Tropical Storm Oscar Discussion Number 6
NWS National Hurricane Center Miami FL AL162018
500 AM AST Sun Oct 28 2018

Deep convection near the center of Oscar has diminished somewhat
over the past several hours. However, there are tightly curved
cloud bands very near the center indicating a well-organized
cyclone. Given that the central convection has not increased, the
current intensity estimate is held at 55 kt which is a little above
the latest subjective and objective Dvorak estimates but close to
the value indicated by the previous scatterometer data. Oscar
should remain in a moderate vertical shear environment, and over
26-27 deg C SSTs, for the next couple of days which would allow for
some strengthening. The official forecast is close to the latest
intensity model consensus and calls for the system to become a
hurricane soon. Near or just beyond 96 hours, the shear is forecast
to increase substantially and Oscar should begin to make the
transition to an extratropical cyclone.

The storm has been moving southwestward, or 235/13 kt, on the
southeastern side of a northeast to southwest-oriented mid-level
ridge. The ridge is likely to build to the north of Oscar within
12 to 24 hours, resulting in a turn toward the west. The cyclone
should then turn toward the northwest and north as the ridge shifts
eastward and a trough moves off the eastern U.S. coast. In the
latter half of the forecast period, the system should accelerate
north-northeastward to northeastward in the flow ahead of the
trough. The official track forecast is close to the latest
dynamical model consensus, and similar to the previous NHC track.

FORECAST POSITIONS AND MAX WINDS

INIT 28/0900Z 25.0N 52.6W 55 KT 65 MPH
12H 28/1800Z 25.0N 54.5W 65 KT 75 MPH
24H 29/0600Z 25.5N 56.7W 70 KT 80 MPH
36H 29/1800Z 26.4N 58.0W 75 KT 85 MPH
48H 30/0600Z 27.9N 58.0W 75 KT 85 MPH
72H 31/0600Z 34.6N 53.6W 75 KT 85 MPH
96H 01/0600Z 42.5N 44.5W 60 KT 70 MPH
120H 02/0600Z 50.0N 28.5W 55 KT 65 MPH…POST-TROP/EXTRATROP

$$
Forecaster Pasch

 

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 AM PDT Sun Oct 28 2018

For the eastern North Pacific…east of 140 degrees west longitude:

1. Showers and thunderstorms associated with a small well-defined low
pressure system located several hundred miles south-southwest of
Acapulco, Mexico have increased during the past few hours. Some
additional development of this system is possible and a tropical
depression could form during the next couple of days while it moves
westward at about 10 mph.
* Formation chance through 48 hours…medium…40 percent.
* Formation chance through 5 days…medium…40 percent.

2. An area of low pressure located about 1000 miles south-southwest of
the southern tip of the Baja California peninsula is producing
limited shower activity. Some slow development of this system is
possible over the next several days while the low moves toward the
west or west-northwest at about 10 mph.
* Formation chance through 48 hours…low…10 percent.
* Formation chance through 5 days…low…20 percent.

Forecaster Zelinsky

Global Tropics & Benefits Outlook

Weather in Cayman

SYNOPSIS