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| #1094373 (Received by flhurricane at: 5:08 AM 06.Jun.2022) TCDAT1 Tropical Storm Alex Discussion Number 15 NWS National Hurricane Center Miami FL AL012022 500 AM AST Mon Jun 06 2022 Alex is looking increasingly less like a tropical cyclone and more like a post-tropical entity. While the low-level circulation is clearly evident on conventional satellite imagery, it is largely devoid of deep central convection, with the nearest cold cloud tops below -60C located more than 200 nm to the northeast. Those well removed colder cloud tops are forming in response to a digging mid-latitude trough that will ultimately lead to Alex`s demise. In the meantime, there was a convective band east of Alex that produced tropical-storm-force winds over Bermuda this morning, and these winds will likely continue until the center passes by to the north later today. Earlier Air Force reconnaissance aircraft found flight level winds that still supported an intensity of 60 kt at 0600 UTC. However, assuming some weakening has occurred since then given the current lack of convection near the center, the initial intensity has been reduced to 55 kt for this advisory. Alex is expected to continue moving over cooler waters in an environment of increasing vertical wind shear and dry mid-latitude air, and the cyclone is likely to become extratropical or a remnant low later today. Beyond 36 hours, the GFS and ECMWF forecast an upstream mid-latitude trough to spawn a new surface baroclinic cyclone northeast of Alex, causing the former tropical cyclone to be absorbed at the end of the forecast period. The current NHC intensity forecast is similar to the previous advisory, though it now moves up extratropical transition to later today. Alex continues to move briskly to the east-northeast at 065/24 kt. The cyclone should remain on this general heading over the next 36 hours or so before it is absorbed. Once again the forecast this cycle is a bit faster than the previous one, blending the consensus aids and an average between the operational GFS and ECMWF runs (GFEX). KEY MESSAGES: 1. Alex is forecast to pass near or just north of Bermuda today, and tropical storm conditions are expected on the island through this afternoon. FORECAST POSITIONS AND MAX WINDS INIT 06/0900Z 33.5N 66.7W 55 KT 65 MPH 12H 06/1800Z 34.7N 62.7W 45 KT 50 MPH...POST-TROP/EXTRATROP 24H 07/0600Z 36.7N 56.5W 45 KT 50 MPH...POST-TROP/EXTRATROP 36H 07/1800Z 39.5N 49.8W 45 KT 50 MPH...POST-TROP/EXTRATROP 48H 08/0600Z...ABSORBED BY EXTRATROPICAL LOW $$ Forecaster Papin/Blake |