Tropical Depression 27W (#Paolo) – Tropical Cyclone Advisory #2: 1200 UTC 1 October 2025

…Tropical Depression 27W getting better organized as it continues moving toward Luzon…

Current storm information:

• Position: 14.7°N 130.0°E

• Movement: W at 8 knots (15 km/h)

• Intensity: 30 knots (55 km/h) 

• Central pressure: 1004 hPa

Trend:

• Some strengthening is forecast during the next 24 hours, and the depression will likely become a tropical storm later tonight or early Thursday.

Discussion:

The tropical depression that formed well to the east of Luzon earlier today - now Tropical Depression 27W - is showing signs of getting better organized, although if you looked at a conventional satellite image of it, you might not know it. Convection associated with the depression is somewhat fragmented and is flaring in clusters rotating around the center. Despite this, microwave satellite imagery indicates that the convection is beginning to organize into bands wrapping into the center from the west. Most of the convection is a bit lopsided to the west of the center, likely due to some mid-level easterly shear affecting the system. The intensity is held at 30 kts, based on Dvorak estimates ranging from T2.0 to T2.5 and CIMSS ADT and D-PRINT estimates of 30 to 31 kts. 

The forecast is kind of problematic. TD 27W has about 36 hours over water before it moves inland over northern Luzon on Friday. The global models and the dynamical HAFS-A model don’t show much strengthening before then, which is odd as the system is in an extremely favorable environment with low shear and very warm SSTs. The ensemble models (GEFS/ECMWF/Google DeepMind) and the rapid intensification guidance AI-RI and RIPA have picked up on this and indicate very high probabilities of rapid intensification, with RIPA indicating an 86% chance of an increase of 70 knots in the next 48 hours, which is the most extreme parameter the model shows. It seems reasonable to believe that 27W will intensify significantly before landfall in northern Luzon, and it is possible it could strengthen more than indicated below. The short-term track forecast has been nudged slightly north of the previous one based on model trends, and a 36-hour forecast point has been provided as the first landfall will likely occur between the 36-hour and 48-hour forecast points.

After landfall, 27W should weaken somewhat as it crosses rugged terrain, but once it emerges over the South China Sea on Friday night, it should once again find itself in an extremely favorable environment. Substantial strengthening is forecast as it quickly moves west-northwestward across the South China Sea, and 27W could be near Category 2 strength by the time it moves over the Leizhou Peninsula on Sunday. Rapid weakening is forecast after this landfall as it moves over southern China and far northeastern Vietnam through the end of the forecast period.

Forecast positions and maximum winds

• 000 hrs: 14.7°N 130.0°E – 30 kts 

• 012 hrs: 15.4°N 128.1°E – 40 kts 

• 024 hrs: 16.1°N 125.8°E – 55 kts

• 036 hrs: 16.9°N 123.4°E – 65 kts off the Luzon coast

• 048 hrs: 17.8°N 120.2°E – 50 kts over water

• 072 hrs: 19.0°N 114.8°E – 85 kts 

• 096 hrs: 21.0°N 110.1°E – 80 kts inland

• 120 hrs: 22.3°N 106.0°E – 45 kts inland