AXPZ20 KNHC 171608
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1605 UTC Wed Oct 17 2018
Tropical Weather Discussion for the eastern Pacific Ocean from
the Equator to 32N, east of 140W. The following information is
based on satellite imagery, weather observations, radar, and
Based on 1200 UTC surface analysis and satellite imagery through
Satellite-derived winds and surface observations indicate that
an elongated low pressure system has developed about 100 miles
south of Guatemala. Although associated shower and thunderstorm
activity is currently disorganized, environmental conditions are
expected to be conducive for additional development, and a
tropical depression or a tropical storm is likely to form during
the next day or two. The system is forecast to moves generally
toward the west-northwest near or just offshore the coast of
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
The monsoon trough extends 09N83W to low pres near 12N90W to
11N114W to 08N120W to 10N139W. Scattered moderate convection is
within 120 nm south of the monsoon trough E of 89W. Scattered
moderate isolated strong convection is N of 09N between 91W and
99W, and from 06N to 13N W of 127W.
OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
The remnants of Tropical Depression Tara are located near 20N
106W. Scattered moderate convection is within 75 nm NW quadrant
of the center. Strong upper level winds and interaction with the
mountainous terrain of Mexico will cause the low to weaken. It
is expected to dissipate during the next 24 hours. Heavy
rainfall will continue to impact coastal areas today.
High pressure ridge north of the area extending SSE to near the
Revillagigedo Islands is maintaining moderate to locally fresh
NW winds over the offshore forecast waters W of Baja California.
The ridge will maintain its influence over the offshore waters W
of Baja California throughout the week, yielding seas of 4-7 ft.
Fresh to strong NW winds will continue across the Gulf of
California through Friday.
A gap wind event is in the Gulf of Tehuantepec as high pressure
builds behind a stationary front in the W Gulf of Mexico. Winds
in Tehuantepec are up to 30 kt with seas building to 13 ft
within the next two days. The gap wind event will merge with the
conditions generated by the possible tropical cycone on Friday.
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND
WITHIN 750 NM OF ECUADOR...
Moderate to fresh SW monsoonal flow will continue across the
region through Wed, with active showers and thunderstorms
expected to continue across much of Central America and the
adjacent Pacific coastal waters, spreading well inland. Long
period cross-equatorial SW swell will maintain 5 to 8 ft seas
across the forecast area during the next few days. As mentioned
above, global weather models suggest the chance for low pressure
to develop offshore of the coast between Papgayo and south of
Gulf of Tehuantepec in the next few days, which will help to
focus very heavy rainfall across the region.
REMAINDER OF THE AREA...
A stationary front extending from 30N136W to 24N140W will weaken
today. Long period NW swell behind the front and cause seas to
build to between 8 and 9 ft generally N of 15N and W of 132W.
Satellite-derived wind and altimeter data indicate moderate to
fresh monsoonal flow N of 07N and south of the monsoon trough.
An area of 7 to 9 ft seas in long period SW swell is noted
between 95W and 108W, and is expected to continue across this
general area through early Thu.