000
AXPZ20 KNHC 170259
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
259 UTC Thu May 17 2018

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
meteorological analysis.

Based on 0000 UTC surface analysis and satellite imagery through
0530 UTC. 
  
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 

The monsoon trough axis reaches from 08N78W to 10N100W to 1011 mb
low pressure near 12N117W to 06N130W. The intertropical convergence
zone continues from 06N130W to beyond 02N140W. Scattered moderate
convection is noted from 05N to 10N between 90W and 100W, and
from 07N to 11N between 115W and 120W.

...DISCUSSION...

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Off Baja California, recent ship observations indicate fresh 
northerly winds, between 1022 mb high pressure centered west of 
the area and lower pressure over northwest Mexico. Concurrent 
altimeter satellite data showed seas roughly 5 to 6 ft. A weak 
trough will move across the waters off Baja California and the 
Gulf of California late Thu through Fri. The fresh northerly 
winds will pulse to 25 kt off Baja California Norte early Thu, 
then between Punta Eugenia and Cabo San Lazaro Thu night through 
Fri. Seas will reach 8 ft with the strong winds and a component 
of long period SW swell. Looking ahead, fresh NW flow will 
persist through the remainder of the period.

For the Gulf of California, moderate NW flow with 2 to 4 ft seas
will persist through Thu. Fresh to strong westerly gap winds will
pulse over the northern Gulf of California Thu night in the wake
of a weak trough moving across the region. Little change is 
anticipated through the remainder of the period.

Farther south along the remainder of the coast of Mexico, weak 
northerly flow is noted. Seas are 5 to 7 ft with a component of 
SW swell. Showers and thunderstorm are active well to the south
of the Gulf of Tehuantepec beyond 250 nm along the monsoon trough.
This activity will persist on and off through early next week 
and may drift northward as the monsoon trough breaks with
moderate SW flow.
  
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND 
WITHIN 750 NM OF ECUADOR... 

Gulf of Papagayo: Light to gentle winds will dominate the gulf 
the entire forecast period as weak pressure will prevail across 
Central America. Seas of 4-7 ft are forecast over the Gulf and 
nearby waters through Tue.

Gulf of Panama: Gentle to moderate S to SW winds are forecast 
through Tue with seas of 4-6 ft in long period SW swell, 
building to 5-7 ft on Mon as the swell reaches the coasts of 
Panama and Colombia. Expect increasing wave action along those 
coasts.

Elsewhere, gentle to moderate SW winds are expected to the south 
of the monsoon trough with light to gentle variable winds north 
of trough as a weak pressure pattern remains over Central 
America. Seas are forecast to build to 6-7 ft in long period SW 
swell between Ecuador and the Galapagos Islands tonight and 
continuing through the weekend. Wave mode guidance indicates 
that these seas will build to 8 ft on Mon and will subside Tue.

REMAINDER OF THE AREA...

A 1022 mb high is centered near 28N126W, with a ridge axis 
extending southeastward to near the Revillagigedo Islands.
Farther south, 1011 mb low pressure is centered along the monsoon
trough near 12N117W. Scattered moderate showers and thunderstorms
are noted in convergent SW flow south of the monsoon trough from 
07N to 11N between 115W and 120W. Gentle to moderate northerly 
breezes are noted north of 20N within the ridge, and moderate to 
fresh trade winds farther south to the monsoon trough. An 
altimeter satellite pass from 23 UTC indicated seas were reaching
7 to 9 ft in the area of fresh trades, assisted by longer period
SW swell. Farther south, additional altimeter passes showed seas
7 to 8 ft in a new group of SW swell reaching the equator. 

$$
Christensen