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. 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.
The new forecast track is slightly faster than the previous track through 24 h, then is a little slower than the previous track thereafter. 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. 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. 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. 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. 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. 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. This is likely due to entrainment of upper-level cool/dry air from a trough just west of the cyclone.
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. Based on these data, the initial intensity is set to 55 kt.
Issued at 500 PM EDT Sun 000 WTNT41 KNHC 052039 TCDAT1 Tropical Storm Alex Discussion Number 13 NWS National Hurricane Center Miami FL AL012022 500 PM EDT Sun 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.
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