je.st
news
Tropical Storm Kenneth Forecast Discussion Number 20
2017-08-23 10:35:26| National Hurricane Center (East Pacific)
Issued at 200 AM PDT Wed Aug 23 2017 000 WTPZ43 KNHC 230835 TCDEP3 Tropical Storm Kenneth Discussion Number 20 NWS National Hurricane Center Miami FL EP132017 200 AM PDT Wed Aug 23 2017 Conventional satellite imagery shows continued deterioration of Kenneth's cloud pattern. A moderate southwesterly wind shear regime and oceanic temperatures of less than 24.5C have certainly taken its toll on the cyclone. A compromise of the subjective and objective intensity estimates is the basis of lowering the initial intensity to 50 kt for this advisory. The aforementioned shear and cool water, along with a continued intruding stable air mass from the north, should result in a gradual spin down of Kenneth with weakening to a remnant low in about 24 hours, and dissipation in 5 days. The official intensity forecast follows the IVCN and Decay-SHIPS models, and reflects the previous advisory's weakening trend. The initial motion is estimated to be north-northwestward, or 340/9 kt. Kenneth should continue to move north-northwestward during the next 36-48 hours in a break in a subtropical ridge created by a high amplitude upper-level trough extending northeastward from the eastern Hawaiian Islands. Afterward, the cyclone is forecast to degenerate to a vertically shallow remnant low and move within the lower tropospheric southeasterly flow. There is some increasing spread in the global models beyond day 3. The UKMET and GFS indicate a more accelerated rate of weakening than the ECMWF. Consequently, the weaker Kenneth reflected in the UKMET/GFS decreases significantly in forward speed and turns west-northwestward in the shallow steering current while a more vertically coherent cyclone in the ECMWF continues northwestward with little reduction in speed. The NHC track forecast is a blend of both of these solutions and is very close to the HFIP Corrected Consensus model. FORECAST POSITIONS AND MAX WINDS INIT 23/0900Z 23.5N 134.3W 50 KT 60 MPH 12H 23/1800Z 24.8N 135.0W 40 KT 45 MPH 24H 24/0600Z 26.4N 135.8W 30 KT 35 MPH...POST-TROP/REMNT LOW 36H 24/1800Z 27.6N 136.1W 25 KT 30 MPH...POST-TROP/REMNT LOW 48H 25/0600Z 28.4N 136.4W 25 KT 30 MPH...POST-TROP/REMNT LOW 72H 26/0600Z 29.4N 137.3W 20 KT 25 MPH...POST-TROP/REMNT LOW 96H 27/0600Z 30.4N 138.9W 20 KT 25 MPH...POST-TROP/REMNT LOW 120H 28/0600Z...DISSIPATED $$ Forecaster Roberts
Tags: number
discussion
storm
tropical
Category:Transportation and Logistics