TROPICAL STORM AGATHA DISCUSSION NUMBER 3
NWS NATIONAL HURRICANE CENTER MIAMI FL EP022016
800 AM PDT SAT JUL 02 2016
Recent SSM/I and AMSR-2 data indicate that the center of Tropical
Depression Two-E has become centrally located in the convective
overcast, and first-light visible imagery shows a large convective
burst near the center. Satellite intensity estimates at 1200Z were
30 kt from TAFB and SAB. Based on the increased organization since
that time and a recent CIMSS ADT estimate of 35 kt, the depression
is upgraded to Tropical Storm Agatha, the first named storm of the
2016 eastern Pacific hurricane season.
The initial motion is 295/10. A low- to mid-level ridge to the
north of the storm should steer it generally west-northwestward for
24 hours or so, followed by a turn toward the west. Late in the
forecast period, a turn toward the west-southwest is expected as
the remnants of Agatha come under the influence of a larger
tropical weather system to the east. The new forecast track is
shifted to the north of the previous track based on the initial
position and motion. However, it lies to the south of the various
consensus models.
Some additional strengthening is possible during the next 12-24
hours while Agatha remains in a light/moderate shear environment
over relatively warm sea surface temperatures. Beyond that time, a
combination of strong southwesterly shear and cooler sea surface
temperatures should cause a steady weakening. Agatha is expected
to weaken to a depression by 48 hours, a remnant low by 72 hours,
and dissipate completely by 120 hours.
Agatha is the latest first tropical storm in the eastern Pacific
since Ava of 1969.
TROPICAL DEPRESSION TWO-E DISCUSSION NUMBER 1
NWS NATIONAL HURRICANE CENTER MIAMI FL EP022016
800 PM PDT FRI JUL 01 2016
ASCAT data from earlier today indicated that the low pressure area
several hundred miles southwest of the Baja California peninsula had
developed a well-defined circulation. Deep convection, although
currently sheared to the west of the low-level center, has become
more organized throughout the day, and TAFB and SAB have both given
the system classifications of T1.5. Advisories are being initiated
on a new tropical depression, with the 25-kt initial intensity based
on the Dvorak estimates and ASCAT data.
The depression is moving west-northwestward, or 300/8 kt, to the
south of the subtropical ridge. The ridge is expected to remain
relatively stationary, with the cyclone forecast to continue
west-northwestward for the next couple of days. There are some
speed differences, however, with the ECMWF showing a slightly faster
motion compared with the other track models. The NHC official
forecast is a little faster than the consensus model trackers, which
did not include the ECMWF solution on this forecast cycle. After 48
hours, the weakening cyclone is expected to turn westward and then
west-southwestward by day 5.
The depression only has a small window of opportunity to strengthen.
Vertical shear is forecast to be low during the next 36 hours and
then increase significantly in 2 to 3 days. In addition, the
cyclone should move over water colder than 26 degrees Celsius and
into a much drier mid-level environment in about 36 hours.
Therefore, only modest strengthening to tropical storm strength is
shown in the NHC official forecast in the first day or two, followed
by weakening and degeneration to a remnant low by day 3.
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
140 NM EITHER SIDE OF A LINE FROM 13.8N 115.6W TO 16.9N 120.9W
WITHIN THE NEXT 12 TO 24 HOURS. AVAILABLE DATA DOES NOT JUSTIFY
ISSUANCE OF NUMBERED TROPICAL CYCLONE WARNINGS AT THIS TIME.
WINDS IN THE AREA ARE ESTIMATED TO BE 17 TO 22 KNOTS. METSAT
IMAGERY AT 011702Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 14.1N 116.0W. THE SYSTEM IS MOVING WEST-NORTHWESTWARD AT 10
KNOTS.
組圖打開中，請稍候......
