Eastern Pacific Basin Tropical Cyclones

Tropical Storm Newton Forecast Discussion

WTPZ45 KNHC 230850

Tropical Storm Newton Discussion Number   7
NWS National Hurricane Center Miami FL       EP152022
300 AM MDT Fri Sep 23 2022

Tonight's satellite presentation consists of a pulsating, shapeless
convective mass just east of the surface circulation.  A 0430 UTC 
METOP-B ASCAT pass revealed peak surface winds of 33 kt in the east 
quadrant.  A blend of the Dvorak satellite intensity estimates from 
TAFB and SAB along with the likely under-sampled scatterometer pass 
supports lowering the initial intensity to 45 kt.

Slow weakening is forecast while the cyclone moves into a dry, 
stable lower boundary marine layer invading from the northwest.  The 
statistical SHIPS and the global models also indicate that Newton 
will encounter increasing southerly shear.  Again, these factors are 
likely to result in slow weakening and degeneration to a remnant low 
no later than Saturday night.

Newton's initial motion is estimated to be west-northwestward, or 
285/6 kt.  The cyclone is moving along the southwest periphery of a
subtropical ridge stretching westward from northwestern Mexico.
Newton should continue in this general direction through early 
Sunday, then turn west-southwestward within the trade wind flow 
through the end of the period as a vertically shallow remnant low.  
Only a slight adjustment was made to the south of the previous 
forecast beyond the 48-hour period to come in closer agreement with 
the NOAA HFIP HCCA model.


INIT  23/0900Z 18.1N 110.4W   45 KT  50 MPH
 12H  23/1800Z 18.4N 111.5W   45 KT  50 MPH
 24H  24/0600Z 19.1N 113.1W   45 KT  50 MPH
 36H  24/1800Z 19.7N 114.8W   40 KT  45 MPH
 48H  25/0600Z 19.8N 116.3W   35 KT  40 MPH
 60H  25/1800Z 19.2N 117.7W   30 KT  35 MPH...POST-TROP/REMNT LOW
 72H  26/0600Z 18.1N 118.9W   25 KT  30 MPH...POST-TROP/REMNT LOW
 96H  27/0600Z...DISSIPATED

Forecaster Roberts

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