


Tropical Cyclone Discussion
Issued by NWS
Issued by NWS
115 WTPZ45 KNHC 072039 TCDEP5 Tropical Storm Octave Discussion Number 31 NWS National Hurricane Center Miami FL EP152025 200 PM PDT Tue Oct 07 2025 Octave continues to produce clusters of deep convection, though this activity is becoming more fragmented and displaced southwest of the now exposed low-level center. This structure is largely the result of increasing east-northeasterly shear related to much larger Hurricane Priscilla to the northeast. While the subjective Dvorak estimates remain T3.0/45-kt, the objective intensity estimates are now all under 40 kt, and a recent scatterometer pass only had a peak derived wind of 37 kt. Thus, the initial intensity for Octave is lowered to 40 kt this advisory. Now that the center is mostly exposed, its been a little easier to track the center, with its motion estimated east-southeastward at 110/7 kt. Octave`s primary steering currents are low to mid-level westerlies that are partially related to the circulation of Priscilla and the larger monsoonal flow that has developed across the eastern Pacific. As the storm reaches Priscilla`s longitude, Octave`s track will likely bend more poleward as it rounds the outer edge of Priscilla`s flow. The latest NHC track forecast is close to the prior one, but is a little faster after 24 h, following the latest trends in the HCCA and Google DeepMind guidance. The current 20-25 kt of vertical wind shear is expected to increase further to 30-35 kt over the next 24-36 h. Thus, Octave is expected to continue weakening, but will likely to continue to produce sheared bursts of deep convection as it continues to traverse warm sea-surface temperatures. After 48 hours, most of the guidance shows the cyclone degenerating into a trough, roughly between Priscilla to its northwest and another developing system (EP90) to its southeast. The NHC intensity forecast is a bit lower than earlier, and now shows dissipation in 60 h, though this could occur sooner than shown here given the hostile environmental conditions. This forecast is roughly in the middle of the model consensus. FORECAST POSITIONS AND MAX WINDS INIT 07/2100Z 15.3N 118.8W 40 KT 45 MPH 12H 08/0600Z 15.2N 117.7W 40 KT 45 MPH 24H 08/1800Z 15.7N 115.6W 35 KT 40 MPH 36H 09/0600Z 16.6N 113.1W 30 KT 35 MPH 48H 09/1800Z 17.4N 110.5W 25 KT 30 MPH 60H 10/0600Z...DISSIPATED $$ Forecaster Papin