subj/prognostic reasoning for tropical storm 24w warning nr 28// rmks/ 1. For meteorologists. 2. 12 hour summary and analysis. A. Tropical Storm (TS) 24w (Mitag) was downgraded to ts strength on the 26/18z warning based on a rapidly weakening system with dvorak intensity estimates of 55 to 65 knots. The system continues to weaken due primarily to strong southerly vertical wind shear of 40-50 knots associated with an approaching midlatitude shortwave and dvorak estimates have decreased to 45 to 55 knots. B. Animated multispectral imagery depicts an apparent low-level circulation center (LLCC) becoming partially exposed over the past 06 hours but difficult to clearly discern at this time. A 262208z Quikscat depicts a well-defined LLCC that corresponds fairly well to recent radar fixes from kaohsiung, Taiwan. Additionally, surface observations from 981320 (20.8n 121.8e) indicated 090/12-15 knots with slp near 1002 mb. This data supported the current storm position. 3. Forecast reasoning a. The forecast track has been changed significantly due inh large part to the rapid weakening of the system as it moved under strong vertical wind shear of 40-50 knots. B. Ts 24w is tracking east-northeastward and appears to have slowed. Positioning remains difficult leading to low confidence in the current motion. Recent radar data indicates system may be moving eastward to east-southeastward or exhibiting quasi-stationary movement. The current forecast track continues to track the system above the ridge axis under the westerly flow leading to extra- tropical transition. The available dynamic aids are now in poor agreement and indicate a northeastward to southward track with varying track speeds. This forecast is positioned slightly slower and south of the consensus based on the rapid weakening and radar fixes indicating a possible slow-down. It is possible this system may weaken and become quasi-stationary over the next 06-12 hours and this scenario will be closely monitored as well using visible imagery. Forecast team: Bravo//