Tropical Cyclone Discussion
894 WTPA43 PHFO 220848 TCDCP3 Tropical Storm Moke Discussion Number 8 NWS Central Pacific Hurricane Center Honolulu HI CP022026 Issued by NWS National Hurricane Center Miami FL 1100 PM HST Fri Aug 21 2026 Moderate southwesterly vertical wind shear continues to displace the deepest convection north of the low-level circulation center, where convection has expanded in coverage and cloud-top temperatures have cooled to around -85 C over the past several hours. Despite the recent increase in convection, data from an Air Force Reserve Hurricane Hunter aircraft indicate little change in intensity, with a central pressure of 999 mb and peak 850-mb flight-level winds of 50 kt in the northeastern quadrant. Based on these data, the initial intensity is held at 40 kt for this advisory. Moke is moving west-northwestward, or 300/7 kt. There has been little change to the track forecast philosophy. A low- to mid-level ridge is forecast to strengthen north of Moke during the next few days, which should steer the cyclone west-northwestward at a slightly faster forward speed. This motion is expected to take the core of Moke south of the main Hawaiian Islands this weekend into early next week. The latest track guidance remains fairly tightly clustered, and the NHC forecast is similar to the previous advisory. Given the expected track south of the islands and the compact nature of the cyclone, the likelihood of tropical storm watches or warnings for the main Hawaiian Islands remains very low. However, the enhanced pressure gradient north of Moke, combined with moisture associated with the cyclone interacting with the island terrain, will likely produce gusty winds and periods of heavy rainfall across portions of the state. These impacts could be aggravated by antecedent conditions from Lala last weekend, particularly in areas where soils remain saturated. Some additional strengthening is possible during the next day or so despite the moderate southwesterly vertical wind shear currently affecting Moke. Thereafter, dry mid-level air is expected to become increasingly entrained into the circulation while vertical wind shear remains unfavorable late this weekend into early next week. These factors should cause Moke to gradually weaken as it passes south of the Hawaiian Islands. The latest NHC intensity forecast is similar to the previous advisory and remains near the upper end of the guidance envelope. Key Messages: 1. Heavy rainfall associated with Moke will begin to impact the Big Island of Hawaii late Saturday, with rain spreading westward across the remainder of the Hawaiian Islands Sunday into Monday. This rainfall may produce life-threatening flooding and mudslides for the windward and southeast Big Island, especially in steep terrain and over areas that were affected recently by Lala. 2. Although the strongest winds associated with Moke are expected to pass south of the Hawaiian Islands, strong gusty winds are likely, particularly in areas within and downslope of higher terrain. 3. Swells generated by the storm may cause life-threatening surf and rip current conditions this weekend and early next week for exposed east and south facing shores of the Hawaiian Islands. FORECAST POSITIONS AND MAX WINDS INIT 22/0900Z 14.4N 149.0W 40 KT 45 MPH 12H 22/1800Z 15.0N 150.7W 45 KT 50 MPH 24H 23/0600Z 15.4N 152.8W 50 KT 60 MPH 36H 23/1800Z 15.8N 155.2W 45 KT 50 MPH 48H 24/0600Z 16.4N 157.8W 40 KT 45 MPH 60H 24/1800Z 16.8N 160.2W 40 KT 45 MPH 72H 25/0600Z 17.2N 162.6W 35 KT 40 MPH 96H 26/0600Z 18.2N 167.8W 35 KT 40 MPH 120H 27/0600Z 19.2N 172.3W 30 KT 35 MPH