Eastern Pacific Basin Tropical Cyclones

Tropical Storm Paine Forecast Discussion


000
WTPZ42 KNHC 040239
TCDEP2

Tropical Storm Paine Discussion Number   2
NWS National Hurricane Center Miami FL       EP172022
900 PM MDT Mon Oct 03 2022

The structure of Paine this evening appears to be holding steady, 
with deep convective cloud tops between -70 to -80 C pulsing 
primarily to the east of the well-defined low-level center. While 
deep-layer vertical wind shear diagnosed by SHIPS guidance is 
currently low (under 10 kt), the shear below this layer appears to 
be higher, and this is likely what is resulting in the current 
sheared appearance on satellite. Subjective Dvorak numbers from both 
TAFB and SAB were CI 2.0/30-kt at 0000 UTC, while UW-CIMSS ADT was a 
bit higher at T2.5/35-kt. The initial intensity is held at 35-kt in 
deference to the earlier ASCAT data and higher ADT estimate.

The regional hurricane guidance suggests the environmental mid-level 
shear will continue, and the deep-layer shear is expected to 
increase markedly after 24 hours. In addition, the tropical cyclone 
is embedded in a dry mid-level environment (sub 50 percent) which 
should also prevent significant convective organization in the 
short-term. Still, the 12 hour forecast provides an opportunity for 
the storm to intensify a bit during the diurnal convective maximum. 
However, Paine's intensification is likely to be short-lived, with 
gradual weakening expected thereafter as shear increases and the 
thermodynamic environment begins to decline. The simulated IR 
imagery from the ECWMF and HWRF models suggest convection will 
subside near the cyclone in the 48-60 hour mark, and the latest 
forecast makes Paine a remnant low by the 60 h mark. The intensity 
forecast largely follows the latest consensus aids, aside from being 
a bit higher in 12 h, similar to the LGEM guidance.

The initial motion remains off to the north-northwest estimated at 
335/5 kt. The cyclone is currently feeling a mid-level weakness in 
the ridge to its north which should allow the system to gain more 
latitude in the short-term while it remains convectively coupled. 
However by 36-48 hours, this convective activity should wane, 
leaving Paine to be steered more by the low-level trade winds, 
generally westward. The track guidance this cycle is in two camps, 
with the ECMWF and regional hurricane models (HWRF/HMON) faster to 
the north, while the GFS and Canadian, which do not have a good 
current representation of Paine, are slower and turn the cyclone to 
the west earlier. The track forecast follows closer to the ECMWF and 
the HFIP corrected consensus approach, which leans towards a 
somewhat faster and more poleward motion for the first 48 hours of 
the forecast.


FORECAST POSITIONS AND MAX WINDS

INIT  04/0300Z 16.5N 112.3W   35 KT  40 MPH
 12H  04/1200Z 17.2N 112.6W   40 KT  45 MPH
 24H  05/0000Z 18.0N 113.1W   35 KT  40 MPH
 36H  05/1200Z 18.7N 113.8W   35 KT  40 MPH
 48H  06/0000Z 19.1N 114.2W   30 KT  35 MPH
 60H  06/1200Z 19.3N 114.7W   25 KT  30 MPH...POST-TROP/REMNT LOW
 72H  07/0000Z 19.3N 115.4W   25 KT  30 MPH...POST-TROP/REMNT LOW
 96H  08/0000Z...DISSIPATED

$$
Forecaster Papin



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