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Tropical Storm BLANCA

Tropical Storm Blanca Discussion Number  11
NWS National Hurricane Center Miami FL       EP022021
300 AM MDT Wed Jun 02 2021
Recent satellite imagery indicates southwesterly vertical wind shear 
continues to impinge on the western side of Blanca's circulation. 
The coldest cloud tops are displaced to the east of the estimated 
center, and deep convection is becoming more limited in coverage. 
GMI microwave data from 0450 UTC suggest the cyclone's low-level 
circulation is losing some definition and may contain multiple 
centers. Unfortunately, none of the overnight scatterometer passes 
sampled the core of Blanca, although a recent ASCAT-A pass shows 
several 30-32 kt wind vectors in the eastern semicircle over 60 n mi 
from the center. The initial intensity is decreased to 40 kt with 
this advisory, which falls between the subjective Dvorak estimates 
from SAB (35 kt) and TAFB (45 kt) and is consistent with the latest 
UW-CIMSS ADT current intensity estimate.
Environmental conditions along Blanca's forecast track should 
maintain the current weakening trend through the forecast period. 
This includes stronger vertical wind shear over the next few days 
associated with a mid- to upper-level low near Baja California, in 
addition to decreased oceanic heat content and a drier, more stable 
environment aloft. The official NHC intensity forecast closely 
follows the intensity consensus aid (IVCN), and Blanca is expected 
to become a tropical depression by Thursday and a remnant low this 
The cyclone continues to turn more westward and slow down under 
weakening steering currents, and its estimated motion is now an 
uncertain 285/5 kt. A general westward motion is expected during the 
next several days as the weakening cyclone is largely steered by the 
low-level easterly trades. Based on a noticeable southward shift in 
much of the guidance including the HFIP corrected consensus (HCCA), 
the latest NHC track forecast is adjusted left of track from the 
previous one and lies closer to the TVCE consensus aid.
INIT  02/0900Z 15.0N 112.0W   40 KT  45 MPH
 12H  02/1800Z 15.1N 112.5W   35 KT  40 MPH
 24H  03/0600Z 15.3N 113.3W   35 KT  40 MPH
 36H  03/1800Z 15.3N 114.0W   30 KT  35 MPH
 48H  04/0600Z 15.3N 115.1W   30 KT  35 MPH
 60H  04/1800Z 15.2N 116.2W   25 KT  30 MPH
 72H  05/0600Z 15.1N 117.5W   25 KT  30 MPH
 96H  06/0600Z 15.5N 119.5W   25 KT  30 MPH...POST-TROP/REMNT LOW
120H  07/0600Z 16.0N 121.0W   20 KT  25 MPH...POST-TROP/REMNT LOW
Forecaster Reinhart/Beven