Tropical Depression Two-C (future Tropical Storm Moke)

The convection around Tropical Depression Two-C has continued to show some improvements since the last advisory, and the low-level circulation is a little better defined, as evident in satellite data. Both NOAA and Air Force aircraft reconnaissance will investigate the cyclone tomorrow.

The system appears to be moving west-northwestward at about 13 kt, and that motion is expected to persist for the next 48 hours or so until the ridge north of it strengthens. This steering flow is expected to force the system to turn more toward the west in a few days. It is important to note that interests in the Hawaiian Islands, especially the Big Island, should monitor the progress of this system.

The cyclone is expected to be in a mostly favorable environment for the next couple of days, which should allow for gradual strengthening to a high-end tropical storm or a category one hurricane as the system moves toward the Hawaiian Islands. Beyond that time, wind shear will likely start to increase and dry air will also begin to to intrude into the cyclone. The current NHC intensity forecast calls for a peak wind speed of 55 kt this weekend, with gradual weakening occuring after that.

Key Messages

1. The tropical depression is expected to strengthen while it moves west-northwestward toward the Hawaiian Islands late this week and this weekend.

2. Heavy rainfall associated with Tropical Depression Two-C is expected to begin to impact the Big Island of Hawaii late Saturday night, spreading westward across the remainder of the Hawaiian Islands Sunday into Monday. This rainfall may produce life-threatening flooding and mudslides, especially in steep terrain and over areas that were affected recently by Lala.

3. There is a risk of wind and wave impacts in the Hawaiian Islands regardless of the exact track and intensity of the system. Watches may be required for portions of the Hawaiian Islands tonight or Friday and residents there should closely monitor the latest forecast updates and ensure that they have their preparedness plan in place.

last updated 1100 AM HST Thu Aug 20 2026