Atlantic Hurricane Feed

Tropical Storm Wanda Forecast Discussion



000
WTNT41 KNHC 020840
TCDAT1

Tropical Storm Wanda Discussion Number  10
NWS National Hurricane Center Miami FL       AL212021
900 AM GMT Tue Nov 02 2021

Wanda has become a little better organized since yesterday evening
with convection, albeit not very deep, now wrapping around the 
center of the storm.  Apparently the vertical shear over the 
cyclone has relaxed somewhat, and the center is now more embedded 
within the convection.  This implies that some strengthening has 
occurred and the intensity estimate is increased to 45 kt for this 
advisory.  This is also in agreement with a subjective Dvorak 
satellite estimate from SAB.  Interestingly, satellite-derived SST 
analyses indicate that Wanda is currently located over a small patch 
of warmer ocean waters, near 25 deg C.

The storm is moving a little faster toward the east-northeast, or 
at about 060/7 kt.  During the next couple of days, Wanda is likely 
to remain embedded within a mid-tropospheric trough .  A turn 
toward the north is expected during the next 48 to 60 hours 
while the system moves along the eastern portion of the 
trough. Later in the forecast period, a ridge building to the west 
and northwest of Wanda should force a turn toward the east and 
east-southeast.  The official forecast has been shifted to the 
right of the previous NHC track at days 4 and 5, following the 
latest dynamical model consensus.  It should be noted that the GFS 
model shows a track significantly farther south at this later time 
frame.

Although Wanda will soon be moving over cooler waters, the SHIPS, 
LGEM, and HCCA intensity guidance indicate that the system will 
strengthen a little more in the short term, and then more or less 
maintain its intensity for the next 48 hours or so.  This is 
probably due to fairly low vertical shear and relatively cool 
upper-tropospheric temperatures during this time.  Later, gradual 
weakening is likely, due to increased shear and cool waters. 
However baroclinic effects could at least partially offset the 
weakening process.  The official intensity forecast is in good 
agreement with the corrected model consensus, HCCA, solution.  
Around 72 hours, simulated satellite imagery shows a loss of 
tropical cyclone-like cloud structure so the NHC forecast indicates 
a post-tropical phase by that time.


FORECAST POSITIONS AND MAX WINDS

INIT  02/0900Z 35.0N  40.9W   45 KT  50 MPH
 12H  02/1800Z 36.1N  40.3W   50 KT  60 MPH
 24H  03/0600Z 37.8N  39.9W   50 KT  60 MPH
 36H  03/1800Z 39.8N  39.7W   50 KT  60 MPH
 48H  04/0600Z 41.6N  39.5W   50 KT  60 MPH
 60H  04/1800Z 42.6N  39.0W   45 KT  50 MPH
 72H  05/0600Z 43.0N  37.1W   45 KT  50 MPH...POST-TROPICAL
 96H  06/0600Z 41.8N  33.1W   45 KT  50 MPH...POST-TROPICAL
120H  07/0600Z 41.0N  29.4W   40 KT  45 MPH...POST-TROPICAL

$$
Forecaster Pasch



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