000
WTPZ42 KNHC 090235
TCDEP2
 
Tropical Storm Barbara Discussion Number   4
NWS National Hurricane Center Miami FL       EP022025
900 PM CST Sun Jun 08 2025

After a marked decrease in deep convection a few hours ago, 
thunderstorm activity is now increasing near the center of the 
storm, with a comma-shaped pattern evolving.  A recent GPM 
microwave overpass suggested that the inner core structure is 
becoming a little better defined.  Subjective Dvorak intensity 
estimates are 55 kt from both TAFB and SAB, and this is used for 
the advisory intensity.  This is also in agreement with a blend of 
the various objective intensity estimates based on both 
geostationary and limited microwave imagery.

Although there is some scatter in the center fixes, the overall 
motion appears to be west-northwestward at around 300/9 kt.  
Though some of the track guidance suggests a more northwestward 
motion during the next few days, there should be enough of a ridge 
to the north of Barbara to prevent a significant northward turn 
during the next 48-72 hours.  In fact the GFS model, which appears 
to have the most realistic and about the strongest initialization 
for the system, is on the left side of the guidance envelope.  The 
official forecast has been shifted to the right of the previous one 
based on the model consensus, but leans toward the GFS solution.  By 
72-96 hours, Barbara should be reduced to a remnant low and move 
generally westward following the low-level flow.

Barbara is currently over warm waters within an environment of 
low vertical wind shear and high atmospheric moisture.  These 
factors should result in the cyclone strengthening into a hurricane 
very soon, and the NHC prediction is above almost all of the 
guidance.  In a day or so, cooler SSTs are expected to cause a 
weakening trend to begin.  The model guidance is in good agreement 
on Barbara weakening into a tropical depression in 60-72 hours, and 
this is also shown in the official forecast.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  09/0300Z 16.5N 104.9W   55 KT  65 MPH
 12H  09/1200Z 17.2N 106.1W   65 KT  75 MPH
 24H  10/0000Z 18.3N 107.4W   70 KT  80 MPH
 36H  10/1200Z 19.3N 108.5W   60 KT  70 MPH
 48H  11/0000Z 20.2N 109.5W   45 KT  50 MPH
 60H  11/1200Z 20.5N 110.5W   30 KT  35 MPH
 72H  12/0000Z 20.5N 111.4W   25 KT  30 MPH...POST-TROP/REMNT LOW
 96H  13/0000Z 20.5N 112.5W   20 KT  25 MPH...POST-TROP/REMNT LOW
120H  14/0000Z...DISSIPATED
 
$$
Forecaster Pasch