926 
AXPZ20 KNHC 091613
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1605 UTC Mon Jun 9 2025

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.

...SPECIAL FEATURES...

Hurricane Barbara, the first hurricane of the east Pacific
hurricane season, is centered near 17.6N 106.1W at 09/1500 UTC, 
moving northwest at 9 kt. and this general motion is expected to
continue for the next couple of days. Estimated minimum central 
pressure is 991 mb. Maximum sustained wind speed is 65 kt with 
gusts to 80 kt. Some slight additional strengthening is possible 
today, but a weakening trend is forecast to begin on Tuesday.
Scattered moderate to isolated strong convection is active 
within 90 nm of the center of Barbara. Seas in excess of 12 ft 
reach as far as 135 nm to the northeast of the center, with 
maximum seas to 25 ft. Swells generated by Barbara will affect 
portions of the coast of southwestern Mexico during the next few
days. These swells are likely to cause life-threatening surf and
rip current conditions. Please consult products from your local 
weather office. Gusty winds are likely along coastal areas of 
southwestern Mexico during the next day or so.

Tropical Storm Cosme is centered near 14.5N 113.3W at 09/1500
UTC, moving west-northwest at 5 kt. A turn toward the north with
a decease in forward speed is expected tonight, followed by a 
faster north-northeast motion Tuesday through Wednesday. 
Estimated minimum central pressure is 994 mb. Maximum sustained 
wind speed is 55 kt with gusts to 65 kt. Some additional 
strengthening is forecast, and Cosme is expected to become a 
hurricane later today. Rapid weakening is expected Tuesday night 
and Wednesday. Seas in excess of 12 ft reach as far as 75 nm to
the east and 30 nm to the west of the center. 
 
Please read the latest HIGH SEAS FORECAST issued by the National
Hurricane Center at website - 
https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml and the latest 
Barbara and Cosme NHC Forecast/Advisories and Public Advisories 
at www.hurricanes.gov for more details.

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

Segments of the monsoon trough axis extends from 08N78W to 
08N85W to 12N95W, and again from 07N120W to 06N125W to 06N130W. 
The ITCZ extends from 06N130W to 07N135W to beyond 06N140W. 
Scattered moderate to isolated strong convection extends within
90 nm either side of the monsoon trough east of 100W. 

...OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Please read the Special Features section for information on
Hurricane Barbara and Tropical Tropical Storm Cosme.

Generally moderate to fresh NW winds persist across the offshore
waters of Baja California with seas of 4 to 6 ft. Gentle breezes
and moderate seas persist off southern Mexico outside of the 
area impacted by Hurricane Barbara which is mainly off Michoacan
and Colima currently. Light breezes and slight seas are noted 
over the Gulf of California.

For the forecast, adverse marine conditions will expand along the
Colima and Jalisco coastlines westward across the offshore 
waters toward Cabo Corrientes through tonight. Mariners should 
continue to monitor the latest statements from the National 
Hurricane Center, and plan their routes accordingly to avoid the 
adverse marine conditions. The remnant lows of Barbara and Cosme 
will dissipate across the Revillagigedo Islands through mid week.
Rough seas across the Revillagigedo Islands will persist into 
early Thu. Looking ahead, a broad area of low pressure is 
forecast to develop late next week south of southern Mexico. 
Environmental conditions appear conducive for some gradual 
development of this system, and a tropical depression could form 
late this week.

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

A weak pressure gradient remains over the area resulting
generally in gentle to moderate southerly winds south of the 
monsoon trough, and light to gentle winds to the north of it. 
Cross-equatorial southwest swell is producing moderate seas 
across the offshore forecast waters.

For the forecast, fresh to strong gap winds across the Gulf of 
Papagayo and the coast of Nicaragua will diminish today. Mainly 
gentle to moderate breezes will persist elsewhere. Moderate seas 
in cross equatorial swell will subside early next week. Abundant 
deep tropical moisture will persist across the region maintaining
a high chances of additional showers and thunderstorms well into
the upcoming week as a broad low pressure gyre forms west of 
Central America. 

...REMAINDER OF THE AREA....

Outside of the areas impacted by Cosme north of 10N and east of
110W, weak ridging persists north of 25N, supporting gentle to 
moderate winds west of 120W. Seas to 8 ft persist from 05N to 15N
west of 135W in a combination of moderate tradewind- induced 
waves and longer period SW swell. Moderate seas are noted 
elsewhere. 

For the forecast, little change is expected through the middle of
week outside of the area near Cosme as described in the Special 
Features section. Looking ahead, SW winds will increase into the 
monsoon trough east of 110W later in the week, with building 
seas. This pattern is associated with broad low pressure that may
develop off Central America and the far eastern Pacific. 
Environmental conditions appear conducive for some gradual 
development of this system, and a tropical depression could form 
late next week or next weekend. 

$$
GR