Eastern Pacific Basin Tropical Cyclones

Tropical Storm Georgette Forecast Discussion


000
WTPZ43 KNHC 282053
TCDEP3

Tropical Storm Georgette Discussion Number   6
NWS National Hurricane Center Miami FL       EP082022
200 PM PDT Thu Jul 28 2022

After the previous advisory, there was a high-resolution GMI 
microwave pass over Georgette at 1522 UTC that indicated that deep 
convection mentioned in the previous discussion may have helped to 
align the low and mid-level centers. More recently, Georgette has 
maintained a small area deep convection between -70 to -75 C near 
its center, though there is evidence of easterly shear impinging on 
the outflow layer. Dvorak satellite estimates were T3.0/45-kt from 
both TAFB and SAB, and T2.9/43-kt from UW-CIMSS ADT. The initial 
intensity is being held at 45-kt this advisory.

Georgette has been moving right of the previous forecast track, 
maintaining a south of due west heading at 260/10 kt, a bit faster 
than before. Part of this faster and more rightward motion could be 
due in part to the cyclone being more vertically aligned than 
depicted in the dynamical models. In fact, the latest 12 UTC GFS and 
ECMWF are still struggling to resolve Georgette's current structure, 
with both models depicting the mid-level vortex tilted about 100 n 
mi NNE of the low-level center, which does not match the center 
embedded in the deep convection as seen on visible satellite imagery 
currently. Regardless, the track guidance has made a notable shift 
right this forecast cycle, and more guidance keeps Georgette 
separate from the larger circulation of Frank to its east over the 
next 3-4 days. Thus, the latest track forecast now shows a faster 
and farther westward track over the next 48 hours, favoring the 
right side of the track guidance envelope due to the more vertically 
coupled structure. After 60 hours, the tropical cyclone is expected 
to make a sharp turn to the north and then northeast as it becomes 
embedded in large-scale monsoonal southwesterly flow to the south of 
the larger low-level circulation of Frank.  he latest NHC forecast 
leans heavily on a blend between the latest ECMWF forecast (EMXI) 
and its ensemble mean (EMNI), which have been on the right side of 
the guidance envelop. However, given the still large west-to-east 
spread in the ensemble tracks in 72 hours, the track forecast still 
has higher-than-normal uncertainty. 

Georgette still has an opportunity to intensify a bit more in the 
short-term, as the easterly shear is not expected to increase much 
in the next 24 hours as the cyclone remains over 28C sea surface 
temperatures. However, something to watch out for is the possibility 
of dry-air entrainment given the very dry mid-level relative 
humidity environment. Stable stratocumulus clouds are also seen 
immediately to the northeast of Georgette's cirrus shield, and if 
that is ingested into the core, it could disrupt the storm's 
structure. After 36 hours, the easterly shear could increase further 
as Frank's upper-level outflow begins to impinge on the much smaller 
Georgette. At the end of the forecast, Georgette is forecast to be 
caught in strong southwesterly monsoonal flow to the south of Frank 
and it could open up into a trough axis by 120 hours. The NHC 
intensity forecast is quite similar to the previous one, and still 
lies near the LGEM guidance.


FORECAST POSITIONS AND MAX WINDS

INIT  28/2100Z 15.6N 120.1W   45 KT  50 MPH
 12H  29/0600Z 15.1N 121.3W   50 KT  60 MPH
 24H  29/1800Z 14.6N 122.8W   50 KT  60 MPH
 36H  30/0600Z 14.1N 123.7W   50 KT  60 MPH
 48H  30/1800Z 13.7N 124.3W   45 KT  50 MPH
 60H  31/0600Z 13.8N 124.5W   45 KT  50 MPH
 72H  31/1800Z 14.7N 124.0W   40 KT  45 MPH
 96H  01/1800Z 17.5N 123.0W   35 KT  40 MPH
120H  02/1800Z...DISSIPATED

$$
Forecaster Papin



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