ZCZC MIATCDEP2 ALL
TTAA00 KNHC DDHHMM
Tropical Storm Olivia Discussion Number 8
NWS National Hurricane Center Miami FL EP172018
300 PM MDT Sun Sep 02 2018
Olivia remains a sheared tropical cyclone with the low-level center
located to the north and northeast of the large area of deep
convection. Recent ASCAT data revealed a large area of 35-40 kt
winds over the southeastern portion of Olivia's circulation, and is
the basis for the initial wind speed of 40 kt. The global models
suggest that the northeasterly shear over the cyclone will not
abate as quickly as previous indicated, and much of the intensity
guidance shows less strengthening than before. The NHC wind speed
forecast has been lowered to be close to the intensity consensus,
but it is not as low as the statistical guidance in order to
maintain consistency with the previous official forecast. Olivia is
foreast to reach cooler waters around day 4 and the tropical
cyclone should weaken by that time.
The tropical storm is moving west-northwestward or 300/6 kt.
Olivia should turn westward as a large ridge builds to the north of
the system within the next couple of days. After midweek, Olivia
should turn back toward the west-northwest as it reaches the
western portion of the ridge. The dynamical model guidance
generally agrees with this overall scenario, but there is
cross-track spread regarding how much latitude the system
gains over the next couple of days. The NHC track is near the
various consensus aids and the GFS ensemble mean, but it is not as
far north as the latest run of the ECMWF that takes Olivia
more northwestward during the next 12 to 24 hours.
FORECAST POSITIONS AND MAX WINDS
INIT 02/2100Z 17.0N 113.4W 40 KT 45 MPH
12H 03/0600Z 17.4N 114.1W 40 KT 45 MPH
24H 03/1800Z 17.7N 115.3W 50 KT 60 MPH
36H 04/0600Z 17.9N 116.7W 60 KT 70 MPH
48H 04/1800Z 18.1N 118.6W 65 KT 75 MPH
72H 05/1800Z 19.0N 123.0W 75 KT 85 MPH
96H 06/1800Z 20.6N 128.4W 70 KT 80 MPH
120H 07/1800Z 22.3N 134.3W 60 KT 70 MPH
$$
Forecaster Brown
NNNN