Eastern Pacific Basin Tropical Cyclones

Tropical Storm Newton Forecast Discussion


022 
WTPZ45 KNHC 222042
TCDEP5

Tropical Storm Newton Discussion Number   5
NWS National Hurricane Center Miami FL       EP152022
300 PM MDT Thu Sep 22 2022

Convection in the core of Newton has collapsed rather suddenly in 
the past few hours, likely due to the ingestion of dry air.  The 
central dense overcast is largely gone and only small bursts of 
convection are still firing near the estimated center where cloud 
top temperatures are warmer than -70 degrees C.  Subjective Dvorak 
classification still range between 35 to 55 kt, though the objective 
estimates have been declining since the previous advisory.  The 
initial intensity has therefore been lowered to 50 kt.

Newton continues to move west-northwestward at 285/6 kt.  The 
cyclone is moving along the southwest periphery of a 
well-established ridge centered over Texas.  This ridge will be the 
main feature steering the storm until the shallow vortex turns 
westward in about 3 days.  The model guidance envelope has shifted 
northward beyond the 36 hour forecast period.  In response, the 
official track forecast has been shift slightly to the right of 
previous advisory after a day or so.

The small size of Newton has made it susceptible to modest changes 
in the near-storm environment.  Though the statistical guidance is 
analyzing low vertical wind shear, the satellite presentation of the 
storm would suggest a dry air intrusion has interrupted 
strengthening and induced weakening.  Forecast Intensity Guidance  
now indicates Newton will weaken and ultimately become a remnant low 
in a couple of days or so.  The NHC intensity prediction no longer 
shows strengthening and instead calls for gradual weakening until 
dissipation at 96 hours. 

FORECAST POSITIONS AND MAX WINDS

INIT  22/2100Z 18.0N 109.0W   50 KT  60 MPH
 12H  23/0600Z 18.2N 110.0W   45 KT  50 MPH
 24H  23/1800Z 18.7N 111.6W   45 KT  50 MPH
 36H  24/0600Z 19.3N 113.2W   40 KT  45 MPH
 48H  24/1800Z 19.8N 114.7W   35 KT  40 MPH
 60H  25/0600Z 20.0N 116.2W   30 KT  35 MPH...POST-TROP/REMNT LOW
 72H  25/1800Z 19.9N 117.6W   25 KT  30 MPH...POST-TROP/REMNT LOW
 96H  26/1800Z...DISSIPATED

$$
Forecaster Bucci




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