000
WTPZ41 KNHC 282032
TCDEP1

Tropical Storm Alvin Discussion Number  13
NWS National Hurricane Center Miami FL       EP012019
200 PM PDT Fri Jun 28 2019

Alvin is rapidly weakening due to motion over sea surface
temperatures of 23-24C and increasing southwesterly vertical wind
shear, with the low-level center now partly exposed at the southern
edge of the weakening convective mass.  The initial intensity is
reduced to 45 kt based on a blend of recent ASCAT data and
subjective satellite intensity estimates.  Continued rapid
weakening is expected, and Alvin is forecast to become a remnant low
in about 24 h and dissipate completely after 36 h.

The initial motion is 310/13.  The cyclone should continue
generally northwestward for the next 12-18 h due to flow around a
mid-level ridge to the north.  After that time, the weakening and
increasingly shallow system should turn west-northwestward as the
low-level winds become the predominant steering mechanism.

FORECAST POSITIONS AND MAX WINDS

INIT  28/2100Z 19.7N 118.6W   45 KT  50 MPH
 12H  29/0600Z 20.7N 120.0W   35 KT  40 MPH
 24H  29/1800Z 21.5N 121.6W   25 KT  30 MPH...POST-TROP/REMNT LOW
 36H  30/0600Z 22.0N 123.1W   20 KT  25 MPH...POST-TROP/REMNT LOW
 48H  30/1800Z...DISSIPATED

$$
Forecaster Beven