000
AXPZ20 KNHC 172153
TWDEP 

TROPICAL WEATHER DISCUSSION                                  
NWS NATIONAL HURRICANE CENTER MIAMI FL                      
2205 UTC TUE MAY 17 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 1800 UTC surface analysis and satellite imagery through
2100 UTC.     
  
.Intertropical Convergence Zone/Monsoon Trough...                

The monsoon trough extends from 1009 mb low pressure over
Colombia near 09.5N75W to 09N88W to 09N103W...where it
transitions to ITCZ...continuing on to 11N118W to 09.5N129W to
09N137W to beyond 05N140W. Scattered moderate to strong
convection noted from 03.5N to 10N between 78W and 87W...and
from 07N to 12.5N between 92W and 100W. Widely scattered
moderate to strong convection noted within 240 nm N and NW of
ITCZ W of 117W.

.Discussion...                                             

A surface ridge extends from a 1032 mb subtropical high pressure
center that is centered near 36.5N140W through 23N125W to
16N107W. The pressure gradient that exists between the ridge and
lower pressure along the ITCZ/monsoon trough is supporting
mainly moderate to fresh trade winds generally south of 22N to
the ITCZ and west of 120W. Fresh to strong winds of 20-25 kt
area occurring to the N and NW of a surface trough that extends
from 05N140W TO 10N136W TO 12N133W. Wave model guidance and
recent altimeter data indicate seas across this area are running
8-10 ft in mixed SW swell and NE windwaves. The subtropical high
will migrate northwestward and merge with a new area of surface
high pressure, that is behind a cold front that is well to the
north of the area. The ridge will then shift to the west and
weaken, gradually shrinking the area of fresh tradewinds through
Wednesday afternoon as the surface trough shifts west of the
area. Widely scattered moderate to strong convection is located
within 240 nm N and NW of the trough.

Northwest to north swell propagating into northeast portions of
the area has built seas to 8 feet to the north of 29N between
118W and 126W today. This swell is originating in an area of 20-
30 kt winds that is just to the north of the forecast area off
the California coast. The winds and associated seas will shift
westward as the subtropical ridge shifts westward. Combined seas
to 9 feet are expected in the forecast waters that are to the
north of 28N to the west of 126W by the end of the forecast
period early Thursday morning.

$$ 
SS