Tropical Storm Patty Forecast Discussion Number 8
Issued at 300 AM GMT Mon Nov 04 2024 000 WTNT42 KNHC 040236 TCDAT2 Tropical Storm Patty Discussion Number 8 NWS National Hurricane Center Miami FL AL172024 300 AM GMT Mon Nov 04 2024 Patty has continued producing deep convection since the time of the previous advisory, although the convective structure has recently degraded slightly on the latest infrared images. The infrared satellite images and an 03/2138 UTC ASCAT pass depict a more compact cyclone with a confined radius of maximum winds than earlier in the system's life. Patty is also no longer co-located with the upper-level low that was earlier responsible for its hybrid characteristics. Based on these observations, Patty has made the transition into a tropical storm. The earlier ASCAT pass showed tropical storm force winds as high as 39 kt in the southern semicircle. The initial intensity is therefore held at 40 kt. The initial motion of the tropical storm is estimated to be eastward, or 085/17 kt. Patty is expected to turn east-northeastward over the next day, and only a slight northward adjustment was made to the previous forecast, closer to the latest track consensus guidance. All guidance insists Patty will weaken significantly during the next day or two as the cyclone encounters progressively colder sea-surface temperatures, stronger vertical wind shear and drier air. Although the timing of when Patty is forecast to lose its convection and become post-tropical has been pushed back slightly, confidence is fairly high that the system will be falling apart and weakening in a day or two. The various global models agree that Patty should open up into a trough and dissipate by hour 48, around the time that the circulation reaches the west coast of the Iberian Peninsula. Due to orographic lifting, some rainfall impacts appear possible for portions of Portugal and Spain from Patty's remnants. Key messages: 1. Between late Monday and Tuesday, heavy rainfall across portions of Portugal and western Spain is possible from Patty or its remnants. FORECAST POSITIONS AND MAX WINDS INIT 04/0300Z 37.7N 20.0W 40 KT 45 MPH 12H 04/1200Z 38.4N 16.7W 40 KT 45 MPH 24H 05/0000Z 39.8N 12.8W 35 KT 40 MPH...POST-TROPICAL 36H 05/1200Z 41.0N 10.0W 30 KT 35 MPH...POST-TROP/REMNT LOW 48H 06/0000Z...DISSIPATED $$ Forecaster Hagen
Issued at 300 AM GMT Mon Nov 04 2024
000 WTNT42 KNHC 040236 TCDAT2 Tropical Storm Patty Discussion Number 8 NWS National Hurricane Center Miami FL AL172024 300 AM GMT Mon Nov 04 2024 Patty has continued producing deep convection since the time of the previous advisory, although the convective structure has recently degraded slightly on the latest infrared images. The infrared satellite images and an 03/2138 UTC ASCAT pass depict a more compact cyclone with a confined radius of maximum winds than earlier in the system's life. Patty is also no longer co-located with the upper-level low that was earlier responsible for its hybrid characteristics. Based on these observations, Patty has made the transition into a tropical storm. The earlier ASCAT pass showed tropical storm force winds as high as 39 kt in the southern semicircle. The initial intensity is therefore held at 40 kt. The initial motion of the tropical storm is estimated to be eastward, or 085/17 kt. Patty is expected to turn east-northeastward over the next day, and only a slight northward adjustment was made to the previous forecast, closer to the latest track consensus guidance. All guidance insists Patty will weaken significantly during the next day or two as the cyclone encounters progressively colder sea-surface temperatures, stronger vertical wind shear and drier air. Although the timing of when Patty is forecast to lose its convection and become post-tropical has been pushed back slightly, confidence is fairly high that the system will be falling apart and weakening in a day or two. The various global models agree that Patty should open up into a trough and dissipate by hour 48, around the time that the circulation reaches the west coast of the Iberian Peninsula. Due to orographic lifting, some rainfall impacts appear possible for portions of Portugal and Spain from Patty's remnants. Key messages: 1. Between late Monday and Tuesday, heavy rainfall across portions of Portugal and western Spain is possible from Patty or its remnants. FORECAST POSITIONS AND MAX WINDS INIT 04/0300Z 37.7N 20.0W 40 KT 45 MPH 12H 04/1200Z 38.4N 16.7W 40 KT 45 MPH 24H 05/0000Z 39.8N 12.8W 35 KT 40 MPH...POST-TROPICAL 36H 05/1200Z 41.0N 10.0W 30 KT 35 MPH...POST-TROP/REMNT LOW 48H 06/0000Z...DISSIPATED $$ Forecaster Hagen
