Atlantic Basin Tropical Cyclones

Tropical Storm Earl Forecast Discussion


000
WTNT41 KNHC 060847
TCDAT1

Tropical Storm Earl Discussion Number  14
NWS National Hurricane Center Miami FL       AL062022
500 AM AST Tue Sep 06 2022

The deep convective blow-up that occurred last evening and led to 
Earl strengthening just shy of hurricane strength was quickly 
obliterated by strong shear around the issuance of the previous 
advisory.  In fact, after measuring a pressure as low as 991 mb 
early in their flight, the NOAA Hurricane Hunters reported that the 
central pressure had risen to near 998 mb based on the final 
dropsonde released near the center.  Some deep convection continues 
near and to the northeast of the estimated center, but based on the 
degraded structure from earlier, the intensity is estimated to be 55 
kt.  This value agrees with the latest Dvorak Data-T numbers from 
TAFB and SAB.

The remnant cirrus shield is obscuring the low-level center, so the 
initial position is based on interpolation from the previous 
forecast.  Earl is moving just west of due north, or 350/6 kt, and 
it should continue a slow northward path through a break in the 
subtropical ridge during the next 36 hours.  After that time, a 
deep-layer trough sliding off the U.S. east coast is expected to 
impart a faster north-northeastward and then northeastward motion 
into the upcoming weekend.  The updated NHC track forecast lies very 
close to the previous official prediction during the first 3 days, 
situated among the various multi-model consensus aids.  On days 4 
and 5, however, the new forecast is faster and to the east of the 
previous one, following the trend noted in most of the models.

UW-CIMSS and SHIPS analyses indicate that deep-layer shear over 
Earl is from the west-southwest at 30-35 kt.  Although the 
thermodynamic environment is plenty favorable for intensification, 
continued moderate to strong shear could put the breaks on 
significant strengthening until Earl turns and moves in the same 
direction as the shear vector, which should be in 2-3 days.  At 
about the same time, Earl could also benefit from a positive 
interaction with a mid- to upper-level trough located over the 
western Atlantic.  While the intensity forecast is highly 
uncertain, Earl is still expected to become a hurricane during the 
next couple of days, and possibly reach major hurricane strength in 
3-4 days.

Earl's center is expected to pass to the southeast of Bermuda in
about 3 days.  However, the size of the wind field of the tropical 
cyclone is expected to increase significantly, and interests on the 
island should continue to monitor the progress of the storm closely.


FORECAST POSITIONS AND MAX WINDS

INIT  06/0900Z 23.4N  65.4W   55 KT  65 MPH
 12H  06/1800Z 24.1N  65.7W   60 KT  70 MPH
 24H  07/0600Z 25.0N  65.7W   65 KT  75 MPH
 36H  07/1800Z 26.2N  65.5W   70 KT  80 MPH
 48H  08/0600Z 27.8N  65.0W   80 KT  90 MPH
 60H  08/1800Z 29.6N  64.3W   85 KT 100 MPH
 72H  09/0600Z 31.6N  62.7W   95 KT 110 MPH
 96H  10/0600Z 37.2N  55.5W  105 KT 120 MPH
120H  11/0600Z 42.8N  47.9W   85 KT 100 MPH

$$
Forecaster Berg



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