ATL: FIONA - Post-Tropical - Discussion

[Kingarabian]

Atlantic Ocean dry air is downright nasty...

[LarryWx]

Wow this is still a TS?

Gator,
Do you think a weakening would mean a track further SW than what is projected or would it not affect the track much in this case?

[Kazmit]

Fiona's struggling. Hopefully it can get it's act together after it leaves this unfavourable area or it will be quite a disappointing storm.

[p1nheadlarry]

Atlantic Ocean dry air is downright nasty...

Along with the larger size with more potential heat, one of the reasons the WPAC creates more monster storms.

[Blown Away]

Fiona's struggling. Hopefully it can get it's act together after it leaves this unfavourable area or it will be quite a disappointing storm.

Is there a time when an Atlantic system leaves an unfavorable area??

[blp]

18z HWRF weaker and further west. The trend continues.

[JaxGator]

Fiona's struggling. Hopefully it can get it's act together after it leaves this unfavourable area or it will be quite a disappointing storm.

Is there a time when an Atlantic system leaves an unfavorable area??

Earl. And we know how that storm turned out.

[JaxGator]

The weaker and west trend could be a bad thing as it might encounter more favorable conditions but hard to tell atm.

[gatorcane]

18z HWRF never gets this above 20N

[p1nheadlarry]

Little bursts of convection shows at least Fiona is still defined at the surface.

[JaxGator]

Little bursts of convection shows at least Fiona is still defined at the surface.

Yep, she's hanging in there.

[cycloneye]

BULLETIN
TROPICAL STORM FIONA ADVISORY NUMBER 5
NWS NATIONAL HURRICANE CENTER MIAMI FL AL062016
1100 PM AST WED AUG 17 2016

...FIONA TURNS WEST-NORTHWESTWARD WITH NO CHANGE IN STRENGTH...


SUMMARY OF 1100 PM AST...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...15.5N 39.0W
ABOUT 995 MI...1605 KM W OF THE CABO VERDE ISLANDS
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...WNW OR 300 DEGREES AT 16 MPH...26 KM/H
MINIMUM CENTRAL PRESSURE...1006 MB...29.71 INCHES



TROPICAL STORM FIONA DISCUSSION NUMBER 5
NWS NATIONAL HURRICANE CENTER MIAMI FL AL062016
1100 PM AST WED AUG 17 2016

For a time late this afternoon, it seemed that Fiona might lose all
its deep convection. However, a new burst developed around 2300 UTC
and has persisted since that time. An 0026 UTC ASCAT-B pass
revealed that the cyclone is still producing a small area of
tropical-storm-force winds, and the intensity remains 35 kt.

Fiona has a tough road ahead. Vertical shear right now is
relatively low, but it is expected to begin increasing within the
next 24 hours and then become belligerent out of the southwest by
days 3 and 4. In addition, the cyclone is surrounded by dry air,
and any negative impacts that the dry air is already having on the
convection is likely to be compounded once the shear increases in a
few days. With the exception of the GFDL, which makes Fiona a
hurricane by the end of the forecast period, the rest of the
intensity models respond to the unfavorable environment by showing
relatively little strengthening. The NHC forecast follows this same
thinking, and it shows Fiona only modestly strengthening during the
next 36 hours, with some weakening probable by day 3. Based on the
latest intensity guidance, the new NHC forecast has been adjusted
downward from the previous forecast, but it still lies above the
consensus at most forecast times.

The recent ASCAT data helped to fix the center, and the initial
motion estimate is now west-northwestward, or 300/14 kt. A break
in the mid-tropospheric ridge to the north of Fiona is expected to
to migrate westward during the next few days, but the cyclone's
shallow nature is expected to help maintain a west-northwestward
motion for much of the forecast period. The bulk of the track
models are tightly clustered on such a heading. However, the GFDL
(which makes Fiona hurricane) shows a sharp northward turn, while
the HWRF (which essentially shows no intensification) takes a much
more southern track. Since these two scenarios appear to cancel
each other out, the NHC official forecast closely follows the
consensus models, requiring a westward adjustment to the previous
forecast.

FORECAST POSITIONS AND MAX WINDS

INIT 18/0300Z 15.5N 39.0W 35 KT 40 MPH
12H 18/1200Z 16.3N 40.4W 35 KT 40 MPH
24H 19/0000Z 17.1N 41.9W 40 KT 45 MPH
36H 19/1200Z 17.8N 43.5W 45 KT 50 MPH
48H 20/0000Z 18.6N 45.2W 45 KT 50 MPH
72H 21/0000Z 20.6N 49.1W 40 KT 45 MPH
96H 22/0000Z 22.5N 53.0W 40 KT 45 MPH
120H 23/0000Z 24.5N 57.0W 40 KT 45 MPH

$$
Forecaster Berg

[gatorcane]

Fiona has made a turn more to the WNW as the NHC has stated in the latest advisory. Loop below shows the subtle turn:

http://rammb.cira.colostate.edu/ramsdis ... display=12

[NDG]

Latest ASCAT

[hurricanes1234]

From the 11 pm discussion:

Fiona has a tough road ahead. Vertical shear right now is
relatively low, but it is expected to begin increasing within the
next 24 hours and then become belligerent out of the southwest by
days 3 and 4.

Belligerent shear


I love their choice of words describing the unfavourable upper-level regime to come.

[Socalhurcnegirl227]

From the 11 pm discussion:

Fiona has a tough road ahead. Vertical shear right now is
relatively low, but it is expected to begin increasing within the
next 24 hours and then become belligerent out of the southwest by
days 3 and 4.

Belligerent shear


I love their choice of words describing the unfavourable upper-level regime to come.

go home shear....your drunk lol

[p1nheadlarry]

From the 11 pm discussion:

Fiona has a tough road ahead. Vertical shear right now is
relatively low, but it is expected to begin increasing within the
next 24 hours and then become belligerent out of the southwest by
days 3 and 4.

Belligerent shear


I love their choice of words describing the unfavourable upper-level regime to come.

go home shear....your drunk lol

Shear: You talkin'a me?

Fiona is barely hanging on to TS status, though the most recent ASCAT pass looks a bit better than the one before, more ~30 kt vectors on the northern side. Their initial 50 kt forecast a bit on the high end in hindsight. Dry air acted fast this evening.

[LarryWx]

Fiona has made a turn more to the WNW as the NHC has stated in the latest advisory. Loop below shows the subtle turn:

http://rammb.cira.colostate.edu/ramsdis ... display=12

Interesting, gator. The prior advisory's initial location was 15.1 N, 37.8 W and its first projection point was 16.0 N, 39.0 W as of 2 AM EDT tonight. However, at 11 PM EDT, it had already reached 39.0 W while it was only up to 15.5 N. So, it essentially moved north a little less than half of how much was projected by the time it reached 39.0 W. Let's see whether or not SW corrections continue down the road.

[Alyono]

0Z MU does an about face and shifts east and makes this a hurricane

[Alyono]

cmc cuts about 25 new inlets in the Outer Banks as a powerful hurricane