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Tropical Storm Georgette Discussion Number 16
NWS National Hurricane Center Miami FL EP082022
200 AM PDT Sun Jul 31 2022
After briefly becoming exposed earlier tonight, there was another
deep convective burst near the center of Georgette that started
around 04 UTC. Significant lightning activity was observed on the
GOES-17 GLM around that time, though it lacked organization without
much cyclonic rotation of the flashes in the up-shear direction.
More recently, the convective cloud tops have been warming and are
being sheared off westward by upper-level easterly flow. The latest
satellite intensity estimates continue to provide a wide spread of
values from 30 to 50 kt. However, we also received a partial ASCAT-B
pass over Georgette at 0612 UTC, revealing peak wind-retrievals of
only 20-25 kt on the east side of Georgette. Assuming stronger winds
are occuring on the west side of the cyclone, the latest intensity
was reduced to only 40 kt for this advisory.
Georgette has stubbornly maintained a south of due west heading,
though it might be starting to slow down at 260/6 kt. As previously
discussed, Georgette's track forecast remains challenging, mainly
due to the difficulty in determining when Georgette will finally
halt its westward motion. The steering flow is expected to collapse
as the larger Hurricane Frank passes by well to the north of
Georgette. After this occurs, the steering currents are then
expected to veer out of the south, finally allowing Georgette to
begin a north or north-northeastward motion in 36-60 hours. At the
end of the forecast, a low-level ridge is expected to build back
in north of Georgette, resulting in a westward turn by 120 hours.
Similar to the previous forecast cycle, the GFS remains on the far
right/east side of the track guidance, while the ECMWF and its
ensemble mean remains on the far left/west side. The latest forecast
track leans towards the ECMWF and its ensemble mean as this guidance
has preformed better for Georgette so far. This results in another
westward shift in the NHC forecast track, which is also west of the
multi-model consensus aids that have been heavily influenced by the
poorly preforming GFS track so far.
The intensity forecast for Georgette is more straightforward. At
least moderate easterly vertical wind shear is expected to continue
over Georgette for the next 24-36 hours, and some additional
weakening is expected in the short term. However, there may be a
brief respite in this shear as mid-level relative humidity moistens
some between 48-60 hours, and the latest forecast now shows a bit of
re-intensification in that time period. By the end of the forecast,
Georgette is likely to move towards cooler waters and its remaining
convection will likely fade. However, it is interesting to note the
latest GFS, ECMWF, CMC, and UKMET keep Georgette as a closed
circulation through 120 hours, and so the latest forecast now shows
Georgette as a remnant low at that time. This intensity forecast is
in good agreement with the intensity consensus aids HCCA and IVCN.
FORECAST POSITIONS AND MAX WINDS
INIT 31/0900Z 13.3N 129.3W 40 KT 45 MPH
12H 31/1800Z 13.2N 130.0W 35 KT 40 MPH
24H 01/0600Z 13.1N 130.5W 35 KT 40 MPH
36H 01/1800Z 13.5N 130.6W 35 KT 40 MPH
48H 02/0600Z 14.0N 130.5W 40 KT 45 MPH
60H 02/1800Z 15.0N 130.3W 40 KT 45 MPH
72H 03/0600Z 16.0N 130.0W 35 KT 40 MPH
96H 04/0600Z 17.0N 131.0W 30 KT 35 MPH
120H 05/0600Z 16.5N 134.0W 25 KT 30 MPH...POST-TROP/REMNT LOW
$$
Forecaster Papin
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