459 WTPZ43 KNHC 171437 TCDEP3 Tropical Storm Lester Discussion Number 8 NWS National Hurricane Center Miami FL EP132022 1000 AM CDT Sat Sep 17 2022 Lester's overnight improvement in organization was short lived. Several microwave overpasses during the last few hours show a distinct lack of organized convective banding, and little evidence that a well-defined circulation still exists. It is possible that close proximity to land has severely disrupted Lester's structure since it has been very difficult to locate the cyclone's center in traditional IR or Visible imagery this morning. With the center of Lester well-hidden below higher clouds, the uncertainty in the initial position and motion are unusually high, which also translates to high uncertainty in the intensity estimate since the Dvorak technique is very dependent on center location. The initial intensity of 35 kt is based on a blend of recent Dvorak fixes, but should be considered within that uncertain context. Significant strengthening is not supported by any guidance and appears unlikely with Lester so close to land, so the biggest threat will be very heavy rain leading to flash and urban flooding across portions of the southwest coast of Mexico. Mudslides will also be possible in areas of high terrain. That threat will exist over a wide area regardless of Lester's position or intensity, and will persist today even after Lester dissipates. Users are therefore urged to not put much weight into the specifics of the NHC track and intensity forecasts, which shows Lester moving inland and dissipating later today. This scenario is supported by all of the dynamical models, with some (like the ECMWF, UKMET and CMC models) indicating that Lester may have already moved inland. Key Messages: 1. Heavy rains from Lester will continue for portions of coastal southern Mexico into Sunday. This rainfall may produce flash and urban flooding, along with possible mudslides in areas of higher coastal terrain. 2. Tropical storm conditions are possible along portions of the coast of southwestern Mexico today. FORECAST POSITIONS AND MAX WINDS INIT 17/1500Z 16.0N 99.0W 35 KT 40 MPH 12H 18/0000Z 17.3N 99.9W 25 KT 30 MPH...POST-TROP/INLAND 24H 18/1200Z...DISSIPATED $$ Forecaster D. Zelinsky