AXPZ20 KNHC 190326
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
245 UTC Sun Nov 19 2017
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 0000 UTC surface analysis and satellite imagery through
Gulf of Tehuantepec Gale Warning: A brief lull in northerly flow
currently in place will rapidly increase to strong to minimal
gale force around sunrise Sunday, then will continue to increase
to strong gale by Sunday night. Winds will then diminish below
gale force by Monday afternoon. Seas will build to 15 to 17 ft
during the strongest winds and will spread out away from the
source region. Looking ahead, fresh to strong drainage flow will
then persist through Tuesday morning, with more tranquil marine
conditions Tuesday afternoon through Tuesday night. Another
northerly gale force wind event is possible Wednesday through the
end of the upcoming week.
INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
The monsoon trough extends from 09N76W to 08N76W to 09N106W.
The ITCZ extends from 09N106W to 10N120W to 10N130W to 12N140W.
Scattered moderate and isolated strong convection is within an
area bounded by 13N118W to 10N116W to 07N125W to 11N126W to
13N118W, and also within an area bounded by 15N136W to 10N126W to
06N127W to 11N136W to 15N136W.
OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
See the Special Features section for information about the Gulf
of Tehuantepec Gale Warning.
A NW to SE oriented ridge just beyond 250 nm seaward will
maintain moderate to locally fresh NW flow W of Baja Peninsula
through sunrise on Sunday when the pressure gradient will relax,
supporting moderate NW flow through sunrise on Monday. Light N
winds are then expected through sunrise on Thursday.
Gulf of California: An earlier scatterometer pass indicated
fresh to near gale force NW to N winds N of 29.5N where a tight
pressure gradient is place. Fresh to strong winds will spread
southward to 25N by late tonight and seas will build to around 8
ft in the central Gulf. Winds will diminish to 20 kt or less by
late Sunday night as the pressure gradient relaxes. Moderate
northerly flow is anticipated across the entire Gulf waters by
Sunrise on Monday, becoming light Monday night.
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND
WITHIN 750 NM OF ECUADOR...
Gulf of Papagayo: Moderate to locally fresh NE drainage winds
are forecast during the overnight hours through the middle of the
upcoming week with seas building to 5 to 6 ft downstream near
Light and variable winds and 3 to 5 ft seas are expected
elsewhere to the N of 09N, while moderate to locally fresh
southerly winds and 4 to 7 ft seas are forecast S of 09N through
the middle of the upcoming week.
REMAINDER OF THE AREA...
A NE to SW aligned ridge builds from 32N124W to beyond 20N140W.
Fresh to locally strong southerly flow will develop across the NW
corner of the discussion waters tonight as the pressure gradient
tightens between the ridging and a cold front W of the area.
Meanwhile associated convection with the front is already
spreading E of 140W, currently N of 17N and W of 132W. Seas
will gradually build to 8 to 10 ft by early Sunday afternoon.
These winds will continue through Sunday, possibly approaching
near gale force near 30N140W with seas building to up to 12 ft.
The fresh to strong winds will then finally diminish by the
middle of the upcoming week. The ridging will hold strong helping
to keep the front W of the area with it likely stalling and
eventually dissipating W of 140W.
Elsewhere, an area of fresh trades is supporting 8 to 9 ft in
mixed swell from 13N to 18N between 129W and 137W. These trades
should relax somewhat by early Sunday afternoon allowing for the
seas to decay to less than 8 ft.