000
AXPZ20 KNHC 251534
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1605 UTC Tue May 25 2021

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 1200 UTC surface analysis and satellite imagery through
1500 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

The monsoon trough extends from a 1010 mb low near 10N77W to
09N84W to 13N101W. A surface trough extends from 14N109W to
06N113W. The ITCZ extends from 09N118W to beyond 08N140W. 
Scattered moderate convection is noted within 100 nm on either
sides of the monsoon trough and ITCZ, as well within the surface
trough. 

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

A surface ridge extends from 1027 mb high pressure centered west
of the area near 34N138W southeastward toward Socorro Island. 
Latest observations indicated this pattern is supporting gentle 
to moderate NW winds off Baja California with 4 to 6 ft seas in a
mix of SW and NW swell. Light breezes and slight seas are noted 
in the Gulf of California. Light breezes prevail elsewhere 
across the offshore waters of southern Mexico. Seas are 5 to 6 ft
in SW swell off southern Mexico. Smoke from forest fires and 
agricultural burning may be limiting visibility in the nearshore 
waters from Guerrero to Nayarit. 

For the forecast, the high pressure west of the region will 
maintain moderate NW winds off Baja California into Wed. Winds 
over this area will increase modestly at the end of the week. 
Moderate to fresh northerly winds will pulse in the Gulf of 
Tehuantepec through mid week, then possibly increase to strong 
pulses on Wed night. Gentle to moderate winds will prevail 
elsewhere through the week. Looking ahead, low pressure may form 
beyond 250 nm off southern Mexico by Fri or Sat, possibly 
allowing associated fresh swell to enter into the offshore zones 
of southern Mexico. 

OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and 
WITHIN 750 NM OF ECUADOR...

Fresh winds are noted over and downwind of the Gulf of Papagayo,
with light to gentle winds prevailing elsewhere north of the 
monsoon trough. Gentle to moderate S winds prevail south of the 
monsoon trough. Seas are in the 5 to 7 ft range in S to SW swell.
Showers and a few thunderstorms remain active north the monsoon 
trough beyond 120 nm of the coast from northern Costa Rica to
Guatemala.

For the forecast, fresh to locally strong E winds are expected 
to pulse in the Gulf of Papagayo into Thu. Gentle to moderate 
winds are expected to continue elsewhere into Fri night. Looking 
ahead, low pressure may form beyond 250 nm off northern Central 
America by Fri or Sat, possibly allowing associated fresh swell 
to enter into the offshore zones of from Nicaragua to Guatemala. 

REMAINDER OF THE AREA...

The subtropical ridge continues to dominate the waters north of 
15N, anchored by 1027 mb high pressure centered near 34N138W.  
The pressure gradient between this area of high pressure and 
lower pressure in the vicinity of the ITCZ is supporting moderate
to locally fresh winds north of the ITCZ and monsoon trough and 
west of 120W. Seas are 5 to 7 ft across much of the open Pacific
west of 115W. S to SW swell prevails east of 120W and south of 
15N, where seas are in the 4 to 6 ft range. A very broad upper 
trough is over the tropical waters between 105W and 115W, 
supporting clusters of scattered showers and thunderstorms along 
the monsoon trough east of 115W.

For the forecast, expect moderate to fresh NW winds and NW swell
up to 7 ft north of 25N and east of 125W by mid week as high 
pressure builds in the wake of a weak trough moving across the 
region. High pressure will support fresh trade winds to the north
of the ITCZ and west of 120W. Seas in the 5 to 7 ft range over 
much of this area will gradually subside through the mid week. 
Looking ahead, an area of low pressure may form along the monsoon
trough east of 110W but beyond 250 nm off northern Central 
America and southern Mexico by Fri into Sat, then slowly drift to
the WNW parallel to the coastline.

$$
ERA