Tropical Weather Discussion
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AXPZ20 KNHC 250229

0405 UTC WED MAY 25 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 0000 UTC surface analysis and satellite imagery through
0215 UTC.


A tropical wave was analyzed to the n of 06N along 78.5W, and
has been moving w at 15-20 kt. Currently scattered moderate
isolated strong convection is noted from 04-10N to the e of 87W
including over and along the coasts of Colombia and Panama.


The monsoon trough was analyzed from 10N85W to 08N93W to 11N116W
to an embedded 1012 mb surface low pres at 10N124W with the
monsoon trough continuing sw to 07N137W where scatterometer
winds indicate an ITCZ forms and continues sw to beyond 07N140W.

Scattered moderate isolated strong convection is observed within
120 nm of lines from 08N94W to 07N99W,and from 06N105W to
12N115W. Similar convection is noted within 180 nm of line from
10N119W to 06N140W.

The surface low is forecast to move nw to near 12N125W on Thu
and then dissipate on Thu night. The gradient is supporting
fresh to strong ne winds over the w semicircle of the low.


N of 15N e of 120W:

A NNW-SSE surface trough is currently analyzed over the Gulf of
California. The trough will meander e and w over the next few
days. Moderate southwesterly winds are expected to develop
briefly early tonight across the gulf waters from 29.5-31N and e
of the trough. Strong to near conditions will develop again on
Wed afternoon from 29-31N, while NW-N 20-25 kt condtions are
expected n of 31N and will persist into late Wed night.

A surface ridge extends from 24N120W to 19N107W. The ridge is
expected to shift slightly sw on Wed. Moderate NW-N winds
currently across the open Pacific are expected to increase to a
fresh breeze tonight across the waters n of 28N within 120 nm of
the Baja Peninsula. The winds will briefly diminish to 20 kt or
less early Wed, then develop again late Wed. The gradient will
continue to tighten on Thu with strong to near gale winds from
28-32N e of 118W late Thu. The gradient should begin to relax
on Fri.

Strong nw to n winds are forecast from 19-24N e of 111W late
Wed, and will spread w across the waters from 18-21N between 105-
108W late Thu.

Combined seas of 3-6 ft are currently observed between 110-120W.
Little change expected until the winds increase n of the ridge
with seas then expected to build to near 8 ft in the area of
strong winds. Combined seas of 4-7 ft are expected across the
remainder of the open Pacific waters n of 15N e of 110w,
partially due to long-period cross equatorial swell.

S of 15N e of 110W:

Moderate ne drainage flow expected across the Gulf of Papagayo
tonight, then mostly light drainage flow is expected the rest of
the week. Light drainage flow is expected this week across the
Gulf of Panama.

Otherwise, gentle northerly flow expected n of the monsoon trough
with combined seas of 4-7 ft in mixing cross-equatorial southerly
swell and long-period nw swell. Light to moderate southerly flow
currently across the waters s of the monsoon trough is expected
to increase to a fresh breeze on Thu with seas building from 4-7
ft to 5-8 ft.

Elsewhere from the equator to 32N e of 140W:

A surface ridge extends from 32N140W to beyond 24N120W. Moderate
to fresh anticyclonic flow is expected n of the ridge till Thu
night when the gradient will support strong nw-n winds along
32N. These conditions will spread s to along 30N between 122-
130W on Fri night accompanied by 8-11 ft seas.

Fresh to locally strong ne trades expected across the tropics n
of the monsoon trough and ITCZ this week with combined seas of 5-
8 ft.

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