TROPICAL STORM 08E KST Advisory Number 2
KST HQ CEBU, PHILIPPINES
Tropical Storm Hilda [EP082021]
0900UTC SAT JULY 31 2021
...HILDA STRENGTHENING... ...FORECAST TO BECOME A HURRICANE BY TONIGHT OR EARLY SUNDAY...
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SUMMARY OF INFORMATION
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LOCATION...13.3N 115.7W
ABOUT 765 MI...1230 KM SSW OF THE SOUTHERN TIP OF BAJA CALIFORNIA
MAXIMUM SUSTAINED WINDS...50 MPH...85 KM/H
PRESENT MOVEMENT...WNW OR 290 DEGREES AT 14 MPH...22 KM/H
MINIMUM CENTRAL PRESSURE...1002 MB...29.59 INCHES
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WATCHES AND WARNINGS
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There are no warnings and watches associated with Tropical Storm Hilda
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KEY MESSAGES
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There are currently no Key Messages for Tropical Storm Hilda
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DISCUSSION
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A prominent convective band now wraps about halfway around the
southeast to west side of Hilda's center, and another band is
taking shape to the north of the center. With the improved
organization, Dvorak estimates increased to a consensus T3.0/45 kt
from TAFB and SAB, and a 0520 UTC ASCAT-B pass confirmed that indeed
maximum winds are about 45 kt. This is being set as Hilda's
initial intensity, although it could be a little conservative since
objective ADT estimates have trended higher than that since 0600
UTC.
A mid-tropospheric ridge currently extends from northern Mexico
westward across the Baja California peninsula to about 120W and is
steering Hilda west-northwestward at 290/12 kt. Although this
ridge is expected to build westward and keep Hilda on a
west-northwestward course, potential interactions with Tropical
Depression Nine-E to the west and another low pressure area to the
east could cause the storm to slow down over the next 3 days and
oscillate a bit around that general heading. There is slightly more
spread among the track models than is typical, with the HWRF a
notable southern outlier and the GFS and HMON models having some of
the faster solutions due to greater interaction with T.D. Nine-E.
That being said, the overall track guidance has trended a little
slower and farther south on this cycle, and the updated NHC track
forecast has therefore been adjusted in that direction from the
previous forecast, lying close to the TVCE multi-model consensus but
not nearly as far south as the HCCA consensus aid.
Hilda is currently in a light-shear regime and over sea surface
temperatures of about 29 degrees Celsius, so continued
strengthening is anticipated in the short term with Hilda likely
to reach hurricane strength by tonight or early Sunday. However,
global models are suggesting that the shear may increase out of the
east during the next 24 hours, and then Hilda will be near cooler
waters in 2 to 3 days. Therefore, Hilda is likely to reach its
peak intensity in about 48 hours, and the NHC intensity forecast at
that time is near the upper end of the guidance suite. Hilda is
expected to move over even cooler waters after 48 hours, which
should cause a gradual weakening trend through the end of the
forecast period.
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FORECAST CONE
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FORECAST POSITIONS AND MAX WINDS
INIT 31/0900Z 13.3N 115.7W 45 KT 50 MPH
12H 31/1800Z 13.6N 117.3W 55 KT 65 MPH
24H 01/0600Z 14.1N 119.1W 65 KT 75 MPH
36H 01/1800Z 14.6N 120.8W 70 KT 80 MPH
48H 02/0600Z 15.1N 122.3W 75 KT 85 MPH
60H 02/1800Z 15.7N 123.7W 70 KT 80 MPH
72H 03/0600Z 16.3N 124.8W 65 KT 75 MPH
96H 04/0600Z 17.8N 127.6W 55 KT 65 MPH
120H 05/0600Z 18.9N 131.5W 45 KT 50 MPH
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INFORMATION FROM THE NATIONAL HURRICANE CENTER
$$
FORECASTER KHAN/BERG