AXPZ20 KNHC 010219
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0405 UTC Fri Jul 01 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
Based on 0000 UTC surface analysis and satellite imagery through
...TROPICAL WAVES AND TROPICAL LOWS..
A tropical wave is analyzed n of 07N along 79W and has been
moving w at near 20 kt. Scattered moderate isolated strong
convection is observed to the n of 03N and e of 85W to the coast
A 1008 mb low pres is analyzed along the monsoon trough at
09N104W. Although only gentle to moderate winds are observed
near the low, upper level conditions continue to support
scattered moderate isolated strong convection within 480 nm ne
and within 360 nm sw semicircles of the low. This low is
forecast to move w to near 12N104W late Fri and near 13N107W
late Sat, with favorable conditions for strengthening during
that time. The marine forecast is for strong to near gale force
winds to develop within 120 nm over the n and within 90 nm over
the s semicircles of the low as it reaches near 14N109W on Sun,
and near 12N113W on Mon. These conditions will then expand
outward to 240 nm of a low near 15N119W on Tue.
A 1010 mb low low pres is analyzed along the monsoon trough near
13N116W. Only gentle to moderate winds are observed near the low.
Scattered moderate isolated strong convection is observed within
270 nm ne and within 180 nm sw quadrants of the low. The current
environment is not favorable for rapid development. The low is
forecast to reach near 13N117W on Fri, and near 14N119W on Sat.
As the low continues west to near 16N121W on Sun the gradient
should tighten within 180 nm over the nnw semicircle supporting
fresh n-ne winds with seas building to 9 ft.
A 1011 mb low low pres is analyzed along the monsoon trough at
13N133W. Moderate southerly flow is observed within 270 nm over
the se semicircle, while moderate to fresh northerly winds are
forecast within 240 nm over the n semicircle, where scattered
moderate isolated strong convection is currently observed.
This low is expected reach near 13N136W on Fri and near 13N139W
on Sat, with the tightest gradient continuing nw of the center
as it passes 140W on Sun.
..INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
The monsoon trough extends from 10N85W to 11N97W and continues w
through an embedded low pres at 09N104W, then continues nw
through another embedded low pres at 14N114W, then w to a third
embedded low pres at 13N133W. Scatterometer winds indicate an
ITCZ develops near 12N134W and continues sw to beyond 07N140W.
Except as previously described near the tropical wave and the
surface lows, scattered moderate isolated strong convection is
observed within 240 nm either side of a line from 06N77W to
09N87W, within 180 nm either side of a line from 05.5N91W to
15N97W, and within 30 nm of the ITCZ axis.
N of 15N e of 120W:
A nnw to sse orientated trough will meander e and w over the
Baja California Peninsula and northern Gulf of California this
week supporting gentle southerly flow across the Gulf waters,
except occasionally increasing to a moderate southerly breeze
mainly across the northern gulf waters.
A ridge extends se from 23N120W to 16N101W. Moderate nw flow is
observed across the waters n of 25N, with combined seas of 5-8
ft. A weak trough will pass e across the waters n of 29.5N on
Sat, with the winds and seas diminishing and subsiding n of 25N.
Gentle anticyclonic winds surround a ridge across the waters s
of 25N, but are expected to increase to a moderate to fresh
breeze across the waters from 15-17N between 112-120W on Fri and
Sat as a surface low, previously described, passes westward
across the waters just s of 15N. Winds and seas are expected to
increase to fresh breeze across the waters from 15-17N between
104-110W on Sat night in association with another surface low
that will move wnw into the area near 15N115W on Mon, with
strong to near gale force winds shifting w across the waters
from 15-18N between 108-120W on Sun through Tue.
S of 15N e of 120W:
See Tropical Lows section.
Fresh northeasterly winds are expected across the Gulf of
Papagayo overnight and again on Fri night. Guidance is
suggesting a swath of strong e winds will develop near 11N89W on
W of 120W:
See Tropical Lows section.
A broad ridge dominates the EPAC waters to the n of 15N w of
120W. A swath of ne 7-9 ft seas, primarily due to ne swell, is
observed nw of a line from 32N120W to 20N140W. A reinforcing
surge of large n swell will reach along 32N between 118-132W
late tonight, with 8-11 ft seas forecast across the waters n of
25N between 119-135W on Sat.