Ed Dunham
Former Meteorologist & CFHC Forum Moderator (Ed Passed Away on May 14, 2017)
Reged:
Posts: 2565
Loc: Melbourne, FL
|
|
12:30 PM EDT Update 5 September 2013
Gabrielle has been downgraded to a depression, and her prospects look uncertain, at best.
Tropical Storm Warnings have been discontinued.
Ciel
10:45 PM EDT Update 4 September 2013
Tropical Storm Gabrielle has formed south of Puerto Rico. Tropical Storm Warnings are up for all of Puerto Rico and eastern parts of the Dominican republic.
Land interaction and other factors will likely keep Gabrielle a Tropical Storm, and the forecast track keeps it well east of the mainland US.
3:45 PM EDT Update 4 September 2013
After weeks of little activity in the tropics the wave southeast of Puerto Rico, 97L looks to be giving it a go for organization and may become a depression or storm tonight or early tomorrow.
Those in Puerto Rico and the Virigin Islands (and other nearby islands) will likely see heavy rainfall and stormy conditions. Most models keep the system well east of the US beyond this.
Recon is currently investigating the area, and the state and existance of the low level circulation center is what will likely be the determining if this is upgraded tonight or not. Based on what recon has found so far, it could be upgraded sooner rather than later.
Original Update
After traveling across the tropical Atlantic for over a week, a tropical wave attained better organization on Saturday and was designated as Invest 97L. Although conditions are currently less than ideal for near-term development, in a few days, as the system moves closer to the Greater Antilles, windshear will decrease and the chances for additional development should increase. This will likely be a slow moving and slow developing system.
ED
Caribbean Islands Weather Reports
|
danielw
Moderator
Reged:
Posts: 3525
Loc: Hattiesburg,MS (31.3N 89.3W)
|
|
Both the USAFR Hurricane Hunters and NASA's two Global Hawks are tasked to fly 97L over the next few days.
Notice the Tropical Depression notation in the tasking on Day 2.
WEATHER RECONNAISSANCE FLIGHTS
CARCAH, National Hurricane Center, MIAMI, FL.
1015 AM EDT MON 02 SEPTEMBER 2013
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
VALID 03/1100Z TO 04/1100Z SEPTEMBER 2013
TCPOD NUMBER.....13-093
I. ATLANTIC REQUIREMENTS
1. SUSPECT AREA (CARIBBEAN)
FLIGHT ONE -- TEAL 70
A. 03/2100Z
B. AFXXX 01DDA INVEST
C. 03/1500Z
D. 16.0N 63.0W
E. 03/2030Z TO 03/2330Z
F. SFC TO 10,000 FT
2. OUTLOOK FOR SUCCEEDING DAY: FIX MISSION @ 04/2100Z NEAR
19N 67W IF SYSTEM DEVELOPS.
3. REMARKS: THE NASA 871 GLOBAL HAWK WILL FLY A 24-HOUR RESEARCH
MISSION OVER THIS SYSTEM
A. NASA 871 TAKE-OFF: 03/1100Z
B. STORM/AREA OF INTEREST: DEPRESSION 97L-
C. DEPARTURE WFF: 1100Z, 03 SEP
D. MISSION DURATION: 24H 00M
E. IP: 1500Z, 03 SEP; 25.0 N, 68.0 W
F. EP: 0600Z, 4 SEPT; 25.0 N, 68.0 W
G. ON-STATION DURATION: 15H 00M
H. ETA WFF: 1100Z, 04 SEPT
I. DROPSONDES DEPLOYED: 0, NO SONDE SYSTEM
J. ALTITUDE: 55,000 TO 65,000 FT
K. PATTERN: RACE TRACK ACROSS REGION OF TD
CIRCULATION IN BOX BOUNDED BY 25.0N 68.0W
17.0N 68.0W, 14.0N 55.0W, 19.0N 52.0W
FOLLOWED BY BUTTERFLY WITHIN REGION OF
CONVECTION ~ 200 NM RADIUS FROM 18.0N 67.5W
4. OUTLOOK FOR SUCCEEDING DAY- BACK TO BACK GH MISSIONS:
A. NA871 LANDING, 1100 Z, 04 SEP
B. NA872 TAKE OFF 1500Z, 04 SEP
|
scottsvb
Weather Master
Reged:
Posts: 1184
Loc: fl
|
|
Where is the Radar loop time lapse out of Martinique......(sorry for sp) I wish you guys would post it every time there is something coming through the islands
|
typhoon_tip
Meteorologist
Reged:
Posts: 576
|
|
Climatologically, developing tropical cyclones tend to have difficulty passing through the latitude and longitude that 97L currently is ... TPC is citing dry air at mid levels as the culprit for stymied development, this time, but there are other reasons why TCs have difficulties in that region of Caribbean Sea. In short ...if dry air is the only problem, this feature has a better prospect.
The feature looked more impressive on IR imagery for a couple of days prior to entering the eastern Caribbean. However, now more than ever it has acquired a more obvious cyclonic turning to CU and CB clouds, despite there being less overall convective structures. The deep layer profiles of the atmosphere look to remain conducive to further development.
TPC has again upped the hashed region to orange, or medium chance for intensification. There may be some interference by land as this system [probably] turns more NW and then has to pass over the PR archipelago.
John
Edited by typhoon_tip (Tue Sep 03 2013 08:33 PM)
|
MichaelA
Weather Analyst
Reged:
Posts: 944
Loc: Pinellas Park, FL
|
|
Much more circular in appearance this morning SE of Puerto Rico, but there is still a large area of convection just East of the Lesser Antilles. As states, interaction with PR and Hispaniola could be inhibiting to further or rapid development. Just keeping a wary eye on this for now. Long range PR radar does not indicate a closed LLC, though.
--------------------
Michael
PWS
Edited by MichaelA (Wed Sep 04 2013 03:29 PM)
|
Fairhopian
Weather Watcher
Reged:
Posts: 26
Loc:
|
|
Looking at the long range radar out of Puerto Rico, it appears that we may have a closed circulation, with the movement at the center being mostly westward. Anyone concur?
|
doug
Weather Analyst
Reged:
Posts: 1006
Loc: parrish,fl
|
|
The area to the east and northeast has been catching up and the 2 p.m.TD takes note and states this area will merge with the developing system. This is confirmed by satellite imagery. The question now is will a definite LLC emerge and take over, or will it remain disorganized until it enters the SW ATL. The Shortwave IR would suggest a center somewhere near 16N and 64.5 W, IMO.
--------------------
doug
Edited by doug (Wed Sep 04 2013 06:14 PM)
|
cieldumort
Moderator
Reged:
Posts: 2305
Loc: Austin, Tx
|
|
Recon is flying through 97L now and is presently verifying westerly winds. It's possible we see an upgrade today, and also equally possible that we do not. Most likely, 's decision will hang on how well defined the LLC is, given that there is marginal convection .. earlier in the week we had a closed circulation with associated shower and thunderstorm activity, at times abundant, but the circulation was broad, and ultimately opened back up more or less far too quickly to count. Then the showers and storms fell apart in rapid succession.
Lowest pressures so far being found appear to be about 1010mb, with winds generally at or below 25 knots.
Edit: Latest odds given by at 1:59PM EDT were 50%, but closer inspection of the most recent passes (recon is now flying through the southern portions of 97L), coupled with high res satellite loops, leads me to believe the chances for an upgrade today are probably closer to 75%.
Edited by cieldumort (Wed Sep 04 2013 06:29 PM)
|
MikeC
Admin
Reged:
Posts: 4544
Loc: Orlando, FL
|
|
Last observation from recon suggests it may have found a center, with the system like it is, it may be named/numbered at 5PM. If I were to bet, I'd say straight to a named system. (Gabriella)
A few more passes from recon will really determine one way or the other, if it doesn't happen at 5PM, before the end of the night is still fairly likely.
|
MikeC
Admin
Reged:
Posts: 4544
Loc: Orlando, FL
|
|
The Automated Tropical Cyclone Forecasting System (ATCF) triggered a renumber, so it looks like TD#7 or Gabriella at 5PM is extremely likely. Those in Puerto Rico and the surrounding islands, heads up.
Beyond that it looks like it will stay well east of the US mainland.
|
typhoon_tip
Meteorologist
Reged:
Posts: 576
|
|
And as other's have noted, the appearance of a central axis or rotation was hinted by base-reflective/radar; now that has become more clearly defined ... literally just over the last hour of animation.
|
doug
Weather Analyst
Reged:
Posts: 1006
Loc: parrish,fl
|
|
Looks likely based on the convection firing on the west side of the apparent center, and the beginning of a tap on the moisture from the system to the NE on the north side. This my very well pop today. It will be interesting to see how much influence that other system will have. Some have said it would siphon off the energy from the system, but I think it will be the opposite.
--------------------
doug
|
Hawkeyewx
Weather Analyst
Reged:
Posts: 99
|
|
The surface flow may not be exceptionally organized yet(~1010 mb is fairly weak), but apparently it's enough to upgrade it. There is certainly a nice, fresh convective blowup near the center, which is also aiding the development of mid-level spin.
|
typhoon_tip
Meteorologist
Reged:
Posts: 576
|
|
Depression designated ...
16.5N 66.2W
30kts, movement WNW, 9mph.
Interestingly, TPC moves the cyclone through the Mona Passage, between PR and the DR. That's actually about 60 nautical miles (less Isle of De Mona) of distance there, and could easily allow the the core of this thing an unimpeded transit through the archipelago.
Edited by typhoon_tip (Wed Sep 04 2013 09:08 PM)
|
typhoon_tip
Meteorologist
Reged:
Posts: 576
|
|
When I first looked at TD 7, three hours ago on the San Juan base reflectivity, the system was turning cyclonically overall, but the exact center of rotation was hard to pin-point.
Not the case anymore. In fact, it has a dense core of deep convection collocated with a very identifiable and singular axis of rotation. It even has what looks like a spiral band on the southern arc. And, in total, it is spinning faster.
I don't think this system has any intention of hanging out in TD status for very long. Ample oceanic heat content, superb outflow at high altitudes ... and TPCs track is through the Mona Passage, which is obviously not over a mountainous island.
|
ralphfla
Weather Watcher
Reged:
Posts: 26
|
|
You can tell when it has been a slow season when a A Depression that is going to spin back out to sea most likely and not become anything gets this much attention lol
|
typhoon_tip
Meteorologist
Reged:
Posts: 576
|
|
Quote:
You can tell when it has been a slow season when a A Depression that is going to spin back out to sea most likely and not become anything gets this much attention lol
It has been a slower season than many, including the formal prediction agencies, thought it would be, so far... Things can blossom quickly. The season doesn't end until Dec 1. There is plenty of time for a flurry of activity to transpire.
Although the various models do take would-be Gabrielle polarward in a hurry, there are contingencies to that plan that need be considered.
For one, there is a powerful disturbance that may very well be on a developmental curve of its own, not more than a few hundred miles NE of the TD 7. This feature, if it does develop, will likely impact the track of Gabrielle, and do so in unknown ways -- we certainly cannot entrust too much credence to the guidance(s) beyond just 3 days from now given any potential interaction between these features.
|
Random Chaos
Weather Analyst
Reged:
Posts: 1024
Loc: Maryland
|
|
San Juan radar is showing a good band about 30 miles off-shore south of the island, closest points to the band are Guayama and Jauca. Nothing significant closer than that band. IR is showing a very tight, strong circulation.
Looks like the storm just got upgraded to Gabrielle. Nothing from yet, but has already changed it's name. Edit: 15 minutes later, still nothing from . Could be planned for 11pm.
--
Edit: San Juan radar has been upgraded to Dual-Pol radar. Hydrometer classification out of that capability is showing a large amount of possibly hail producing areas in the band just south of Puerto Rico. In the attached image, red indicated hail.
Edited by Random Chaos (Thu Sep 05 2013 02:03 AM)
|
Ed Dunham
Former Meteorologist & CFHC Forum Moderator (Ed Passed Away on May 14, 2017)
Reged:
Posts: 2565
Loc: Melbourne, FL
|
|
I don't find anything humorous about a slow-moving system that could produce up to 10 inches of rain in the mountains of Puerto Rico and the Dominican Republic with the flash flooding that would result from those heavy rains. Flippant posts have no place on this site.
ED
|
Random Chaos
Weather Analyst
Reged:
Posts: 1024
Loc: Maryland
|
|
St. Croix has gotten the most rain so far, with a narrow region of its SW coast showing Doppler estimates of 4-6" of rain, though most of the island is showing around 2". There is a large region over open water that has seen 10-11"+ of rainfall 55-80 miles SSE of Puerto Rico and 45-60 miles SW of St. Croix. St. Croix is under a flash flood warning.
System looks fairly good on radar, still has a lot of development to do, but it's quite small. Question is, with its proximity to the mountains of Puerto Rico, whether this will disrupt its development at all.
|
Previous
Index
Next
Threaded
Edit
Reply
Quote
