AXPZ20 KNHC 230900
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Sat Jun 23 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
Based on 0600 UTC surface analysis and satellite imagery through
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
The monsoon trough extends from 09N85W to a 1010 mb low pressure
near 13N104W to a 1010 mb low pressure near 12.7N115.5W to
09N121W. The ITCZ continues from 09N121W to 08N130W to 10N140W.
Scattered heavy showers and tstms within 120 nm of the coasts
from Nicaragua to Colombia. Otherwise, scattered moderate
convection is from 04N to 09N between 91W and 100W, from 08N to
18N between 99W and 110W, from 09N to 14N between 112W and 120W
and from 07N to 15N W of 130W.
OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
Moderate NW winds are forecast to continue across the waters
west of Baja California through this morning before beginning to
gradually diminish through the weekend, as a broad surface
trough shifts westward to the NE Pacific waters. Winds west of
the peninsula will become variable less than 15 kt through the
weekend. However, southerly winds will increase inside the Gulf
of California this weekend, becoming fresh to strong
southeasterly N of 28N this morning, continuing into Sun
morning. Seas in the northern Gulf of California will build to 6-
9 ft by this afternoon, then subside Sun along with a decrease
in surface winds.
Further south, long period cross-equatorial SW swell reaches the
waters off Southern Mexico with seas to 6 ft, forecast to
increase to 7 ft by this afternoon. Seas are expected to subside
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND
WITHIN 750 NM OF ECUADOR...
The monsoon trough will meander between 09N and 13N the next
several days. Light to gentle winds will prevail north of the
monsoon trough, with gentle to moderate S to SW winds expected
south of the trough axis. Long period cross-equatorial SW swell
is across southern forecast waters with seas to 8 ft. The swell
will propagate further north to the offshore waters of Costa
Rica and Colombia today and then will gradually subside through
REMAINDER OF THE AREA...
High pressure north of the area centered near 36N138W extends a
ridge SE to near the Revillagigedo Islands. Moderate to fresh
winds prevail N of 12N west of 130W with seas generally ranging
between 6 to 7 ft. Light to gentle winds dominate the remainder
of the basin.
Northerly swell will propagate into the northern waters with
seas building to 8 ft north of 29N between 123W and 127W early
Sun. Cross-equatorial southerly swell with seas to 9 ft are
south of 10N and west of 91W and will continue through Sunday
Low pressure centered near 12N115W and embedded along the
monsoon trough has an estimated pressure of 1010 mb. Model
guidance shows this low emerging from the trough and drifting
northward with a gradual increase in intensity through the
weekend. Active thunderstorms will continue in the vicinity of
this low through the weekend and early next week.
A 1010 mb low pressure is near 13.8N104.7W generating scattered
moderate convection from 09N to 18N between 98W and 110W. Global
models guidance indicate there is a high chance for this low to
develop into a tropical cyclone SW of Mexico early next week.