Skip Navigation Links
NOAA NOAA United States Department of Commerce

Tropical Depression TWENTY-TWO-E


ZCZC MIATCDEP2 ALL
TTAA00 KNHC DDHHMM

Tropical Depression Twenty-Two-E Discussion Number   2
NWS National Hurricane Center Miami FL       EP222018
400 PM CDT Sun Oct 14 2018

Although convective activity has decreased since the previous
advisory, good cyclonic rotation is noted in the small convective
elements, and an upper-level anticyclone has developed over the
low-level center based on weak cirrus outflow now occuring in all
quadrants. A fortuitous ship located about 30 nmi west of the
center at 1800Z reported a 30-kt northerly wind and 1010.7 mb
pressure, which helped to locate the center, and also to estimate
the intensity and central pressure of the depression. The initial
intensity therefore remains 30 kt, which is supported by a satellite
intensity estimate of T2.0/30 kt from TAFB and a 1542Z ScatSat pass.

The initial motion estimate is 295/06 kt. The latest model guidance
continues the previous motion trend by only moving the cyclone
slowly westward to west-southwestward at less than 5 kt for the next
few days due to the depression remaining embedded within a break in
a deep-layer subtropical ridge that extends southwestward from
central Mexico into the eastern Pacific. A broad upper-level trough
and low located over the southwestern United States is forecast to
weaken and lift out slowly to the northeast on days 4 and 5, which
will allow the ridge to gradually build westward to the north of the
cyclone. This should result in an increase in the easterly flow
south of the ridge, helping to nudge the cyclone westward at a
slightly faster forward speed. The new NHC forecast track is a
little north of the previous advisory track after 48 h, and lies
between the consensus models TVCE and HCCA.

The cyclone is forecast to be embedded within an environment that is
somewhat conducive for at least gradual strengthening to occur. The
cyclone's small circulation and a radius of maximum winds (RMW) of
only 25-30 nmi would suggest that rapid intensification could
occur since the wind shear is expected to decrease to around 5 kt
after 36 hours. However, proximity to land is expected to
continue to disrupt the outer circulation and also create downslope
conditions off the coastal mountains, which will produce occasional
intrusions of dry air. The result is that only modest strengthening
is forecast for the next 5 days, and the official intensity
forecast is similar to a blend of the HCCA and IVCN intensity
consensus models.

The small size of the circulation and its projected motion away from
Mexico does not require tropical storm warnings or watches at this
time. However, only a slight deviation to the right of the forecast
track would bring stronger winds closer to the coast, which would
require the issuance of a tropical storm warning. Regardless of the
winds, heavy rainfall will be the primary threat along the coast of
southwestern Mexico due to the system's slow motion, and flash
flooding will be possible in mountainous areas.

FORECAST POSITIONS AND MAX WINDS

INIT  14/2100Z 17.4N 104.1W   30 KT  35 MPH
 12H  15/0600Z 17.4N 104.4W   35 KT  40 MPH
 24H  15/1800Z 17.4N 104.6W   35 KT  40 MPH
 36H  16/0600Z 17.4N 104.8W   40 KT  45 MPH
 48H  16/1800Z 17.3N 105.2W   45 KT  50 MPH
 72H  17/1800Z 17.4N 106.3W   60 KT  70 MPH
 96H  18/1800Z 17.9N 108.2W   70 KT  80 MPH
120H  19/1800Z 18.5N 108.8W   80 KT  90 MPH

$$
Forecaster Stewart

NNNN