Tropical Weather Discussion Issued by NWS
000
AXPZ20 KNHC 102119
TWDEP
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2205 UTC Wed Apr 10 2024
Tropical Weather Discussion for the eastern Pacific Ocean from
03.4S to 30N, east of 120W including the Gulf of California, and
from the Equator to 30N, between 120W and 140W. The following
information is based on satellite imagery, weather observations,
radar, and meteorological analysis.
Based on 1800 UTC surface analysis and satellite imagery through
2100 UTC.
...SPECIAL FEATURES...
Gulf of Tehuantepec Gale Warning: The next gap wind event is
expected in the Gulf of Tehunatepec starting early on Thu as high
pressure surges southward along the eastern slopes of the Sierra
Madre Mountains in Mexico in the wake of a cold front that will
be moving across the Gulf of Mexico. Winds are forecast to increase
to minimal gale-force speeds by Thu morning. North to northeast
winds will increase further to a maximum speed of 40 kt Thu night
into Fri along with building seas expected to peak to around 16
or 17 ft. Winds then will diminish to minimal gale-force by
early Sat afternoon, and below gale force by Sat night. Large
seas generated from this strong gap wind event will spread well
away from the Tehuantepec area, with seas 8 ft or greater reaching
as far west as 104W by Fri night. Marine interests transiting
across the Gulf of Tehuantepec Fri night into Sat should be aware
of this upcoming gap wind event, and take the necessary action
to avoid hazardous marine conditions over the affected waters.
Please read the latest High Seas Forecast at
https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more
information on this event.
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
A trough extends from northern Colombia near 10N74W to 06N95W to
06N110W. The ITCZ continues from 06N110W to 05N125W and to beyond
04N140W. Scattered moderate to isolated strong convection is
noted from 04N to 10N between 81W and 89W. Similar convective
activity is observed in a about 45 nm wide band extending from
13N100W to 07N112W.
...OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
Please see the Special Features section for details on a Gulf of
Tehuantepec gale warning.
High pressure is the main feature controlling the wind regime
across the offshore forecast waters of Baja California. Gentle to
moderate northwest to north winds are over the offshore waters
of Baja California. Seas with these winds are 5 to 7 ft based on
altimeter data. In the Gulf of California, gentle to moderate
northwest winds are over the central and southern sections while
light and variable winds are over the northern part of the Gulf.
Seas are 3 to 5 ft with the strongest winds and 1 to 3 ft
elsewhere. Light to gentle west to northwest winds dominate the
remainder of the Mexican offshore waters with seas of 4 to 6 ft
in mixed long period northwest and southwest swell. Seas have
subsided to 4 to 6 ft over the waters surrounding the Revillagigedo
Islands. Light concentration of smoke is noted along and just
offshore the Mexican coast roughly between Manzanillo and the
Gulf of Tehuantepec due to agricultural fires.
For the forecast, high pressure over the offshore forecast waters
of Baja California will begin to weaken and shift eastward on
Thu in response to a cold front that will be approaching from the
W. Winds offshore Baja California will diminish to gentle to
moderate speeds through Thu, then will become light and gentle
winds Fri through Sat ahead of the aforementioned cold front
forecast to reach 30N120W by Sat night. In the Gulf of California,
winds will generally become light and variable on Thu throughout.
On Fri, winds over the northern part of the Gulf are forecast to
become fresh in speeds, south to southwest in direction, then
increase to fresh to strong speeds Fri night prior to the approach
of the cold front. Gentle to locally moderate winds will prevail
elsewhere with slight to moderate seas. The next gale-force gap
wind event in the Gulf of Tehuantepec region is forecast to
begin Thu morning, and will likely persist through Sat. Winds
then will diminish to fresh to strong speeds Sat night into Sun.
Seas are expected to peak to 16 or 17 ft with this upcoming
event Thu night into Fri.
...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA,
AND WITHIN 750 NM OF ECUADOR
Mainly gentle to moderate NE to E winds are noted in the Gulf of
Papagayo and downwind to about 88W. Light and variable winds and
seas of 2 to 3 ft are in the Gulf of Panama. Generally gentle to
moderate southerly winds are north of the Equator while light to
gentle southeast winds are present between Ecuador and the
Galapagos Islands. Seas are 4 to 6 ft due to a long-period south
to southwest swell.
Scattered to numerous showers with embedded thunderstorms are
still noted across the offshore forecast waters of Costa Rica,
Panama and Colombia. Winds and seas may be higher in and near
this convective activity as it is expected to stay active through
at least Thu. Hazy conditions observed along and just offshore
northern Central America are due to mostly smoke produced by
agricultural fires.
For the forecast, winds will increase in the Papagayo region to
fresh to strong speeds Thu night along with seas building to 8 to
9 ft during Fri. There is a possibility for these winds to reach
near gale-force Fri night into Sat with seas building to 8 to 11
ft. Fresh to locally strong northerly winds will develop in the
Gulf of Panama Fri night, then pulse through Sun night. Seas
with these winds will build up to 7 ft. Seas generated in the
Gulf of Tehuantepec will propagate across the outer SW offshore
waters of Guatemala and El Salvador on Fri. Abundant moisture
drawn in by a very moist and unstable southerly wind flow is
prevalent across the offshore waters of Costa Rica, Panama and
Colombia. It is expected to favor the development of scattered to
numerous showers and thunderstorms over these waters through at
least Thu.
...REMAINDER OF THE AREA...
High pressure of 1030 mb located well to the north of the forecast
region near 37N136W extends a ridge across the discussion waters
to beyond the Revillagigedo Islands. This system is the main
feature influencing the weather pattern over the waters north of
the ITCZ and west of about 110W. The pressure gradient between
the high pressure and relatively lower pressure found in the
vicinity of the ITCZ is sustaining a rather large area of fresh
to locally strong trade winds mainly from 07N to 14N west of
about 132W. Seas are 8 to 11 ft with these winds based on
altimeter data. Light to gentle N to NE winds along with moderate
seas are present elsewhere under the influence of the ridge.
For the forecast, the aforementioned high pressure will weaken on
Thu as a cold front approaches from the W. The cold front will
reach 30N140W on Fri and move across the northern forecast waters
on Sat, extending from 30N120W to 24N130W by Sat evening while
gradually weakening. Fresh to strong northwest to north winds
and a new set of northwest swell will follow the front. Seas
peaking 12 or 13 ft are currently forecast for the waters N of
29N between 128W and 136W by Sat evening.
$$
GR