Eastern Pacific Basin Tropical Cyclones

Tropical Storm Orlene Forecast Discussion


000
WTPZ41 KNHC 291444
TCDEP1

Tropical Storm Orlene Discussion Number   3
NWS National Hurricane Center Miami FL       EP162022
1000 AM CDT Thu Sep 29 2022

Satellite imagery this morning shows that Orlene is getting better
organized, with the formation of a small central dense overcast
with an outer convective band in the northwestern semicircle.
Satellite intensity estimates are 35-40 kt, so the initial
intensity is increased to 40 kt.

The initial motion is west-northwestward or 295/9 kt.  Orlene is 
being steered by a mid-level ridge over Mexico, and this general 
motion should continue for the next day or so.  After that time, the 
cyclone reaches the western end of the ridge.  The UKMET and ECMWF, 
which forecast less development, take the storm more westward south 
of Baja California, while the GFS and the Canadian, which forecast a 
stronger and more vertically deep storm, forecast Orlene to turn 
northward into the southern Gulf of California toward northwestern 
Mexico.  Give the current trends and the forecast intensities, the 
track forecast leans towards the GFS/Canadian solution and shows 
Orlene turning northward and moving into northwestern Mexico between 
days 4-5.  The new forecast track is similar to the previous 
forecast.

Orlene is forecast to be within an environment of low vertical wind
shear and plenty of atmospheric moisture while over warm waters for
the 72 h or so. The majority of guidance, except the aforementioned 
ECMWF and UKMET, indicate steady strengthening during this time, 
and bring Orlene to hurricane intensity by 36 h.  The intensities 
during the first 72 h have been increased to better match the trend 
of the intensity guidance.  After 72 h, Orlene is likely to 
encounter increasing shear and a drier air mass, which should  
cause weakening.  However, the GFS, HWRF, and HMON models suggest 
the possibility that the cyclone will still be at hurricane 
strength when it reaches the coast of Mexico, and the new intensity 
forecast follows that scenario.


FORECAST POSITIONS AND MAX WINDS

INIT  29/1500Z 15.1N 105.9W   40 KT  45 MPH
 12H  30/0000Z 15.8N 107.0W   45 KT  50 MPH
 24H  30/1200Z 16.6N 108.0W   55 KT  65 MPH
 36H  01/0000Z 17.4N 108.4W   65 KT  75 MPH
 48H  01/1200Z 18.2N 108.5W   75 KT  85 MPH
 60H  02/0000Z 19.3N 108.4W   80 KT  90 MPH
 72H  02/1200Z 20.5N 108.1W   85 KT 100 MPH
 96H  03/1200Z 22.9N 107.6W   65 KT  75 MPH
120H  04/1200Z 26.0N 107.0W   25 KT  30 MPH...INLAND

$$
Forecaster Beven



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