AXPZ20 KNHC 161017
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Sun Jun 16 2019
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 0600 UTC surface analysis and satellite imagery through
A tropical wave with axis along 106W from 05N to 16N is moving
westward at near 15 kt. Earlier observed deep convection near
this wave has weakened to isolated showers and thunderstorms
from 08N to 15N between 100W and 107W.
A tropical wave with axis along 117W-118W from 04N to 15N is
moving westward at about 15 kt. Widely scattered moderate
isolated strong convection is occurring from 07N to 14N between
114W to 125W.
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
The monsoon trough axis extends from 09N74W TO 10N87W TO 07N95W
TO 11N120W. The ITCZ extends from 10.5N125W TO beyond 08.5N140W.
Widely scattered moderate isolated strong convection is noted
from 02N to 08N east of 81W, and from 07N to 14N between 114.5W
OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
The pressure gradient between a high pressure ridge west of Baja
California and a low pressure trough along the Baja California
peninsula is maintaining moderate northwest to north winds
across most of the adjacent offshore waters where seas remain in
the 4-5 ft range. Winds and seas off Baja California will change
little through early on Mon as the ridge remains over offshore
waters. However, winds will increase to fresh speeds near the
coast during the evening hours through Sun night mainly in the
region between Punta Eugenia and Cabo San Lazaro. Low pressure
is expected to cover a rather expansive area over the
southwestern United States and along California by late Mon
afternoon in response to a sharpening mid/upper-level trough
that will pass over those regions. This will result in a
weakening of the ridge allowing for wind to briefly diminish
through middle part of the upcoming week.
Mainly gentle southwest to south winds were captured by an
overnight ASCAT pass over the southern half of the Gulf of
California. These winds will continue on Sun. By late Sun night,
gentle to moderate southeast to south winds will be over the
entire Gulf and through Mon. These winds then become light and
variable on Tue and through Wed evening. Winds will increase to
fresh speeds over the far northern part of the Gulf Mon night
before diminishing to moderate speeds early on Tue. Long-period
southwest swell is reaching the Mexican offshore waters,
however, with most of the energy spent already, the seas will
remain in the 5-6 ft ft range through the middle of the upcoming
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND
WITHIN 750 NM OF ECUADOR...
Fresh to strong nocturnal offshore winds will continue pulsing
across the Gulf of Papagayo region through the middle part of
the upcoming week, with seas peaking around 7-8 ft downstream of
the Gulf. Otherwise, fairly tranquil conditions will persist off
Central America under a weak pressure pattern. Gentle to
moderate south to southwest flow with scattered showers and
thunderstorms will prevail south of the monsoon trough through
Sun night and early into next next week.
Long-period southwest swell propagating through the southern
waters will build the waveheights to 8 ft between Ecuador and
the Galapagos Islands through the remainder of this weekend.
Wave model guidance suggests that another set of south to
southwest swell will propagate through the southern waters west
of 85W Tue night through Thu building waveheights there to
a peak of 8 ft again before they begin to subside late on Thu.
REMAINDER OF THE AREA...
A high pressure ridge prevails across the northern waters.
Moderate to fresh northeast winds are between the ridge and the
ITCZ west of 125W. Seas in this region are generally 5-7 ft
based on the latest altimeter data. Moderate to locally fresh
trades are expected to persist mainly south of 20N through the
remainder of this weekend and into early next week as a couple
of tropical waves moves south of the ridge.
Long period southwest swell will continue to propagate through
high seas areas east of 120W through Sun night. Seas will remain
8 ft or greater south of the Equator through the middle of the
upcoming week, as a reinforcing set of southwest swell is
expected to reach the far southwestern waters by Mon night.
Expect 8-9 ft seas south of the Equator and west of 100W by Tue.
Elsewhere, northwest to north swell will impact the far northern
waters west of about 125W beginning on Mon night and continuing
through Wed night as strong high pressure builds southward to
the north of the area and while low pressure lingers offshore
California. Waveheights associated with the swell will likely
build to 8-10 ft north of 28N.