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07-10-2019, 19:00   #151
Gaoth Laidir
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I started a thread on Hagibis here but at the moment there looks to be little chance of it affecting the match.
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07-10-2019, 19:02   #152
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#Hagibis

No recon, so we don't know the wind speeds

https://twitter.com/SimonStormRider/...405339649?s=19
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11-10-2019, 20:05   #153
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The Nor-easter that's been churning off the New England coast the past few days has developed into Subtropical Melissa this afternoon. It's not expected to last long.

Quote:
NWS National Hurricane Center Miami FL AL142019
1100 AM AST Fri Oct 11 2019

...NOR'EASTER CENTERED SOUTHEAST OF NEW ENGLAND BECOMES A
SUBTROPICAL STORM...
...CHANGE IN STORM STATUS DOES NOT CHANGE EXPECTED IMPACTS FROM WIND
AND COASTAL FLOODING ALONG PORTIONS OF THE MID-ATLANTIC COAST AND
SOUTHEASTERN NEW ENGLAND...


SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...38.5N 69.6W
ABOUT 190 MI...300 KM S OF NANTUCKET MASSACHUSETTS
MAXIMUM SUSTAINED WINDS...65 MPH...100 KM/H
PRESENT MOVEMENT...SSW OR 200 DEGREES AT 3 MPH...6 KM/H
MINIMUM CENTRAL PRESSURE...995 MB...29.39 INCHES
Quote:
NWS National Hurricane Center Miami FL AL142019
1100 AM AST Fri Oct 11 2019

Convection increased near the center of the nor'easter centered
southeast of New England overnight. First-light visible satellite
imagery briefly showed an eye-like feature before the convection
around the immediate center began to weaken. However, a large
convective band still persists over the northern semicircle, and
this structure indicated the system has transitioned to a
subtropical cyclone. The latest Hebert-Poteat classification from
TAFB indicates an initial intensity of 55 kt, and this is also
supported by an earlier scatterometer overpass showing a large area
of winds near 50 kt in the northwest quadrant.

Melissa is currently located underneath an upper-level trough,
resulting in a light shear environment. This trough will begin to
lift northeastward later today, and strong upper-level westerlies
should begin to affect the storm by tonight. This pattern is
expected to cause a weakening trend, and Melissa is forecast to
become post-tropical by Saturday night. The post-tropical cyclone is
then expected to be absorbed by an approaching front in 3 to 4 days.

Melissa is currently embedded in weak steering flow under the upper-
level trough, and little net motion is expected today. Later
tonight, an approaching mid-latitude trough currently crossing
the upper Midwest will begin to force an east-northeastward
motion at a faster forward speed. This motion will continue until
the cyclone is absorbed by the cold front. The NHC track forecast is
closest to the ECMWF ensemble mean.

Ongoing hazards from wind and coastal flooding will continue be
covered by non-tropical products from local National Weather Service
forecast offices.

Gale-force winds that extend well northeastward of Melissa into the
central Atlantic that are not included in the wind radii, since they
are associated with a frontal boundary.

Key Messages:

1. While the nor'easter centered southeast of New England has become
Subtropical Storm Melissa, the expected magnitude of wind and
coastal flooding impacts along portions of the U.S. east coast from
the mid-Atlantic states to southeastern New England has not changed.
For information on these hazards, see products issued by local
National Weather Service forecast offices at weather.gov.

2. Melissa is expected to gradually weaken and begin moving away
from the U.S. east coast by tonight, resulting in a gradual decrease
in wind and coastal flooding impacts.

FORECAST POSITIONS AND MAX WINDS

INIT 11/1500Z 38.5N 69.6W 55 KT 65 MPH
12H 12/0000Z 38.2N 69.3W 45 KT 50 MPH
24H 12/1200Z 38.4N 67.7W 35 KT 40 MPH
36H 13/0000Z 39.0N 65.1W 30 KT 35 MPH...POST-TROPICAL
48H 13/1200Z 39.9N 61.0W 30 KT 35 MPH...POST-TROPICAL
72H 14/1200Z 41.3N 52.6W 30 KT 35 MPH...POST-TROPICAL
96H 15/1200Z...ABSORBED
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11-10-2019, 20:38   #154
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ST Storm Melissa now. A lot of cold-air cumulus evident as air temperature is only around 16 degrees above SST of 24 degrees.

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19-10-2019, 09:28   #155
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The NHC have strangely classified the ragged low pressure system in the Gulf of Mexico a tropical storm (Nestor). At most it should be subtropical as it has never had any tropical structure and is primarily being fed by an upper trough. It's only just managed to develop a circulation centre.

It's just making landfall along the Florida panhandle this morning.

Water vapour



89 GHZ

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19-10-2019, 09:46   #156
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It's more like a typical MCS, but it has been producing a lot of lightning.

https://uploads.disquscdn.com/images...51b645852d.gif

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25-10-2019, 14:16   #157
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Here we go again?

2. Shower activity has increased this morning near the center of a
large non-tropical low centered a few hundred miles southwest of
the western Azores. Some additional development of this system is
possible during the next couple of days as it moves generally
east-northeastward.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 5 days...low...20 percent.




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25-10-2019, 18:39   #158
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Very very unlikely to develop with any potency from that far North.
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25-10-2019, 21:42   #159
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That system has developed into Tropical Storm Pablo, after the other system in the western Gulf became Tropical Depression Olga a bit earlier. Both are tightly linked with extra-tropical systems and neither will amount to much.

Pablo...

Quote:
Tropical Storm Pablo Discussion Number 1
NWS National Hurricane Center Miami FL AL182019
500 PM AST Fri Oct 25 2019

High-resolution visible satellite imagery gave us a surprise today.
A tropical cyclone has formed within a larger extratropical cyclone
in the northeastern Atlantic. This is not unique and has occurred
several times in the past, primarily during the latter part of the
hurricane season. Pablo is a very small-scale tropical cyclone, but
ASCAT data clearly show a well-defined but small circulation with
40-kt winds embedded within the larger low. This is the intensity
assigned to the cyclone for this advisory. The cloud pattern
consists of an eye-type feature surrounded by a ring of deep
convection. Given the small size of the cyclone, and the baroclinic
environment, the intensity forecast is highly uncertain. At this
time, the NHC forecast calls for a small increase in the winds and
for the cyclone to become extratropical in about 36 hours. However,
this transition could occur sooner than anticipated.

Pablo is currently moving toward the east-southeast at about 9 kt
while embedded within the circulation of the larger extratropical
low. Pablo should then turn toward the northeast with some increase
in forward speed, as indicated by the multi-model consensus aids.
In fact, all the models are in very good agreement, and the NHC
forecast is in the middle of the guidance envelope.

Given that Pablo is embedded within a large extratropical low,
which itself is forecast to bring strong winds to the Azores, the
Portuguese Institute for the Sea and Atmosphere (IPMA) has included
the effects of this small cyclone in their products. Those products
already account for the strong winds and high waves.

FORECAST POSITIONS AND MAX WINDS

INIT 25/2100Z 35.8N 32.2W 40 KT 45 MPH
12H 26/0600Z 35.3N 30.7W 45 KT 50 MPH
24H 26/1800Z 36.3N 26.8W 45 KT 50 MPH
36H 27/0600Z 40.0N 23.5W 45 KT 50 MPH
48H 27/1800Z 43.0N 21.5W 40 KT 45 MPH...POST-TROP/EXTRATROP
72H 28/1800Z 46.5N 20.0W 40 KT 45 MPH...POST-TROP/EXTRATROP
96H 29/1800Z...DISSIPATED
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25-10-2019, 22:49   #160
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Pablo should affect the main Azores eastern islands tomorrow afternoon and then become extratropical and fizzle out between there and here on Monday.




It's a really tiny storm, less than 100 miles across, and is under an area of very strong upper southwesterlies.

Attached Images
File Type: png Pablo.png (71.8 KB, 493 views)
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26-10-2019, 07:31   #161
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In the Indian Ocean, Cyclone Kyarr will get up to CAT 3 over the next couple of days before dissipating harmlessly several hundred km from any land. Those lat/long grids are 2 degrees latitude (120 NM/220 km) tall.

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26-10-2019, 20:47   #162
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Pablo is not really a true tropical storm but more like a medicane, only forming due to high CAPE from a cold upper trough that came down from eastern Canada during the week. SST are only around 23 C, way too low to sustaing a typical tropical system, but the cold upper air is enough to offset this and keep instability high enough to feed convection, aided by high windshear. Pablo is tiny and fairly shallow, with no real signature on microwave imagery. Its formation and is owed to totally non-tropical forces.

Ophelia had some similarities too in that it was also aided by a cold upper trough, boosting instability and also poleward outflow. But it developed more like a true tropical system and grew to be much larger and deeper.

Pablo sounding from today, showing the steep lapse rates and high windshear.



85 GHz Color

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27-10-2019, 06:39   #163
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In the Indian Ocean, Kyarr has intensified further to CAT 4, and could briefly reach CAT 5 later today. The models are completely split on its track. Some say in a couple of days it will take a sharp turn to the northeast, others (and the official JTWC track) say it will turn southwest towards south of Oman. It's an interesting one to watch.

It has a lovely structure after what looks like an eyewall replacement cycle.







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27-10-2019, 15:22   #164
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Quote:
Originally Posted by sdanseo View Post
Very very unlikely to develop with any potency from that far North.
Quote:
Originally Posted by Gaoth Laidir View Post
That system has developed into Tropical Storm Pablo, after the other system in the western Gulf became Tropical Depression Olga a bit earlier. Both are tightly linked with extra-tropical systems and neither will amount to much.
Quote:
Originally Posted by Gaoth Laidir View Post
Pablo should affect the main Azores eastern islands tomorrow afternoon and then become extratropical and fizzle out between there and here on Monday.
Well we were both wrong!
That's two hurricanes now having taken an easterly route towards Ireland in the same year, even if only technically so.



Quote:
056
WTNT43 KNHC 271450
TCDAT3

Hurricane Pablo Discussion Number 8
NWS National Hurricane Center Miami FL AL182019
1100 AM AST Sun Oct 27 2019

Satellite imagery shows that Pablo has continued to maintain a
small eye, and that the eyewall cloud tops have recently cooled.
In addition, early morning microwave satellite intensity estimates,
as well as the CIMSS satellite consensus, indicate that Pablo has
become a hurricane. The initial intensity is increased to 65 kt as
a blend between the subjective estimate from TAFB and the higher
SATCON estimate, and it is possible this is a little conservative.
The intensification has occurred while Pablo is over sea surface
temperatures of 19-20C, and it is likely that cold mid- to
upper-level air temperatures have allowed the cyclone to maintain
deep convection and strengthen over water temperatures where
tropical cyclones normally weaken.

The initial motion is now 030/28. The cyclone is expected to turn
northward and slow its forward motion as it approaches a frontal
system to the north during the next 12-24 h, and this will be
followed by a turn toward the northwest as a large mid-latitude low
over the north central Atlantic becomes the main steering mechanism.
The track guidance has again shifted a little to the east, and the
new forecast track is also nudged a little to the east of the
previous track. Like the previous forecast, it lies close to the
various consensus models.

Pablo should encounter even colder water along the forecast track,
and global model guidance suggests it should merge with the frontal
system between 12-24 h. This combination should cause Pablo to
weaken and become an extratropical cyclone. Thereafter, the system
should be absorbed by the much larger low to its west between 48-72
h.


FORECAST POSITIONS AND MAX WINDS

INIT 27/1500Z 42.8N 18.3W 65 KT 75 MPH
12H 28/0000Z 45.3N 17.2W 55 KT 65 MPH
24H 28/1200Z 46.9N 17.8W 50 KT 60 MPH...POST-TROP/EXTRATROP
36H 29/0000Z 47.9N 18.7W 45 KT 50 MPH...POST-TROP/EXTRATROP
48H 29/1200Z 49.5N 20.3W 40 KT 45 MPH...POST-TROP/EXTRATROP
72H 30/1200Z...DISSIPATED
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27-10-2019, 15:39   #165
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Just to see a Hurricane form in that location really is something else
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