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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