000 WTPA41 PHFO 241442 TCDCP1 Tropical Storm Hone Discussion Number 9 NWS Central Pacific Hurricane Center Honolulu HI CP012024 500 AM HST Sat Aug 24 2024 Satellite imagery indicates that the appearance of Tropical Storm Hone remains steady, with minimal changes in track or intensity over the past 6 h. Deep convection and convective banding continue to present a well-organized structure. Recent data from a U.S. Air Force Reserve Hurricane Hunter aircraft showed maximum sustained flight-level winds of 64 knots, which, after adjustment, reduces to 51 knots at the surface. SFMR winds were recorded at 59 knots. Considering these observations, the initial intensity will be maintained at 55 knots. The central pressure remains at 998 mb as confirmed by dropsonde data. The initial motion is set at 280/13. This general motion, slightly north of due west, is expected to continue over the next several days under the influence of a subtropical ridge to the north. Some slowing of forward motion is anticipated as the ridge weakens slightly. Hone is expected to pass near or just south of the Big Island of Hawaii later today through early Sunday, where a Tropical Storm Warning remains in effect. By the middle of next week, Hone will likely become increasingly shallow as vertical wind shear increases, allowing the low-level trade wind flow to steer the system toward the west-southwest. The official forecast track is nearly identical to the previous advisory, and closely follows the tightly clustered consensus guidance. Environmental conditions are expected to remain steady over the next 24 h, with sea surface temperatures between 26C and 27C, light to moderate vertical wind shear, and marginally sufficient mid-level moisture. Slow strengthening is expected to continue. Sea surface temperatures are forecast to rise to around 27C beyond 24 h, and oceanic heat content will become more favorable. This supports the potential for Hone to reach hurricane strength from Sunday through Monday. As Hone continues westward, increasing vertical wind shear is likely to weaken the system later Monday through the middle of next week. The intensity forecast is aligned with dynamical consensus guidance. KEY MESSAGES: 1. There is the potential for excessive rainfall and flash flooding on portions of the Big Island of Hawaii starting this afternoon and continuing through Sunday as a large area of moisture associated with Hone moves through. The heaviest rainfall will likely occur over windward and southeast facing slopes. 2. Tropical Storm conditions are expected on the Big Island, beginning as early as this evening and continuing through early Sunday. Winds are expected to be strongest downslope of higher terrain, over headlands, and through passes. 3. Surf associated with large swells generated by Hone will quickly build today through Sunday as Hone continues westward. Expect dangerous conditions with life-threatening surf and rip currents. FORECAST POSITIONS AND MAX WINDS INIT 24/1500Z 17.5N 151.9W 55 KT 65 MPH 12H 25/0000Z 17.8N 153.8W 55 KT 65 MPH 24H 25/1200Z 18.1N 156.0W 60 KT 70 MPH 36H 26/0000Z 18.5N 158.2W 65 KT 75 MPH 48H 26/1200Z 18.9N 160.3W 65 KT 75 MPH 60H 27/0000Z 19.2N 162.2W 60 KT 70 MPH 72H 27/1200Z 19.5N 164.0W 55 KT 65 MPH 96H 28/1200Z 20.2N 167.4W 45 KT 50 MPH 120H 29/1200Z 20.8N 170.2W 35 KT 40 MPH $$ Forecaster Jelsema/Gibbs