Advisories

000
WTPZ43 KNHC 271444
TCDEP3
 
Tropical Depression Eighteen-E Discussion Number   2
NWS National Hurricane Center Miami FL       EP182026
900 AM CST Sun Sep 27 2026
 
Deep convection is gradually becoming better organized in
association with the depression.  There is evidence of banding over
the northern and western portions of the circulation, although
there appears to be some easterly shear over the system.  TAFB
provided a Dvorak classification of T2.5/35 kt and objective
estimates are in the 30-35 kt range.  Given the fragmented nature
of the convective banding, the initial intensity is held at 30 kt.  
A very recent arriving WSF-M microwave overpass was very helpful 
in locating the center, which was a little north of the previous 
estimate.

The initial motion appears to be 295/4 kt, a little slower than 
estimated in the first advisory.  The depression is forecast to 
move faster toward the west-northwest, to the south of a 
deep-layer ridge over Mexico during the next several days.  The 
track guidance is in good agreement on the core of the system 
staying well south of the coast of southern Mexico, and the NHC 
track forecast follows a blend of the GDM consensus aid and the HFIP 
corrected consensus.  The new track was adjusted slightly north of 
the previous advisory due to the more northward initial position.
 
Moderate easterly shear over the system is likely to keep 
significant strengthening in check during the next 12 hours, but the 
system is likely to become a tropical storm during that time. By 
late tonight and Monday, a faster rate of strengthening is expected 
as shear decreases and the system moves over warm SSTs.  Much of 
the intensity guidance shows the system becoming a hurricane in 
about 48 hours, and the NHC wind speed forecast follows suit.  
Around 72 hours, there is some uncertainty with regards to SSTs 
with the track potentially moving over the cool wake of Hurricane 
Polo. Therefore, the intensity forecast during that period calls 
for the intensity to level off, which is similar to what is shown 
by the HFIP corrected consensus. 


FORECAST POSITIONS AND MAX WINDS
 
INIT  27/1500Z 12.7N  98.6W   30 KT  35 MPH
 12H  28/0000Z 13.0N  99.2W   35 KT  40 MPH
 24H  28/1200Z 13.7N 100.5W   45 KT  50 MPH
 36H  29/0000Z 14.6N 102.4W   55 KT  65 MPH
 48H  29/1200Z 15.5N 104.2W   65 KT  75 MPH
 60H  30/0000Z 16.5N 106.0W   70 KT  80 MPH
 72H  30/1200Z 17.3N 107.4W   75 KT  85 MPH
 96H  01/1200Z 18.7N 109.2W   80 KT  90 MPH
120H  02/1200Z 19.4N 110.0W   80 KT  90 MPH
 
$$
Forecaster Brown