Tropical Cyclone Discussion

003
WTPZ43 KNHC 071452
TCDEP3
 
Hurricane Rachel Discussion Number  42
NWS National Hurricane Center Miami FL       EP182026
800 AM PDT Wed Oct 07 2026
 
Recent satellite imagery shows that Rachel's deep convection has
waned over the last couple of hours, however this could be due to
the convective daily minimum. If this is the case, then there is a 
good chance for deep convection to return later. The northern side 
of the cyclone still shows the impact of easterly shear and dry air
intrusions.  The eye of the hurricane is still well defined based
on the proxy-visible satellite imagery. Looking at a combination of
the objective and subjective intensity estimates, the initial
intensity for this advisory is being held at 70 kt.
 
The initial motion for the cyclone is west-northwestward, or 285/6
kt. As of now, Rachel is being steered by high pressure located
over the western United States. However, toward the end of the
week, a large mid- to upper-level trough is expected to approach
from the northwest. This will cause Rachel to slow down and
then turn and accelerate toward Baja California and southern 
California, and the updated NHC forecast track shows Rachel as 
a post-tropical cyclone at 96 h very near the coast. The current NHC 
forecast provides a 120-h track point for forecast continuity, 
however it is likely that the cyclone could dissipate sooner once it 
moves over land. The rest of the forecast is similar to the previous 
track with minor adjustments made based on the latest HCCA and GDMI
forecast aids, except for the track point at 120 h.
 
The hurricane is expected to gradually weaken as it moves into an
unfavorable environment of cooler sea-surface temperatures and
limited moisture. Given how resilient Rachel has been to the
environment, the current intensity trend is on the upper end of the
guidance envelope. There is still a higher-than-normal amount of
uncertainty to the intensity for the latter portion of the forecast.
The trough should induce plenty of wind shear, and the simulated
satellite guidance does show that the cyclone loses convection for a
brief time before it comes back again. The current NHC forecast does
show a post-tropical cyclone at 96 h, however, it is possible that
it could still have tropical-storm-force winds at that point. In
general, the current NHC intensity forecast is very similar to the
previous one with a few changes past 60 h, based on the HCCA and
GDMI forecast aids.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  07/1500Z 20.9N 121.8W   70 KT  80 MPH
 12H  08/0000Z 21.3N 122.6W   65 KT  75 MPH
 24H  08/1200Z 21.9N 123.8W   60 KT  70 MPH
 36H  09/0000Z 22.3N 124.8W   55 KT  65 MPH
 48H  09/1200Z 22.7N 124.9W   50 KT  60 MPH
 60H  10/0000Z 23.5N 123.7W   45 KT  50 MPH
 72H  10/1200Z 25.2N 121.5W   40 KT  45 MPH
 96H  11/1200Z 31.0N 116.8W   40 KT  45 MPH...POST-TROPICAL
120H  12/1200Z 37.9N 114.1W   25 KT  30 MPH...POST-TROP/INLAND