Atlantic Basin Tropical Cyclones

Tropical Storm Alex Forecast Discussion


000
WTNT41 KNHC 060855
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



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