je.st
news
Tropical Storm Kevin Forecast Discussion Number 15
2021-08-11 04:36:17| National Hurricane Center (East Pacific)
Issued at 800 PM PDT Tue Aug 10 2021 000 WTPZ41 KNHC 110236 TCDEP1 Tropical Storm Kevin Discussion Number 15 NWS National Hurricane Center Miami FL EP112021 800 PM PDT Tue Aug 10 2021 Tracking the center of Kevin this evening has been a challenge, as multiple low-level swirls appear to be rotating cyclonically around a broader mean circulation. The deeper convection remains mostly south of the estimated circulation center, though some cooler cloud tops did attempt to build northward, following a mesovortex seen on visible satellite imagery. Subjective Dvorak intensity estimates from SAB and TAFB at 0000 UTC were T2.5/35 kt and T3.0/45 kt, respectively, and the latest UW-CIMSS SATCON estimate was hovering between these values at 42 kt. The initial intensity is held at 45 kt for this advisory, favoring the higher intensity estimates given the earlier ASCAT data. The initial motion is estimated at 315/7 kt, attempting to follow the mean center that has several mesovorticies rotating around. A general northwest to west-northwestward motion is expected to continue over the next several days as the large cyclone is steered by a deep-layer ridge located to its northeast. The latest track guidance was a bit more poleward compared to the previous cycle, and the latest NHC track forecast has been shifted a bit more poleward in the short term, choosing to remain close to the track guidance consensus. Moderate to strong northeasterly wind shear continues to keep Kevin's deepest convection downshear in the southern semicircle of the large circulation envelope. Over the next 24 hours, Kevin will also be crossing a sharp sea-surface temperature (SST) gradient, with sub 26 C SSTs not far away to the north. As the cyclone moves over these progressively cooler waters, gradual weakening should commence. Simulated IR brightness temperature data from both the GFS and ECMWF suggest that Kevin will lose its remaining organized convection by 48-60 hours, and the latest NHC intensity forecast shows Kevin becoming a remnant low by that time. FORECAST POSITIONS AND MAX WINDS INIT 11/0300Z 19.5N 115.4W 45 KT 50 MPH 12H 11/1200Z 20.7N 116.5W 40 KT 45 MPH 24H 12/0000Z 21.9N 118.3W 35 KT 40 MPH 36H 12/1200Z 23.0N 120.3W 30 KT 35 MPH 48H 13/0000Z 24.0N 122.5W 25 KT 30 MPH 60H 13/1200Z 25.1N 124.7W 25 KT 30 MPH...POST-TROP/REMNT LOW 72H 14/0000Z 26.3N 126.8W 25 KT 30 MPH...POST-TROP/REMNT LOW 96H 15/0000Z 28.4N 130.0W 20 KT 25 MPH...POST-TROP/REMNT LOW 120H 16/0000Z...DISSIPATED $$ Forecaster Papin/Stewart
Tags: number
discussion
kevin
storm
Category:Transportation and Logistics