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| #1094294 (Received by flhurricane at: 4:51 PM 05.Jun.2022) TCDAT1 Tropical Storm Alex Discussion Number 13 NWS National Hurricane Center Miami FL AL012022 500 PM EDT Sun Jun 05 2022 Earlier this afternoon, an Air Force Reserve Hurricane Hunter aircraft reported reliable-looking SFMR winds of 50-55 kt near the center of Alex, and 700-mb flight-level winds of up to 77 kt in the southeastern quadrant. The central pressure was near 991 mb. Based on these data, the initial intensity is set to 55 kt. While Alex continues to generate a cluster of convection close to the center in the northeastern quadrant, overall the cyclone looks a little less tropical than it did this morning. This is likely due to entrainment of upper-level cool/dry air from a trough just west of the cyclone. Alex has likely peaked in intensity, as the system is moving toward cooler water and the divergent outflow caused by the aforementioned upper-level trough is decreasing. Steady weakening is forecast after 12 h, and Alex is now forecast to become extratropical by 36 hr as it merges with a frontal system. After that, most of the numerical weather prediction models forecast the system to decay quickly and weaken to a trough between 72-96 h, and the official forecast follows this scenario. However, an alternative scenario comes from the UKMET and the HMON, which show the cyclone becoming a strong extratropical low that continues quickly northeastward into the northeastern Atlantic. The initial motion is now 060/24 kt. A general east-northeastward motion is expected during the next 24 h or so, with the center of Alex passing north of Bermuda on Monday. After that, the majority of the dynamical models forecast Alex to turn eastward and slow its forward speed as it finishes extratropical transition and becomes a shallow and elongated vortex, and the forecast track follows that scenario instead of the UKMET/HMON scenario. The new forecast track is slightly faster than the previous track through 24 h, then is a little slower than the previous track thereafter. The new forecast is in best agreement with the GFS model, and after 36 h it lies to the south of the various consensus models. KEY MESSAGES: 1. Alex is forecast to pass near or just north of Bermuda on Monday, and tropical storm conditions are expected on the island late tonight and Monday. FORECAST POSITIONS AND MAX WINDS INIT 05/2100Z 31.5N 71.5W 55 KT 65 MPH 12H 06/0600Z 32.6N 68.0W 55 KT 65 MPH 24H 06/1800Z 33.9N 63.2W 50 KT 60 MPH 36H 07/0600Z 34.8N 58.6W 45 KT 50 MPH...POST-TROP/EXTRATROP 48H 07/1800Z 35.0N 54.6W 40 KT 45 MPH...POST-TROP/EXTRATROP 60H 08/0600Z 35.1N 51.3W 35 KT 40 MPH...POST-TROP/EXTRATROP 72H 08/1800Z 35.7N 48.5W 30 KT 35 MPH...POST-TROP/EXTRATROP 96H 09/1800Z...DISSIPATED $$ Forecaster Beven |
