satellite images and surface observations indicate the the area of
disturbed weather southeast of Acapulco is now a tropical
depression. Banding features are becoming more prominent...
although the low-level center appears to be on the eastern side of
the deep convection. Dvorak intensity estimates from
TAFB/SAB are 30 kt...and that will be the initial intensity. A
ship report at 1700 UTC of 41 kt does not appear to be
representative of the intensity of the system.
The future intensification of the depression will likely be dictated
by how close the system gets to land and the strength of the
persistent easterly shear that has characterized the eastern Pacific
during most of the season. The majority of the track guidance keeps
the system offshore but relatively close to southwestern Mexico.
The SHIPS model shows rapid strengthening...to 101 kt in 72
hours...assuming the system stays offshore. However the GFDL/hwrf
do not intensify the system very much even though they keep the
system over water. The NHC intensity forecast will stay on the
conservative side for now...but a little higher than a consensus of
the SHIPS/GFDL/hwrf models.
The best estimate of initial motion is 310/7. There is a weakness
in the subtropical ridge over the western Gulf of Mexico that should
allow the system to move northwestward for a day or so.
Thereafter...a track more toward the west-northwest is
anticipated as the depression becomes steered by weak
ridging over northwestern Mexico. The official track forecast is
near but a little faster than the numerical model consensus. It is
notable that guidance is in poor agreement beyond 3 days.
