ATL: GABRIELLE - Post-Tropical - Discussion

[WeatherEmperor]

NHC still has it as a TD at 11pm advisory tgat just came out. Interesting.....

Tropical Depression Eight Advisory Number 2
NWS National Hurricane Center Miami FL AL082019
1100 PM AST Tue Sep 03 2019


...DEPRESSION EXPECTED TO STRENGTHEN TO A TROPICAL STORM ON WEDNESDAY...



SUMMARY OF 1100 PM AST...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...19.1N 32.8W ABOUT 615 MI...995 KM WNW OF THE CABO VERDE ISLANDS MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H PRESENT MOVEMENT...NW OR 320 DEGREES AT 8 MPH...13 KM/H MINIMUM CENTRAL PRESSURE...1006 MB...29.71 INCHES



WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.



DISCUSSION AND OUTLOOK
----------------------
At 1100 PM AST (0300 UTC), the center of Tropical Depression Eight was located near latitude 19.1 North, longitude 32.8 West. The depression is moving toward the northwest near 8 mph (13 km/h), and this general motion is expected to continue through Friday with an increase in forward speed late in the week.

Maximum sustained winds are near 35 mph (55 km/h) with higher gusts. Some slow strengthening is possible over the next few days, and the depression is expected to become a tropical storm on Wednesday.

The estimated minimum central pressure is 1006 mb (29.71 inches).



HAZARDS AFFECTING LAND
----------------------
None



NEXT ADVISORY
-------------
Next complete advisory at 500 AM AST.

$$ Forecaster Latto



Sent from my iPhone using Tapatalk

[Hypercane_Kyle]

Yea, hate it when they go with an upgrade on the ATCF and then new data comes in by the next advisory to prove it wrong. Proves they don't pad stats, at the very least.

[AnnularCane]

Yea, hate it when they go with an upgrade on the ATCF and then new data comes in by the next advisory to prove it wrong. Proves they don't pad stats, at the very least.

True, but what a letdown! Oh well, maybe next advisory.

[ROCK]

OTS:::next??

[Hammy]

"Gabrielle on next advisory" take 2.

[HurricaneAndre2008]

000
WTNT23 KNHC 040853
TCMAT3

TROPICAL STORM GABRIELLE FORECAST/ADVISORY NUMBER 3
NWS NATIONAL HURRICANE CENTER MIAMI FL AL082019
0900 UTC WED SEP 04 2019

THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.

TROPICAL STORM CENTER LOCATED NEAR 19.6N 33.6W AT 04/0900Z
POSITION ACCURATE WITHIN 30 NM

PRESENT MOVEMENT TOWARD THE NORTHWEST OR 310 DEGREES AT 9 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 1005 MB
MAX SUSTAINED WINDS 35 KT WITH GUSTS TO 45 KT.
34 KT....... 0NE 0SE 0SW 80NW.
12 FT SEAS.. 60NE 0SE 0SW 60NW.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 19.6N 33.6W AT 04/0900Z
AT 04/0600Z CENTER WAS LOCATED NEAR 19.4N 33.4W

[cycloneye]

Tropical Storm Gabrielle Discussion Number 3
NWS National Hurricane Center Miami FL AL082019
500 AM AST Wed Sep 04 2019

A late-arriving ASCAT-C scatterometer pass revealed peak surface
winds of 33 kt in the northwestern quadrant, and satellite imagery
since then indicates a marked increase in the deep convection,
albeit sheared to the northeast of the well-defined low-level center
noted in the scatterometer data. Based on these wind data and a
satellite intensity estimate of T2.5/35 kt from TAFB and UW-CIMSS
ADT, the depression has been upgraded to Tropical Storm Gabrielle,
the seventh named storm of the 2019 Atlantic hurricane season.

The initial motion is 310/09 kt. The initial position was adjusted
slightly to the southwest of the previous positions based on the
aforementioned scatterometer data. This has resulted in the new
forecast track being shifted a little to the left of the previous
advisory track at all forecast times. For the next 5 days,
Gabrielle is forecast to move generally northwestward toward a break
in the Bermuda-Azores high pressure ridge located between 40W-50W
longitude. The official forecast track lies close to a blend of the
tightly packed consensus models TVCN, TVCX, and NOAA-HCCA.

During the entire forecast period, Gabrielle is forecast to remain
in a marginally conducive environment characterized by moderate
southwesterly vertical wind shear of 15-20 kt, SSTs of 26-27 deg C,
and dry mid-level air with humidity values less than 50 percent. As
a result, only slight strengthening is forecast through 72 hours.
The new NHC intensity forecast is similar to the previous advisory,
and closely follows the HCCA consensus intensity model.

FORECAST POSITIONS AND MAX WINDS

INIT 04/0900Z 19.6N 33.6W 35 KT 40 MPH
12H 04/1800Z 20.3N 34.4W 40 KT 45 MPH
24H 05/0600Z 21.1N 35.3W 40 KT 45 MPH
36H 05/1800Z 22.1N 36.4W 45 KT 50 MPH
48H 06/0600Z 23.4N 37.7W 45 KT 50 MPH
72H 07/0600Z 27.5N 41.0W 50 KT 60 MPH
96H 08/0600Z 31.5N 44.5W 50 KT 60 MPH
120H 09/0600Z 35.5N 47.2W 50 KT 60 MPH

$$
Forecaster Stewart

[plasticup]

OTS:::next??

I think we are all in the mood for a nice fish after this last week.

[AnnularCane]

There's my Gabbie. Thank you ASCAT!

[cycloneye]

Tropical Storm Gabrielle Discussion Number 4
NWS National Hurricane Center Miami FL AL082019
1100 AM AST Wed Sep 04 2019

Gabrielle appears better organized on satellite imagery
this morning with the low-level center moving a little more
underneath the convection. In addition, a large curved band has
become better defined in the northern semicircle. The initial wind
speed is increased to 45 kt, which is consistent with a
just-received ASCAT-C pass of 40-45 kt.

The initial motion estimate is 320/8. For the next 5 days,
Gabrielle is forecast to move generally northwestward toward a break
in the Bermuda-Azores high pressure ridge located between 40W-50W
longitude. An increase in forward speed in a few days is expected
due to the gradient between an upper-level low to the west and the
ridge to the northeast. The official forecast track lies slightly to
the east of the previous forecast in the short term, and then is
very close to the previous NHC track in days 3 to 5.

Gabrielle is expected to remain in a marginal environment during the
next 2 to 3 days, with moderate southerly to southwesterly wind
shear, low values of mid-level relative humidity and SSTs near
26-27C. No change in wind speed is predicted during the first two
days. Thereafter, some strengthening is possible as Gabrielle moves
on the northeast side of the upper-level low concurrent with the
cyclone moving over warmer water. This is a typical situation for
intensification, so the forecast wind speed is raised slightly at
days 4-5. The intensity forecast is fairly consistent with the bulk
of the typically reliable intensity models.


FORECAST POSITIONS AND MAX WINDS

INIT 04/1500Z 20.5N 33.8W 45 KT 50 MPH
12H 05/0000Z 21.0N 34.5W 45 KT 50 MPH
24H 05/1200Z 21.9N 35.6W 45 KT 50 MPH
36H 06/0000Z 23.1N 36.9W 45 KT 50 MPH
48H 06/1200Z 24.6N 38.4W 45 KT 50 MPH
72H 07/1200Z 28.6N 41.7W 50 KT 60 MPH
96H 08/1200Z 32.5N 45.5W 55 KT 65 MPH
120H 09/1200Z 36.5N 47.5W 55 KT 65 MPH

$$
Forecaster Blake/Hagen

[Hurricane Jed]

Thank goodness this will be a fish.

[Kazmit]

Thank goodness this will be a fish.

Shouldn’t get too strong anyway.

[Abdullah]

Expected to become a hurricane as of 5:00 P.M. 09/04/2019

000
WTNT43 KNHC 042031
TCDAT3

Tropical Storm Gabrielle Discussion Number 5
NWS National Hurricane Center Miami FL AL082019
500 PM AST Wed Sep 04 2019

Recent microwave data suggest that Gabrielle continues to gradually
become better organized, and the last few GOES-16 images show a
convective burst forming over the center. The initial intensity is
estimated at 45 kt based on the Dvorak number from TAFB and an
earlier ASCAT pass from this morning, but it's possible that this
intensity estimate may be conservative. The storm could intensify
a little more in the short-term, but overall it is expected to
remain in a marginal environment during the next couple of days,
characterized by moderate southerly to southwesterly wind shear, low
values of mid-level relative humidity and SSTs near 26-27C. Little
overall change in strength is predicted during the next two days.
Thereafter, some strengthening is likely as Gabrielle moves on the
northeastern side of an upper-level low into a lower shear region,
at the same time the cyclone moves over warmer water. The new NHC
intensity forecast shows Gabrielle reaching hurricane strength in
about 5 days, which is consistent with the latest HWRF, NOAA
corrected-consensus and COAMPS-TC models.

The initial motion is estimated at 325/8. For the next 5 days,
Gabrielle is forecast to move generally northwestward toward a break
in the Bermuda-Azores high pressure ridge. An increase in forward
speed is expected due to the gradient between an upper-level low to
the west and the ridge to the northeast. The latest models have
shifted a little to the west for the point of recurvature in about 5
days, and the official forecast splits the difference between the
previous NHC forecast and the latest various consensus models in the
day 4 to 5 time period.


FORECAST POSITIONS AND MAX WINDS

INIT 04/2100Z 21.0N 34.0W 45 KT 50 MPH
12H 05/0600Z 21.7N 34.6W 50 KT 60 MPH
24H 05/1800Z 22.8N 35.8W 50 KT 60 MPH
36H 06/0600Z 24.2N 37.4W 45 KT 50 MPH
48H 06/1800Z 26.1N 39.1W 45 KT 50 MPH
72H 07/1800Z 30.0N 43.2W 50 KT 60 MPH
96H 08/1800Z 33.0N 47.5W 55 KT 65 MPH
120H 09/1800Z 36.5N 48.5W 65 KT 75 MPH

$$
Forecaster Blake/Hagen

[Hammy]

They're going to bust hard with that intensity forecast. There's no model support for much intensification, nor are conditions very favorable in the eastern half of the Atlantic right now.

[Do_For_Love]

SSTs don't look bad in that area, at least...

https://www.nhc.noaa.gov/tafb/sst_loop/14_atl.png

[Abdullah]

:uarrow: They're going to bust hard with that intensity forecast. There's no model support for much intensification, nor are conditions very favorable in the eastern half of the Atlantic right now.

I mean, they did explain why they raised it - and they've got support from the HWRF.

[supercane4867]

FORECAST POSITIONS AND MAX WINDS

INIT 05/0300Z 21.5N 34.4W 45 KT 50 MPH
12H 05/1200Z 22.4N 35.2W 45 KT 50 MPH
24H 06/0000Z 23.7N 36.6W 45 KT 50 MPH
36H 06/1200Z 25.4N 38.3W 45 KT 50 MPH
48H 07/0000Z 27.3N 40.2W 45 KT 50 MPH
72H 08/0000Z 30.8N 44.6W 55 KT 65 MPH
96H 09/0000Z 34.0N 48.0W 65 KT 75 MPH
120H 10/0000Z 37.5N 48.0W 65 KT 75 MPH

Now forecasted to become a hurricane

[Buck]

No longer forecast to become a hurricane.

[EquusStorm]

Really struggling this morning. Shear isn't making life easy for the LLC.

[Hurricane Jed]

She’s looking pretty exposed right now.