000
AXPZ20 KNHC 301602
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1605 UTC Fri Sep 30 2016

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 1200 UTC surface analysis and satellite imagery through
1500 UTC.

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

The monsoon trough extends from 08.5N78W TO 07N77W TO 12N94.5W
TO 12.5N106WTO 09N123W TO LOW PRES NEAR 11.5N135W. SCATTERED
STRONG WITHIN180 NM S OF TROUGH E OF 88W. SCATTERED MODERATE TO
STRONG WITHIN330 NM N AND 360 NM S OF TROUGH BETWEEN 90W AND
110W. 

...DISCUSSION...   

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Post-tropical remnant low of Roslyn is centered near 24N117W and
is a low level clouds swirl drifting WSW. Wind have diminished to
20 kt or less and associated seas have subsided to 5 to 7 ft
surrounding this feature. The low is forecast to dissipate during
the next 12 hours. 

A weak pressure gradient over the forecast waters is supporting
mainly light to gentle winds across the area. The exception to
this is in the Gulf of Tehuantepec where gap winds reached
around 30 kt earlier this morning, and seas built to 7-10 ft.
Seas are in the 4-6 ft range north of 20N outside the Gulf of
California, 6-7 ft south of 20N, and 2 ft or less through all
but the southern entrance to the Gulf of California. High
pressure will build across the region from the NW through the
weekend and strengthen the pressure gradient W of 110W to
produce a modest increase in winds across the Pacific waters of
the Baja California Peninsula. Associated N to NW swell moving
into the area will raise seas to 6-8 ft across the northern
waters and 4-6 ft N of 20N by late Sun.

A surface trough is noted from 22N113W to low pres near
17.5N113.5W to 13N113W. Isolated to scattered moderate to strong
convection is occurring within 75 nm either side of the trough
and low. active convection will continue near and to the east of
this trough through Sat. By that time, the remnant low of
Roslynwill have dissipated, and allow the NE Pacific high
pressure to  build back across the northern waters as mentioned. 

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

Light and variable winds are expected north of the monsoon
trough, while gentle to locally moderate south to southwesterly
winds are expected south of the monsoon trough through the
upcoming weekend. Combined seas of 4 to 7 ft, primarily in long-
period southwesterly swell is expected across the offshore waters
through the upcoming weekend.

REMAINDER OF THE AREA... 

Tropical Storm Ulika has moved west of 140W and its influence on
the forecast waters will continue to decrease, with winds and
seas falling below 20 kt and 8 ft this afternoon. High pressure
will build over the northern waters which will increase the
pressure gradient, freshening winds north of the monsoon trough
this weekend. The long fetch of these fresh trades will help
build seas to the 7-9 ft range early next week. 
      
$$
Stripling