####018002431####
WTPZ43 KNHC 230241

TCDEP3

 

Tropical Storm Otis Discussion Number   3

NWS National Hurricane Center Miami FL       EP182023

1000 PM CDT Sun Oct 22 2023



Convection has been pulsing in the northwestern quadrant of Otis 

during the past several hours, with less overall convective 

activity than this afternoon.  Microwave data and ship reports 

suggests the center is southeast of the main area of deep 

convection.  The initial wind speed is kept at 35 kt, in line with 

recent Dvorak T-number estimates.  

 

Otis appears to be moving north-northwest at about 4 kt.  The 

biggest change to report on this advisory is that there's been a 

notable northwest shift in the NHC track forecast.  The synoptic 

pattern of a trough over northwestern Mexico and a ridge over the 

northwestern Caribbean would seem to favor a slow north-northwest 

track for the next few days.  Much of the GFS-based guidance, 

however, appears to be too intertwined with the Intertropical 

Convergence Zone, resulting in many of the aids not showing enough 

motion during the next few days or even a track southward.  

This doesn't seem realistic, and I've adjusted the forecast a large 

distance to the northwest, with further northwest track changes 

possible on later forecasts.  



The storm will likely be in an environment of light-to-moderate 

shear, with fairly high mid-level humidity over very warm water.  

These conditions should promote gradual strengthening, which is 

shown to begin after 12 hours to give the system some time to 

re-align vertically.  An increase in shear and possible land 

interaction is forecast to cause Otis to level off in intensity 

around midweek. This NHC intensity prediction is near the higher 

end of the guidance, closer to the statistical guidance than the 

dynamical models, the latter of which seem to be too low given the 

large-scale environment.

 

 

FORECAST POSITIONS AND MAX WINDS

 

INIT  23/0300Z 11.1N  97.3W   35 KT  40 MPH

 12H  23/1200Z 11.7N  97.4W   35 KT  40 MPH

 24H  24/0000Z 12.6N  97.6W   40 KT  45 MPH

 36H  24/1200Z 13.6N  97.9W   45 KT  50 MPH

 48H  25/0000Z 14.5N  98.3W   50 KT  60 MPH

 60H  25/1200Z 15.2N  98.7W   50 KT  60 MPH

 72H  26/0000Z 16.1N  99.3W   50 KT  60 MPH

 96H  27/0000Z 17.6N 100.6W   35 KT  40 MPH...INLAND

120H  28/0000Z...DISSIPATED

 

$$

Forecaster Blake