AXPZ20 KNHC 262031
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2030 UTC Tue May 26 2020
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 1800 UTC surface analysis and satellite imagery through
The axis of a tropical wave is analyzed along 100W north of 05N,
moving west around 15 kt. Numerous moderate scattered strong
convection is noted from 07N to 11N between 95W and 100W.
The axis of a tropical wave is analyzed along 84W north of 06N,
moving west around 10 kt. Scattered moderate convection is noted
inland over portions of Nicaragua and Costa Rica.
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
The monsoon trough axis extends from 07N77W to 05N84W to 12N96W
to 1010 mb low pressure near 10N105W to 09N132W. The ITCZ extends
from 09N132W to 08N140W. Numerous moderate scattered strong
convection is noted within 180 nm of the monsoon trough between
85W and 95W. Elsewhere, scattered moderate convection is
occurring within 180 nm of the monsoon trough east of 85W, and
within 120 nm SE semicircle of the low.
OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
Light to gentle NW winds prevail over the Baja California
offshore waters between a weakening offshore high pressure ridge
and low pressure over inland Mexico. Light to gentle SE winds are
noted over the Gulf of California. Farther south, recent
scatterometer data shows gentle to moderate N winds offshore of
southern Mexico, north of the monsoon trough. Seas generally
remain 4-6 ft across much of the forecast area, with 6-7 ft seas
in SW swell south of the Tehuantepec region.
Little change in marine conditions is expected over the next
couple days as offshore high pressure weakens. Long-period SW
swell will continue propagating across the offshore waters
through the weekend. A broad area of low pressure is expected to
form in a few days offshore of southern Mexico, Guatemala, and
El Salvador. Environmental conditions appear conducive for
gradual development of this system, and a tropical depression is
likely to form late this week or over the weekend.
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL
AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR...
Satellite imagery and GOES-16 lightning data show the monsoon
trough remains active this afternoon, with the strongest showers
and thunderstorms located offshore of Nicaragua, Costa Rica, and
Panama. Recent scatterometer data shows generally moderate to
locally fresh S to SW winds south of the monsoon trough, with
light and variable winds north of the monsoon trough. Seas are
generally 4-7 ft across the region in SW swell.
Gentle to moderate monsoon flow will strengthen later this week
as broad low pressure is expected to form offshore of southern
Mexico, Guatemala, and El Salvador. Environmental conditions
appear conducive for gradual development, and a tropical
depression is likely to form late this week or over the weekend.
Expect increasing winds and seas, along with gusty showers and
thunderstorms, over the offshore waters late this week and into
the weekend. Long-period SW swell will continue propagating
across the region for the next several days.
REMAINDER OF THE AREA...
An upper-level low pressure system centered near 26N131W has
induced a surface trough over the northern waters, per recent
scatterometer data. Moderate to fresh winds are noted with this
feature over the waters N of 28N W of 130W. Gentle to moderate
trades continue W of 125W between a weak high pressure ridge and
the ITCZ/monsoon trough. A broad area of fresh winds is located S
and SE of low pressure analyzed along the monsoon trough near
10N105W. Seas in this region are 8-10 ft in combined wind waves
and SW swell. Elsewhere, seas 8 ft or greater are noted south of
the Equator W of 100W.
A trough or weak surface low will remain nearly stationary near
26N131W for the next couple days, with fresh winds and seas to 8
ft over the far NW portion. The low pressure along the monsoon
trough will drift NE over the next day or so, then become
absorbed into a broader cyclonic circulation later this week
over the eastern Pacific.