Issued at 500 AM HST Wed Aug 28 2024
654 WTPZ43 KNHC 281433 TCDEP3 Tropical Storm Hector Discussion Number 12 NWS National Hurricane Center Miami FL EP082024 500 AM HST Wed Aug 28 2024 GOES-18 proxy-vis imagery shows that the low-level center of Hector is exposed to the southwest of a large area of deep convection. A 28/1040 UTC ATMS microwave pass also supports the analysis of the exposed center located to the southwest of the convection. An ASCAT-B pass from 28/0608 UTC showed wind vectors up to 38 kt to the north of the center. However, the ASCAT data also shows that the wind structure on the south side is becoming weak and elongated. Although the scatterometer data still shows some weak west winds on the south side, Hector could be close to opening up into a trough. Subjective current intensity estimates are 45 kt from both TAFB and SAB. Objective intensity estimates from UW-CIMSS are a bit lower, ranging from 35 to 44 kt. The initial intensity is held at 45 kt for this advisory. The center of Hector is becoming a bit more ambiguous as there appears to be a couple of weak swirls, and the best estimate of the motion is westward, or 275/9 kt. The cyclone should continue moving close to due west, steered by a low- to mid-level subtropical ridge to its north. The new NHC forecast is just a tad slower than the previous official forecast and is close to the TVCE consensus aid. Moderate west-southwesterly wind shear has already caused the convective area to be displaced well to the northeast of the center. Given that Hector is expected to continue traveling within an environment of marginal SSTs, dry air, and moderate southwesterly shear, the NHC forecast will continue to show weakening, in agreement with the latest intensity consensus guidance. Simulated satellite imagery from the GFS and ECMWF models suggests that Hector should lose its convection on Thursday, and the official forecast continues to show Hector degenerating to a remnant low at that time. Most of the global models show the remnants of Hector opening up into a trough by Friday. However, given the recent deteriorating surface wind structure observed on ASCAT and GOES-18 proxy vis imagery, it would not be surprising if Hector dissipated sooner than forecast. FORECAST POSITIONS AND MAX WINDS INIT 28/1500Z 18.3N 132.9W 45 KT 50 MPH 12H 29/0000Z 18.4N 134.5W 40 KT 45 MPH 24H 29/1200Z 18.5N 136.8W 35 KT 40 MPH 36H 30/0000Z 18.5N 139.4W 30 KT 35 MPH...POST-TROP/REMNT LOW 48H 30/1200Z 18.4N 142.3W 30 KT 35 MPH...POST-TROP/REMNT LOW 60H 31/0000Z...DISSIPATED $$ Forecaster Hagen/Reinhart/Konarik