROPICAL DEPRESSION SEVEN. THIS SYSTEM HAS
A LOW CHANCE...10 PERCENT...OF BECOMING A TROPICAL CYCLONE DURING
THE NEXT 48 HOURS AS IT MOVES NORTHWESTWARD AT 10 TO 15 MPH.
DEVELOPMENT IS NOT EXPECTED AFTER 48 HOURS...AND THIS SYSTEM HAS A
LOW CHANCE...10 PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE
NEXT 5 DAYS.
Quoting 1495. sailingallover:

It would form a separate storm back around 60W
I did go back and look at what u r talking about, which is why I started thinking about the Fujiwara thing again. If u r right about a separate storm, would that just follow Gabrielle, or move off to the west?

This looks to be an interesting day or two.
Quoting MiamiHurricanes09:
Continues to maintain a great structure. The difference between today and virtually every other disturbance to date is that 07L has had a sufficiently well-defined circulation providing for continuous convergence at the surface to allow thunderstorm activity to persistently flourish even during the most atmospherically stable hours of the day.

Nice banding features beginning to develop along the eastern flank.

I'd say we have an intensifying tropical cyclone.



Yes and approaching puerto Rico from the South, i think is moving NNW,, straight toward us....
1517. JRRP
Quoting 1511. MiamiHurricanes09:
...so much for the western movement LOL.

It jogged N now it moving W so there is your NNW drift it just started its W movement just wait and see if that W movement continues the it can properly be called a W movement if it starts going N then it will remain NW-NNW movement
Quoting 1511. MiamiHurricanes09:
...so much for the western movement LOL.
Isn't this an intermediate advisory which would just continue with the info from the last advisory ?
GFDL says NHC you made it a cyclone, forget about that Cat 3 stuff


HOUR: 0.0 LONG: -65.84 LAT: 16.10 MIN PRESS (hPa): 1008.72 MAX SURF WIND (KNOTS): 27.06
HOUR: 6.0 LONG: -66.85 LAT: 16.19 MIN PRESS (hPa): 1008.26 MAX SURF WIND (KNOTS): 25.82
HOUR: 12.0 LONG: -67.75 LAT: 16.66 MIN PRESS (hPa): 1007.86 MAX SURF WIND (KNOTS): 22.65
HOUR: 18.0 LONG: -68.95 LAT: 17.14 MIN PRESS (hPa): 1008.90 MAX SURF WIND (KNOTS): 26.12
HOUR: 24.0 LONG: -69.56 LAT: 17.46 MIN PRESS (hPa): 1008.51 MAX SURF WIND (KNOTS): 26.38
HOUR: 30.0 LONG: -69.98 LAT: 17.41 MIN PRESS (hPa): 1009.44 MAX SURF WIND (KNOTS): 26.59
HOUR: 36.0 LONG: -70.63 LAT: 17.65 MIN PRESS (hPa): 1008.55 MAX SURF WIND (KNOTS): 28.58
HOUR: 42.0 LONG: -72.75 LAT: 17.21 MIN PRESS (hPa): 1008.88 MAX SURF WIND (KNOTS): 15.46
HOUR: 48.0 LONG: -73.60 LAT: 17.28 MIN PRESS (hPa): 1008.16 MAX SURF WIND (KNOTS): 12.50
-99.9 -99.90 -99.90
1521. GatorWX
Quoting 1420. HurricaneHunterJoe:


Chhh Chhh Chillin on Boca Grande Island?


Di di di dats right, when I'm fishing/working/playing. It's Gasparilla Island actually. I live/blog off island. Boca is no place for blogging. Good times, that island, good times!!
1522. Grothar
Quoting 1496. redwagon:


I guess I'll just.... continue being....chopped liver. :(



I'm sorry, I didn't mean to leave anyone out. So here you go:

redwagon - You're completely wrong. :)

I really do have to go now.

And Joe, it was Perry Mason.
How are all my Puerto rican friends weather fairing?.Give us updates!.


Latest radar loops suggest an almost due west movement,BTW , yes I'm a westcaster and proud of it :)),also I tell it like I see it!
Quoting 1503. ncstorm:
Looks familiar? was supposed to turn NE

Much better example is Ike.
Quoting 1502. Patrap:
TD 7 knows what day it iz.





So does a drunk camel.
1527. GatorWX
Quoting 1514. JLPR2:
10% circle for the TW to the NE of TD 7



A LARGE AREA OF DISORGANIZED SHOWERS AND THUNDERSTORMS LOCATED TO
THE NORTHEAST OF THE LEEWARD ISLANDS IS ASSOCIATED WITH A SURFACE
TROUGH. ANY DEVELOPMENT OF THIS SYSTEM IS EXPECTED TO BE LIMITED
DUE TO ITS PROXIMITY TO TROPICAL DEPRESSION SEVEN. THIS SYSTEM HAS
A LOW CHANCE...10 PERCENT...OF BECOMING A TROPICAL CYCLONE DURING
THE NEXT 48 HOURS AS IT MOVES NORTHWESTWARD AT 10 TO 15 MPH.
DEVELOPMENT IS NOT EXPECTED AFTER 48 HOURS...AND THIS SYSTEM HAS A
LOW CHANCE...10 PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE
NEXT 5 DAYS.


Well that was unexpected.
1528. GatorWX
Evening Groth!
07L sure isn't a very large tropical cyclone, especially when one looks at radar.
1531. JLPR2
Quoting 1523. washingtonian115:
How are all my Puerto rican friends weather fairing?.Give us updates!.


Not much to report at the moment, light showers and a great sunset.
XD
Quoting 1519. stormwatcherCI:
Isn't this an intermediate advisory which would just continue with the info from the last advisory ?
They use a 6 hour mean. The previous advisory had a 305˚ heading, whereas the intermediate had a 330˚ heading.
1533. Patrap
My memory is muddy, what's this river that I'm in?
New Orleans is sinking, man, and I don't want to swim



Quoting 606. JeffMasters:
Looks like 97L is now pulling in the tropical wave to its NE over the Northern Lesser Antilles. This will make the storm much larger, but may slow down intensification. Hurricane Katrina jumped markedly in size over the Gulf of Mexico when it did something similar--ingest a separate tropical disturbance and steal its spin and moisture.

Dr. M.
Quoting 1505. stormwatcherCI:
I will watch it until it is gone because it wouldn't be the first time a TS or hurricane has not done what the NHC or other experts said they would. Sometimes I think they don't get the memo.
Same here. I love the current track; except for the part over Bermuda, it keeps most of the worst away from people. I don't like the idea of a westward shift at all, but I know the names of all the storms that "didn't get the memo"... lol
18Z GFDL 48 hours


Quoting 1500. MississippiWx:


Yeah, that and backyards.


(did 13 hit puberty? uhoh)
Quoting 1500. MississippiWx:


Yeah, that and backyards.


Backyards are overrated.
Quoting TropicalAnalystwx13:

Spitting gaps is fun. Do it all the time.
I think is heading directly over Puerto Rico ,looking at the Center, moving NNW in the Puerto Rico RAdar doppler......
Quoting 1497. MississippiWx:
Don't forget about our Bay of Campeche disturbance. It has a much better circulation today, although it is still very large. Looks closed on visible loops, but it's obviously void of convection centrally and very broad. Wouldn't surprise me to see convection begin to kick up over the water in the BOC tonight.


Agreed. Obviously a nice spin going on down there. Wouldn't rule this out..
1540. Patrap
Quoting 1535. nrtiwlnvragn:
18Z GFDL 48 hours



? Over by Haiti?
uh huh? 10% to the left of td 7
Quoting 1531. JLPR2:


Not much to report at the moment, light showers and a great sunset.
XD
Doesn't sound like much.Kinda surprised due to the close proximity to P.R at the moment.
Quoting JLPR2:


Not much to report at the moment, light showers and a great sunset.
XD
Yes is the calm before the storm.... all the ants are heading North towards my window as is the center of TD7,,,,,
1546. Kyon5
Quoting 1518. wunderkidcayman:

It jogged N now it moving W so there is your NNW drift it just started its W movement just wait and see if that W movement continues the it can properly be called a W movement if it starts going N then it will remain NW-NNW movement
Right now it's moving north-northwest, and it's expected to continue to do so.  What you are seeing on the radar is most likely a wobble, especially since it's moving at 2 mph. The main direction is NNW for now. We'll see what happens tonight.
1547. GatorWX
Very neat interaction. Should be very interesting to watch it play out further and see what happens.

07 looks quite nice and tidy at this point.

Quoting 1519. stormwatcherCI:
Isn't this an intermediate advisory which would just continue with the info from the last advisory ?
They do update the info, but not the maps.
Is the COC SE of PR? If it is, then the forecasted trayectory through the Mona passage wont be...

Quoting 1541. sporteguy03:

? Over by Haiti?


Yep
1551. Patrap
Quoting 1541. sporteguy03:

? Over by Haiti?


BAM Shallow,

The common outlier all along.

000
ABNT20 KNHC 042339
TWOAT

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 PM EDT WED SEP 4 2013

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

THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON NEWLY FORMED
TROPICAL DEPRESSION SEVEN...LOCATED SOUTH OF PUERTO RICO.

A LARGE AREA OF DISORGANIZED SHOWERS AND THUNDERSTORMS LOCATED TO
THE NORTHEAST OF THE LEEWARD ISLANDS IS ASSOCIATED WITH A SURFACE
TROUGH. ANY DEVELOPMENT OF THIS SYSTEM IS EXPECTED TO BE LIMITED
DUE TO ITS PROXIMITY TO TROPICAL DEPRESSION SEVEN. THIS SYSTEM HAS
A LOW CHANCE...10 PERCENT...OF BECOMING A TROPICAL CYCLONE DURING
THE NEXT 48 HOURS AS IT MOVES NORTHWESTWARD AT 10 TO 15 MPH.
DEVELOPMENT IS NOT EXPECTED AFTER 48 HOURS...AND THIS SYSTEM HAS A
LOW CHANCE...10 PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE
NEXT 5 DAYS.


DISORGANIZED CLOUDINESS AND SHOWERS OVER THE YUCATAN PENINSULA OF
MEXICO AND THE SOUTHWESTERN GULF OF MEXICO ARE ASSOCIATED WITH A
WESTWARD-MOVING TROPICAL WAVE. DEVELOPMENT...IF ANY...WILL BE SLOW
TO OCCUR BEFORE THIS SYSTEM MOVES INLAND ALONG THE COAST OF MAINLAND
MEXICO ON FRIDAY. THIS SYSTEM HAS A LOW CHANCE...20 PERCENT...OF
BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS...AND A LOW
CHANCE...20 PERCENT
...OF BECOMING A TROPICAL CYCLONE DURING THE
NEXT 5 DAYS.

OTHER SYSTEMS WITH FORMATION POTENTIAL BEYOND 48 HOURS...

A TROPICAL WAVE OVER AFRICA IS EXPECTED TO MOVE OVER THE FAR EASTERN
ATLANTIC OCEAN IN A FEW DAYS...AND SOME DEVELOPMENT OF THIS SYSTEM
IS POSSIBLE OVER THE WEEKEND. THIS SYSTEM HAS A LOW CHANCE...NEAR 0
PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48
HOURS...AND A LOW CHANCE...20 PERCENT
...OF BECOMING A TROPICAL
CYCLONE DURING THE NEXT 5 DAYS.

&&

PUBLIC ADVISORIES ON TROPICAL DEPRESSION SEVEN ARE ISSUED UNDER WMO
HEADER WTNT32 KNHC AND UNDER AWIPS HEADER MIATCPAT2.
FORECAST/ADVISORIES ON TROPICAL DEPRESSION SEVEN ARE ISSUED UNDER
WMO HEADER WTNT22 KNHC AND UNDER AWIPS HEADER MIATCMAT2.

FIVE-DAY FORMATION PROBABILITIES ARE EXPERIMENTAL IN 2013. COMMENTS
ON THE EXPERIMENTAL FORECASTS CAN BE PROVIDED AT...

WWW.NWS.NOAA.GOV/SURVEY/NWS-SURVEY.PHP?CODE=ETWO

$$
FORECASTER BRENNAN
Quoting 1522. Grothar:



I'm sorry, I didn't mean to leave anyone out. So here you go:

redwagon - You're completely wrong. :)

I really do have to go now.

And Joe, it was Perry Mason.


I'm actually completely right. Not bragging, but 7 has been sending very strong signals for about 10 days now. I promise I won't gloat.. not my thing. But I will worry.. my thing.
Quoting 1507. TropicalAnalystwx13:
...TROPICAL DEPRESSION DRIFTING NORTH-NORTHWESTWARD...
...EXPECTED TO BECOME A TROPICAL STORM TONIGHT OR TOMORROW...
mountainous islands like PR form their own little mini High ptessure areas at night from the cold air sinking down the mountains.. so this may block/stall it
1555. JRRP
now WNW lol
1556. JLPR2
Quoting 1544. washingtonian115:
Doesn't sound like much.Kinda surprised due to the close proximity to P.R at the moment.


Me too, the system seems to have lost most of its bands and has concentrated almost all of its convection over the circulation. An anular-ish Tropical Depression? XD
Quoting 1526. jascott1967:


So does a drunk camel.
And you know this how????
Quoting 1900hurricane:
07L sure isn't a very large tropical cyclone, especially when one looks at radar.
Yes very small, we wont feel the brunt of the storm until it touches our shores....
1559. SLU
yup
Quoting 1524. stormpetrol:


Latest radar loops suggest an almost due west movement,BTW , yes I'm a westcaster and proud of it :)),also I tell it like I see it!

Lol go man go man go lol
No but in all seriousness yes I agree I see the same thing no Wcasting just saying it like it is

Quoting 1544. washingtonian115:
Doesn't sound like much.Kinda surprised due to the close proximity to P.R at the moment.
Core is not that big. I suppose that's one reason more rain is not expected given the relatively slow movement.
1562. Relix
Not much going on in PR
Quoting sunlinepr:
Is the COC SE of PR? If it is, then the forecasted trayectory through the Mona passage wont be...

Agree, is heading straight towards Puerto Rico might enter near Guayanilla and exit Aguadilla if it continues that NNW track,,but is moving really slow....
Quoting 1543. bigwes6844:
uh huh? 10% to the left of td 7

Exactley.. but put the odds a little higher
1565. GetReal






The last several frames of the radar indicate that 07L has resumed a more true WNW track towards the Se Dominican coast. The current steering maps confirm the flow towards a more general W/WNW motion.
Quoting 1557. BahaHurican:
And you know this how????


I saw one once on a commercial.


This is Strange!
1568. JRRP
Quoting 1549. sunlinepr:
Is the COC SE of PR? If it is, then the forecasted trayectory through the Mona passage wont be...

Centre is actually along the SE corner of the red ball of convection S of PR... I expect it will wobble along to the west overnight. But certainly it seems most of the heavy rainfall will be over you guys...
1570. GatorWX
I found this to be an interesting image. Note the straight lines making a box in central and east FL. Thought it was strange.

Quoting 1522. Grothar:



I'm sorry, I didn't mean to leave anyone out. So here you go:

redwagon - You're completely wrong. :)

I really do have to go now.

And Joe, it was Perry Mason.


Have a good evening Gro!
The low-level and mid-level centers are not quite aligned yet in association with TD Seven. The rotation you're seeing in conjunction with the deepest storms on radar is the mid-level center; the low-level center appears to be ever so slightly southwest of that. The more this deep convection fires, however, the better aligned they will be, especially since the system is nearly stalled and there's very little in the way to disrupt the process.
FROM THE 2000 TWO...
1. A LARGE AREA OF DISORGANIZED SHOWERS AND THUNDERSTORMS LOCATED TO THE NORTHEAST OF THE LEEWARD ISLANDS IS ASSOCIATED WITH A SURFACE TROUGH. ANY DEVELOPMENT OF THIS SYSTEM IS EXPECTED TO BE LIMITED DUE TO ITS PROXIMITY TO TROPICAL DEPRESSION SEVEN.

Why would they (national hurricane center) even bothering mentioning it when it looks like it will be absorbed by td7?
Just curious?
Quoting 1566. jascott1967:


I saw one once on a commercial.
LOL... I actually got an answer!!!

ROTFLOL....
Quoting 1542. Levi32:
Good evening.

Blog update:

Video discussion on Tropical Depression #7
Thank you Levi. Very informative!
Quoting 1567. CaicosRetiredSailor:


This is Strange!
Now... it would be COMPLETELY shocking if the Twave ate the TD...
Obviously, everyone's attention is on td 7, but for me I'm still watching that Boc disturbance
For a potential surprise.
1579. scott39
Does anyone have an idea what will happen to TD7s track if the blob to the E merges with it?
Hmm models that take TD7 into Hispaniola (Haiti)
BAMS BAMM BAMD NAM SHIPS LGEM DSHP

(Dom. Rep.)
CLIP OCD5 LBAR
Quoting 1567. CaicosRetiredSailor:


This is Strange!


Pre-Gab reminds me of Laura ?Finney? from Twin Peaks in her Men In Black role: total control.
1582. tkdaime
hi all just got on so where will td7 go west or ne
Good evening wunder friends, since when did the NHC use google maps overlay for their 5 day projections? Anyways the path looks pretty much set for a passage through the Mona Passage or directly over Puerto Rico and after that a sharp hook to the Northeast and OTS. Not looking like much in the way of any westward movement predicted.

NHC mentioning the wave that the GFS develops into a powerful hurricane in a couple days.

A TROPICAL WAVE OVER AFRICA IS EXPECTED TO MOVE OVER THE FAR EASTERN
ATLANTIC OCEAN IN A FEW DAYS...AND SOME DEVELOPMENT OF THIS SYSTEM
IS POSSIBLE OVER THE WEEKEND. THIS SYSTEM HAS A LOW CHANCE...NEAR 0
PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48
HOURS...AND A LOW CHANCE...20 PERCENT...OF BECOMING A TROPICAL
CYCLONE DURING THE NEXT 5 DAYS.
1585. GatorWX
Quoting 1565. GetReal:






The last several frames of the radar indicate that 07L has resumed a more true WNW track towards the Se Dominican coast. The current steering maps confirm the flow towards a more general W/WNW motion.

Yep

Quoting 1572. TropicalAnalystwx13:
The low-level and mid-level centers are not quite aligned yet in association with TD Seven. The rotation you're seeing in conjunction with the deepest storms on radar is the mid-level center; the low-level center appears to be ever so slightly southwest of that. The more this deep convection fires, however, the better aligned they will be, especially since the system is nearly stalled and there's very little in the way to disrupt the process.

Yep the LLC is SW of MLC I agree with that

I remember in 2005 when a certain storm was predicted for days to go elsewhere and I watch that track for days up until the1100 am update on Friday Aug 26...Even then it was going elsewhere. So I stopped watching because I thought it wasn't coming my way (gulf Coast ms). On the the next advisory the path had changed and my area was in the path but because i had stopped watching someone else had to inform me of the change in path.so no one can be sure what a possible storm will do.
Quoting 1584. Ameister12:
NHC mentioning the wave that the GFS develops into a powerful hurricane in a couple days.

A TROPICAL WAVE OVER AFRICA IS EXPECTED TO MOVE OVER THE FAR EASTERN
ATLANTIC OCEAN IN A FEW DAYS...AND SOME DEVELOPMENT OF THIS SYSTEM
IS POSSIBLE OVER THE WEEKEND. THIS SYSTEM HAS A LOW CHANCE...NEAR 0
PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48
HOURS...AND A LOW CHANCE...20 PERCENT...OF BECOMING A TROPICAL
CYCLONE DURING THE NEXT 5 DAYS.

You can tell they're cautious though. By 5 days the GFS already has a 984mb high end TS/Cat 1 hurricane. They want to make sure this wave isn't going to bust like all the others.

Quoting 1572. TropicalAnalystwx13:
The low-level and mid-level centers are not quite aligned yet in association with TD Seven. The rotation you're seeing in conjunction with the deepest storms on radar is the mid-level center; the low-level center appears to be ever so slightly southwest of that. The more this deep convection fires, however, the better aligned they will be, especially since the system is nearly stalled and there's very little in the way to disrupt the process.
stall = track direction shift.
Quoting 1502. Patrap:
TD 7 knows what day it iz.





Hump day?
Quoting 1556. JLPR2:


Me too, the system seems to have lost most of its bands and has concentrated almost all of its convection over the circulation. An anular-ish Tropical Depression? XD


Been that kind of year with most of the storms.
Well if both the GFS and the ECMWF are to be believed, its going to be another 18 hours before this gets to the Mona passage. So, any observed motion from the radar is nothing but wishful thinking.

For los amigos y amigas in PR and DR - stay safe and dry. Hopefully this does not end up dumping a lot of rain on you.

Catch you all later tonight. Should have moved about 10-12 miles by then :D
Quoting 1589. BahaHurican:
stall = track direction shift.



Track shift how ?
Quoting 1588. MAweatherboy1:

You can tell they're cautious though. By 5 days the GFS already has a 984mb high end TS/Cat 1 hurricane. They want to make sure this wave isn't going to bust like all the others.


That's a smart move. I mentioned a little earlier that the 18z run could potentially be another huge bust.
Quoting 1589. BahaHurican:
stall = track direction shift.

Well, the 8pm AST intermediate advisory did change the direction from northwest to north-northwest. :)
Quoting 1567. CaicosRetiredSailor:


This is Strange!


Reminds me of Doc looking into the microscope and seeing one cell, that of "the thing" obsorbing the dogs cell. The Thing!
07L has a real nice satellite presentation, I would say this definitely has the highest potential of any Atlantic storm so far to become a hurricane, though whether it does is far from certain. If it can build some stronger convection as we head towards DMAX later on then it will really be in good shape.



As usual too much attention is being paid to short term track wobbles. The long term motion has been, is, and will continue to be, NW.
Quoting 1578. RGVtropicalWx13:
Obviously, everyone's attention is on td 7, but for me I'm still watching that Boc disturbance
For a potential surprise.
we not talkin' 'bout it much, but we r stayin' aware... tyvm, mswx.
1599. Patrap
Quoting 1573. HRhurricane:
FROM THE 2000 TWO...
1. A LARGE AREA OF DISORGANIZED SHOWERS AND THUNDERSTORMS LOCATED TO THE NORTHEAST OF THE LEEWARD ISLANDS IS ASSOCIATED WITH A SURFACE TROUGH. ANY DEVELOPMENT OF THIS SYSTEM IS EXPECTED TO BE LIMITED DUE TO ITS PROXIMITY TO TROPICAL DEPRESSION SEVEN.

Why would they (national hurricane center) even bothering mentioning it when it looks like it will be absorbed by td7?
Just curious?


because it has the ability to enhance TD7 ..
Quoting 1589. BahaHurican:
stall = track direction shift.


Even if 7 misses this trough there are 2 more troughs that will sweep it away...
Quoting 1589. BahaHurican:
stall = track direction shift.


And when you stall because you just took on half the mass of a blob East of you, whatever motion you were making is now off the table. A newly large - and deal with it, annular- storm may drift for days, winding up West via simple inertia before digging in and propelling itself poleward.
1603. SRQfl
Quoting 1570. GatorWX:
I found this to be an interesting image. Note the straight lines making a box in central and east FL. Thought it was strange.


Strange indeed...hmmm, nah couldn't be...
Nothing like a 400 lb gorilla on your back.
The little rain field is surprisingly small compared to earlier on the radar. Anyone of you in PR getting major rainfall totals yet??

1605. ncstorm
Interesting video Levi..
04/2345 UTC 16.8N 66.3W T2.5/2.5 07L -- Atlantic
Quoting 1604. Abacosurf:
Nothing like a 400 lb gorilla on your back.
The little rain field is surprisingly small compared to earlier on the radar. Anyone of you in PR getting major rainfall totals yet??

not really
Good afternoon/evening.

I see that 97L has acquired sufficient organization to be classified as the seventh tropical depression of the season. Satellite and radar loops indicate that 07L remains well organized with heavy thunderstorms persisting over the center as well as banding features developing to the east. I say we'll see Gabrielle by late tonight.

1609. GatorWX
Perfect outflow!



Also,



Not as good as earlier in that dept.
Quoting PRweathercenter:
not really
It became very compacted,,, but convection can explode at any minute...
Quoting 1593. weatherlover94:



Track shift how ?
One typical reason for a system to slow is because it's rounding a high or moving into a weakness. The stall in its most general interpretation implies that steering currents are weak.

Quoting 1608. Civicane49:
Good afternoon/evening.

I see that 97L has acquired sufficient organization to be classified as the seventh tropical depression of the season. Satellite and radar loops indicate that 07L remains well organized with heavy thunderstorms persisting over the center as well as banding features developing to the east. I say we'll see Gabrielle by late tonight.


Actually the LLC is just SW of that ball of convection
Quoting 1568. JRRP:

Would be weird of the GFS scenario played out.
Quoting 1604. Abacosurf:
Nothing like a 400 lb gorilla on your back.
The little rain field is surprisingly small compared to earlier on the radar. Anyone of you in PR getting major rainfall totals yet??



hey there
its been raining in cupey, PR for a few days now, at least 24hrs nonstop

this gabriel fellow... has surprised me
rapid intensification
nothing too intense but then again im on the north-northeast metro area

interesting
1615. GatorWX
Quoting 1609. GatorWX:
Perfect outflow!



Also,



Not as good as earlier in that dept.


For Puerto Rico's sake, it may be a very good thing P30 is there! Stealing a lot of potential energy away from a system that is essentially stalled. Upper level conditions are obviously conducive and water is warm.
Quoting 1522. Grothar:



I'm sorry, I didn't mean to leave anyone out. So here you go:

redwagon - You're completely wrong. :)

I really do have to go now.

And Joe, it was Perry Mason.


Hi Gro!

I hope all is well. So what is the prognosis for the TD7 and the wave to its east?
At this slow rate of movement TD7 effects over PR should start in Thanksgiving weekend!!
TXNT28 KNES 050014
TCSNTL

A. 07L (NONAME)

B. 04/2345Z

C. 16.8N

D. 66.3W

E. THREE/GOES-E

F. T2.5/2.5/D1.0/24HRS

G. IR/EIR

H. REMARKS...SYSTEM ORGANIZATION IMPROVED WITH DT=2.5 BASED ON 4/10
BANDING. MET AND PAT ALSO 2.5. STRONGEST CONVECTION NE OF CENTER. FT IS
BASED ON DT.

I. ADDL POSITIONS

NIL


...SWANSON

Link
1619. Patrap
So nobody is taking into consideration the 8pm GFS Track on the weatherUnderground page???? Which has TD7 doing a loop then heading towards the eastern Bahamas??? I though GFS was one of the better models???
AL, 07, 2013090500, , BEST, 0, 167N, 663W, 30, 1008, TD
The wave to the east is really throwing out some impressive convection....
1623. GatorWX
Quoting 1611. BahaHurican:
One typical reason for a system to slow is because it's rounding a high or moving into a weakness. The stall in its most general interpretation implies that steering currents are weak.



I think P30 is also playing a role in that. Weak steering too obviously, but the influence between the two is seemingly having an effect on the forward motion. My $.03.
Quoting 1601. Dman10257:


Even if 7 misses this trough there are 2 more troughs that will sweep it away...
only one more trough left not two.
San Juan still dry.
given the season's slow start...TD7 looks good compared to what has come before it..

at least its something to look at and admire
1627. GatorWX

San Juan still dry.
Quoting 1620. NortheastGuy:
So nobody is taking into consideration the 8pm GFS Track on the weatherUnderground page???? Which has TD7 doing a loop then heading towards the eastern Bahamas??? I though GFS was one of the better models???


apparently not this year...
its SILLY to have a 10% right next to the tropical d seven
Wow, doesn't get much better than this.
Hurricane Celia 2010
Quoting 1630. hurricanes2018:
its SILLY to have a 10% right next to the tropical d seven

Why and how is it silly?
Quoting 1609. GatorWX:
Perfect outflow!



Also,



Not as good as earlier in that dept.


It seems to be merging wight the wave. We should see Gabriel as they merge.
The NHC almost always follows the GFS in terms of track.
Quoting 1604. Abacosurf:
Nothing like a 400 lb gorilla on your back.
The little rain field is surprisingly small compared to earlier on the radar. Anyone of you in PR getting major rainfall totals yet??



Nothing happening in San Juan, we still dry.
Interesting that many pple thought I meant a westward shift, when I was thinking a Nward one... when a storm slows like this, it's often because it's getting to a place where a northern escape is possible. Dman mentioned later troughs, but I think there is a lot riding on this first one, since it's the one likely to pull it up over 20N... after that, a later trough might not be in time to prevent effects along the edge of the WATL...

I'm going with NHC right now, especially given the fact that I have only briefly looked at this system over the last two days. There seems to be enough for now to suggest they have the right track. However, just 100 miles of deviation to the west could cause some rather different impacts in the 3-5 day range.

But we shall see.
Quoting 1633. Articuno:

Why and how is it silly?
I think the 10% is going right into the tropical d seven soon so why have it!
1639. JRRP
what the ...
Quoting 1620. NortheastGuy:
So nobody is taking into consideration the 8pm GFS Track on the weatherUnderground page???? Which has TD7 doing a loop then heading towards the eastern Bahamas??? I though GFS was one of the better models???
GFS has been all over the place this summer... the loop is always a possibility, but I think we mostly want to see conditions closer to the time before we buy it.
Quoting 1623. GatorWX:


I think P30 is also playing a role in that. Weak steering too obviously, but the influence between the two is seemingly having an effect on the forward motion. My $.03.
Agreed. We were talking about this earlier...

I think we sometimes forget that more than one factor can influence a system...
1643. ncstorm
Quoting 1638. hurricanes2018:
I think the 10% is going right into the tropical d seven soon so why have it!


Because some models keep the 850 mb vorticity associated with the wave to the NE of TD07 separate.
Tropical Depression Toraji over Japan.
Quoting 1639. JRRP:
what the ...


LOL at the GFDL.
Quoting 1626. MisterPerfect:
given the season's slow start...TD7 looks good compared to what has come before it..

at least its something to look at and admire


Very charismatic storm... small, pernicious, tenacious. I'd physically analog it to Charley.. once she exits the loading-up dock of the blob to her East phase. I think tracking has to go back to the drawing board once she de-couples from that blob she's feeding on.. she will not be tomorrow what she is right now.
JeffMasters has created a new entry.
CWG mentions front after front.I don't think this is getting anywhere near the east coast.I agree with the NHC's thinking...I see Tigerosee is in the back woods waiting..
Very calm in Sabana Grande, PR. I guess this will change overnight.
Quoting 1637. BahaHurican:
Interesting that many pple thought I meant a westward shift, when I was thinking a Nward one... when a storm slows like this, it's often because it's getting to a place where a northern escape is possible. Dman mentioned later troughs, but I think there is a lot riding on this first one, since it's the one likely to pull it up over 20N... after that, a later trough might not be in time to prevent effects along the edge of the WATL...

I'm going with NHC right now, especially given the fact that I have only briefly looked at this system over the last two days. There seems to be enough for now to suggest they have the right track. However, just 100 miles of deviation to the west could cause some rather different impacts in the 3-5 day range.

But we shall see.


Haha Baha with so many wishcasters on here it's become habitual to think of everyone calling for a track change to want it to head west :)
Quoting 1644. daddyjames:


Because some models keep the 850 mb vorticity associated with the wave to the NE of TD07 separate.
maybe we have TD07 AND INVEST 99L soon.
1654. GatorWX
Quoting 1634. FunnelVortex:


It seems to be merging wight the wave. We should see Gabriel as they merge.


It'll be very neat to see how the "two" react. I really don't know if I'm sure they're just going to merge into one.

800mb



700mb



At least until one really becomes dominant, ie strengthens. Right now, as good as 07L looks, it's not particularly strong and they seem as if they're still very much their own respected entities. That could take some time to occur. For now, it sure seems as if P30 is suppressing the forward motion of 07.
Now



-3 hours




Weakness even further west now. Hmmm. What will that spell for steering ?????
Satellite estimates from both SAB and TAFB yield an intensity of 35kts.

AL, 07, 201309042345, 10, DVTS, CI, , 1680N, 6630W, , 2, 35, 2, , , , , , , , , , , , , , , , , L, SAB, GS, IM, 3, 2525 /////, , , GOES13, LLCC, T, DT=2.5 BO CBND MET=2.5 PT=2.5 FTBO DT

AL, 07, 201309042345, 10, DVTS, CI, , 1690N, 6620W, , 3, 35, 2, , , , , , , , , , , , , , , , , , TAFB, WB, I, 5, 2525 /////, , , GOES13, CSC, T, 0.45 BANDING DT=2.5
Quoting 1645. Skyepony:
Tropical Depression Toraji over Japan.
Glad that didn't last...
Td 7 lost it's convergence again.. deepest to it's ene with the other wave.
Quoting 1570. GatorWX:
I found this to be an interesting image. Note the straight lines making a box in central and east FL. Thought it was strange.



Josh - that straight boundary line you see is the Lake Wales Ridge.Link
Quoting 1655. stormwatcherCI:
Now



-3 hours




Weakness even further west now. Hmmm. What will that spell for steering ?????

Hmm and look at it again did the weakness also pull N a bit
1661. WWPR
Quoting 1651. weathercuco:
Very calm in Sabana Grande, PR. I guess this will change overnight.


Hopefully not too soon, I still need to get home from work.
Quoting 1639. JRRP:
what the ...


The red line (GFS) still looks my golf drive....I'm sticking with it....fore!
AWESOME LIGHTNING SHOW!!!
1665. MahFL
Quoting 1614. serialteg:


..>rapid intensification
nothing too intense but then again im on the north-northeast metro area

interesting


TD7 is NOT rapidly intensifying. The NHC says "GRADUAL STRENGTHENING". Don't alarm people.
07L/TS/G/XX


???? Portend anything?
This is all you need to know, 2 fronts coming down, if the first one doesn't catch it, then the next one will have a chance to catch it, if that one doesn't catch it, then land bound she blows. Simple as ABC 123.



T.C.F.A.
07L/TS/G/CX

1670. luigi18
http://www.nhc.noaa.gov/cyclones/
1671. luigi18
Gaby is here http://www.nhc.noaa.gov/cyclones/
1672. vis0
Quoting 14. Gearsts:
Already with the rain and wind here in Aguadilla PR


Ah, Aguadilla, P.R. my moms home town. Great-grandmother owned ~40% of that land/town.

Eminent domain took 80% of the 40% for political reasons (1800s), sugarcane PLANT (1800s), Airport, HYDRO plants, Prison ETC. great-Grandma was one of the first to free slaves in Puerto Rico the 1800s, hence she paid a great political price.
She sung (how uneducated people communicated then, by singing) how all people under the arms of nature are not born with chains on their arms, feet nor mind so whom am i (her) to put chains anywhere on their arms, legs or thoughts.

My mother / father are from families whom have a long line of "
Shaman or shaymen  (women too)".
 
If you go into el barrio Guerrero sector Muniz from road #2 my 2ND home is the third on the left (it was tourqousie+white when i last painted it in 2010), its being rented by a "friend" of the family for now. i'm told it might look disheveled as no one is up-keeping the area.
BTW I'm a Nuyorican, live in NYC.

Careful in the valleys as there is natural flooding and flooding from reservoirs??? (refuersos???)  that are opened to prevent damage from too much water pressure.
Yup, just saw that on the WU tropical weather page.
1674. luigi18
Quoting 1672. vis0:
in coloso?
After apparently reforming it center this morning over Vieques island, TD Gabrielle decided that the south is better than the east. The reformed center spin off to the NE and again, the original center resurfaced to south of Ponce, almost the same spot it was clear at 5AM. Salsa dancing you can go either on 1 (dancing to the side) or 2 (dancing to the front and back). She loves #2 Salsa of Puerto Rico, the best in the world!

I suspected something since I have not been able to follow-up the storm on the radar for the last 2 hours. I was working on the field. I noticed that rain outer bands were returning to the south of my position. That will mean that the center is almost at the south of my position. Rain has been pouring on SE and South Central parts of the island, North has been more dried today.

Anyhow, appears that if it wraps with remains of the wave to our east, it may not be as strong as it looks this morning since the spinning off of the center that tried to form over Vieques, appears to be pulling the rain with it. Maybe, we may not see the 10 inches of rain.