Tropical Storm Xavier Discussion Number 12
NWS National Hurricane Center Miami FL EP252018
800 AM MST Mon Nov 05 2018
A burst of deep convection occurred over the low-level center
around the time of the last advisory, but that activity has again
been scoured off to the northeast due to 30 kt of southwesterly
shear. Satellite intensity estimates have not changed, and the
initial intensity remains 50 kt, which is very close to the latest
UW-CIMSS ADT and SATCON estimates. Xavier has been tenaciously
resisting the ill effects of shear for the time being. However,
the circulation will be moving westward toward a drier environment
where mid-level relative humidity values are 30-40 percent. In
theory, the combination of strong shear and drier air should put an
end to deep convection production, but relatively warm waters could
still allow the cyclone to produce intermittent bursts of shower and
thunderstorm activity over the next several days. Based on the
latest intensity guidance, no changes were made to the official
forecast, which continues to show Xavier becoming a remnant low in
48 hours and dissipating by day 4.
Caught within a break in the subtropical ridge, Xavier is only
creeping west-northwestward, or 295/3 kt. As deep convection
gradually dwindles near the cyclone, the shallower circulation is
expected to be steered westward to the south of a low-level ridge
stretching across northern Mexico and the Baja California
peninsula. The new NHC track forecast is nearly identical to the
previous one during the first 24 hours. After 24 hours, it has
been nudged southward toward the various consensus aids, continuing
the trend that was noted by the previous forecaster.
Even though Xavier is slowly moving away from the coast of Mexico,
inclement weather is still occurring near the coasts of Colima and
Jalisco, and tropical-storm-force winds could still be occurring
in that vicinity. Therefore, it's prudent to continue the Tropical
Storm Warning until we have confirmation that the strong winds have
shifted farther offshore.
FORECAST POSITIONS AND MAX WINDS
INIT 05/1500Z 18.5N 106.2W 50 KT 60 MPH
12H 06/0000Z 18.7N 107.0W 40 KT 45 MPH
24H 06/1200Z 18.9N 108.3W 35 KT 40 MPH
36H 07/0000Z 18.9N 109.7W 30 KT 35 MPH
48H 07/1200Z 18.8N 111.0W 25 KT 30 MPH...POST-TROP/REMNT LOW
72H 08/1200Z 18.5N 113.1W 20 KT 25 MPH...POST-TROP/REMNT LOW
96H 09/1200Z...DISSIPATED
$$
Forecaster Berg
NWS National Hurricane Center Miami FL EP252018
800 AM MST Mon Nov 05 2018
A burst of deep convection occurred over the low-level center
around the time of the last advisory, but that activity has again
been scoured off to the northeast due to 30 kt of southwesterly
shear. Satellite intensity estimates have not changed, and the
initial intensity remains 50 kt, which is very close to the latest
UW-CIMSS ADT and SATCON estimates. Xavier has been tenaciously
resisting the ill effects of shear for the time being. However,
the circulation will be moving westward toward a drier environment
where mid-level relative humidity values are 30-40 percent. In
theory, the combination of strong shear and drier air should put an
end to deep convection production, but relatively warm waters could
still allow the cyclone to produce intermittent bursts of shower and
thunderstorm activity over the next several days. Based on the
latest intensity guidance, no changes were made to the official
forecast, which continues to show Xavier becoming a remnant low in
48 hours and dissipating by day 4.
Caught within a break in the subtropical ridge, Xavier is only
creeping west-northwestward, or 295/3 kt. As deep convection
gradually dwindles near the cyclone, the shallower circulation is
expected to be steered westward to the south of a low-level ridge
stretching across northern Mexico and the Baja California
peninsula. The new NHC track forecast is nearly identical to the
previous one during the first 24 hours. After 24 hours, it has
been nudged southward toward the various consensus aids, continuing
the trend that was noted by the previous forecaster.
Even though Xavier is slowly moving away from the coast of Mexico,
inclement weather is still occurring near the coasts of Colima and
Jalisco, and tropical-storm-force winds could still be occurring
in that vicinity. Therefore, it's prudent to continue the Tropical
Storm Warning until we have confirmation that the strong winds have
shifted farther offshore.
FORECAST POSITIONS AND MAX WINDS
INIT 05/1500Z 18.5N 106.2W 50 KT 60 MPH
12H 06/0000Z 18.7N 107.0W 40 KT 45 MPH
24H 06/1200Z 18.9N 108.3W 35 KT 40 MPH
36H 07/0000Z 18.9N 109.7W 30 KT 35 MPH
48H 07/1200Z 18.8N 111.0W 25 KT 30 MPH...POST-TROP/REMNT LOW
72H 08/1200Z 18.5N 113.1W 20 KT 25 MPH...POST-TROP/REMNT LOW
96H 09/1200Z...DISSIPATED
$$
Forecaster Berg