Tropical Cyclone Discussion

756
WTPZ44 KNHC 100842
TCDEP4
 
Tropical Storm Norbert Discussion Number   3
NWS National Hurricane Center Miami FL       EP142026
200 AM PDT Thu Sep 10 2026
 
The tropical cyclone appears to have become better organized
tonight. Earlier visible satellite images showed the low-level
center was fully exposed to the west of the associated deep
convection. Although westerly shear continues to affect the system,
recent proxy-visible satellite images show the center is likely
closer to or just underneath the edge of the cold overcast. Recent
AiDT and D-PRINT estimates from UW-CIMSS are in the 35-39 kt range,
and TAFB provided another 2.5/35-kt Dvorak classification. Based on
these developments, the system is upgraded to Tropical Storm Norbert
with an initial intensity of 35 kt.
 
Norbert is moving westward (280/11 kt) along the southern periphery
of a low- to mid-level ridge over the Eastern Pacific. This feature
will remain entrenched to the north of the system during the next
several days, which should keep Norbert on a westward to
west-northwestward heading through the 5-day forecast period. The
latest NHC track forecast is slightly slower and right of the
previous prediction at days 3-5, generally falling between HCCA and
Google DeepMind at those times. Otherwise, there were no notable
track changes made with this update.
 
The sheared structure of Norbert and the proximity of drier air to
the west of the system suggests that only modest near-term
strengthening should be expected. However, the shear is forecast to
weaken over the next few days while the system moves into a
sufficiently moist environment over 28-29C waters. Despite these
seemingly favorable conditions, there are mixed signals in the
guidance regarding how much strengthening may occur. Overall, the
intensity models trended weaker this cycle, and some minor
adjustments were made to the NHC intensity forecast to account for
this. However, the NHC forecast still lies on the higher end of the
guidance envelope and calls for Norbert to reach hurricane strength
by early next week.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  10/0900Z 16.4N 117.9W   35 KT  40 MPH
 12H  10/1800Z 16.6N 119.9W   40 KT  45 MPH
 24H  11/0600Z 16.7N 122.5W   40 KT  45 MPH
 36H  11/1800Z 16.7N 124.8W   45 KT  50 MPH
 48H  12/0600Z 16.9N 126.9W   50 KT  60 MPH
 60H  12/1800Z 17.3N 128.9W   55 KT  65 MPH
 72H  13/0600Z 17.8N 130.4W   60 KT  70 MPH
 96H  14/0600Z 18.5N 133.5W   65 KT  75 MPH
120H  15/0600Z 18.5N 137.5W   70 KT  80 MPH