Eastern Pacific Basin Tropical Cyclones

Tropical Storm Georgette Forecast Discussion


715 
WTPZ43 KNHC 291438
TCDEP3

Tropical Storm Georgette Discussion Number   9
NWS National Hurricane Center Miami FL       EP082022
800 AM PDT Fri Jul 29 2022

GOES-17 Proxy-Vis and enhanced IR imagery show that Georgette's 
cloud pattern has become more symmetric with colder -77C inner core 
cloud tops.  An earlier AMSR2 revealed an eye-like feature in the 
lower frequency band and a well-developed rain band in the north 
part of the cyclone.  The eye feature, however, was not evident in 
the infrared presentation.  Although the Dvorak subjective 
T-numbers from TAFB and SAB haven't changed; the initial intensity 
is increased to 50 kt in deference to the microwave image. 

The global models and the statistical intensity guidance indicate 
that the easterly shear will increase within 24 hours, causing 
Georgette to weaken slowly.  However, due to Georgette's compact 
size, intensity fluctuations are possible in the short term.  The 
latest GFS run shows that Georgette could hang on a little longer 
than the NHC forecast indicates, possibly as a post-tropical 
cyclone.  Therefore, adjusting the forecast may be deemed necessary 
to extend the cyclone's life in subsequent advisories.  The official 
forecast is very close to the HCCA and IVCN intensity aids.

Georgette's initial motion is estimated to be just a bit south of 
due west or 260/11 kt.  A mid-tropospheric ridge stretching 
east-northeast to west-southwest should steer the small cyclone 
west to west-southwestward during the next 48 hours.  Afterward, a 
reduction in forward speed along with a turn toward the northeast 
is expected in response to larger Frank weakening the ridge and 
disrupting the steering flow while passing to the northeast of 
Georgette.  Although the ECMWF global has been the best performer 
in the eastern Pacific this season with respect to forecast track, 
the model continues to initialize poorly the compact TC indicating 
a significantly weaker system while remaining the left tracker 
outlier.  The GFS, however, now has a more accurate depiction of 
the cyclone's size and vertical depth and shows a more direct 
response to Frank's larger wind field.  There still is quite a bit 
of uncertainty in Georgette's future track as evident by the larger 
than usual guidance spread, particularly after the northeast turn.  
Consequently, this is a low confidence forecast.  The NHC forecast 
is similar to the previous advisory through 48 hours, but has been 
adjusted to the left beyond that point to agree more with the HCCA 
and GEFS/EPS ensemble member solutions.


FORECAST POSITIONS AND MAX WINDS

INIT  29/1500Z 15.1N 123.0W   50 KT  60 MPH
 12H  30/0000Z 14.7N 124.3W   50 KT  60 MPH
 24H  30/1200Z 14.2N 125.7W   50 KT  60 MPH
 36H  31/0000Z 13.9N 126.7W   45 KT  50 MPH
 48H  31/1200Z 13.7N 127.2W   45 KT  50 MPH
 60H  01/0000Z 14.0N 127.3W   40 KT  45 MPH
 72H  01/1200Z 14.6N 126.7W   40 KT  45 MPH
 96H  02/1200Z 17.0N 124.9W   35 KT  40 MPH
120H  03/1200Z...DISSIPATED

$$
Forecaster Roberts




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