Tropical Storm Barbara Discussion Number 24
NWS National Hurricane Center Miami FL EP022019
1100 PM HST Fri Jul 05 2019
Barbara currently consists of a swirl of low- to mid-level clouds
with isolated convective cells well north of the center. There is
a chance that the convection will increase during the next several
hours as the normal diurnal convective maximum approaches. However,
if this does not happen, the cyclone will likely be declared
post-tropical on the next advisory. The initial intensity of 45 kt
is based on recent ASCAT data.
A combination of cool sea surface temperatures, strong shear, and
mid-level dry air should cause Barbara to steadily weaken. The new
intensity forecast is similar to the previous forecast in calling
for winds to drop below tropical-storm force after 12 h, and for the
system to weaken to a trough after 48 h.
The initial motion is now 270/13. A low-level ridge to the north of
the cyclone will keep it moving generally westward with a slight
increase in speed for the next few days until Barbara dissipates.
The track guidance has shifted a little south since the last
advisory, so the new forecast track was nudged southward in
response.
FORECAST POSITIONS AND MAX WINDS
INIT 06/0900Z 18.6N 137.5W 45 KT 50 MPH
12H 06/1800Z 18.6N 139.8W 35 KT 40 MPH...POST-TROPICAL
24H 07/0600Z 18.5N 143.2W 30 KT 35 MPH...POST-TROP/REMNT LOW
36H 07/1800Z 18.3N 146.7W 25 KT 30 MPH...POST-TROP/REMNT LOW
48H 08/0600Z 18.0N 150.3W 20 KT 25 MPH...POST-TROP/REMNT LOW
72H 09/0600Z...DISSIPATED
$$
Forecaster Beven
NWS National Hurricane Center Miami FL EP022019
1100 PM HST Fri Jul 05 2019
Barbara currently consists of a swirl of low- to mid-level clouds
with isolated convective cells well north of the center. There is
a chance that the convection will increase during the next several
hours as the normal diurnal convective maximum approaches. However,
if this does not happen, the cyclone will likely be declared
post-tropical on the next advisory. The initial intensity of 45 kt
is based on recent ASCAT data.
A combination of cool sea surface temperatures, strong shear, and
mid-level dry air should cause Barbara to steadily weaken. The new
intensity forecast is similar to the previous forecast in calling
for winds to drop below tropical-storm force after 12 h, and for the
system to weaken to a trough after 48 h.
The initial motion is now 270/13. A low-level ridge to the north of
the cyclone will keep it moving generally westward with a slight
increase in speed for the next few days until Barbara dissipates.
The track guidance has shifted a little south since the last
advisory, so the new forecast track was nudged southward in
response.
FORECAST POSITIONS AND MAX WINDS
INIT 06/0900Z 18.6N 137.5W 45 KT 50 MPH
12H 06/1800Z 18.6N 139.8W 35 KT 40 MPH...POST-TROPICAL
24H 07/0600Z 18.5N 143.2W 30 KT 35 MPH...POST-TROP/REMNT LOW
36H 07/1800Z 18.3N 146.7W 25 KT 30 MPH...POST-TROP/REMNT LOW
48H 08/0600Z 18.0N 150.3W 20 KT 25 MPH...POST-TROP/REMNT LOW
72H 09/0600Z...DISSIPATED
$$
Forecaster Beven