Eastern Pacific Basin Tropical Cyclones

Tropical Storm Georgette Forecast Discussion


000
WTPZ43 KNHC 310851
TCDEP3

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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