AXPZ20 KNHC 242140
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2140 UTC Fri May 24 2019
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 1800 UTC surface analysis and satellite imagery through
...Excessive Rainfall Over Central America...
A large cyclonic gyre that is typical for this time of the year,
called a Central American Gyre, will continue bringing abundant
moisture and heavy rainfall across portions of Central America
during the next few days. Life-threatening flash flooding and
mudslides will be possible in areas of mountainous terrain.
Please refer to your local meteorological service for more
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
The monsoon trough extends from near 08.5N83W to 1008 mb low
pressure near 11.5N87W to 09N98W to 10N107W to 08N115W. The ITCZ
continues from 08N115W to 1010 mb low pressure near 09N126W to
06N130W to beyond 06N140W. Scattered moderate and isolated strong
convection is noted from 04N to 09N between 84W and 89W and
within 240 nm north of the trough between 93W and 99W. Scattered
moderate convection is occurring within 180 nm south of the
trough between 94W and 107W.
OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
A recent scatterometer pass over the Baja California Sur offshore
waters showed gentle to moderate NW flow as the pressure gradient
has relaxed today. The NW swell impacting the Baja California
waters has continued decaying, and seas are likely 8-9 ft over
the forecast waters. A high pressure ridge is expected to build
southeastward over the offshore waters Sat night and Sun, resulting
in fresh winds off the southern tip of Baja California Sur into
early next week.
Gulf of California: Scatterometer data from this afternoon showed
gentle NW flow over the central and southern Gulf of California.
A cold front is expected to approach Baja California Norte Sat
and Sat night. SW gap winds will strengthen ahead of the front
across the northern Gulf with strong to near gale force winds and
seas to 8 ft north of 29.5N Sat night and Sun. Strong SW gap winds
will persist into Sun night, then shift to NW by early Mon as the
cold front crosses the northern Gulf and weakens. Then, wind
speeds over the Gulf will diminish through mid week.
Gulf of Tehuantepec: Fresh to strong northerly winds will pulse
across the Gulf of Tehuantepec region during the overnight and
early morning hours this weekend with the assistance of the
nocturnal drainage flow. Seas will build to 8-9 ft with each
short-lived gap wind event, highest on Sun morning. Fresh winds
early on Mon will diminish to gentle speeds through mid week.
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND
WITHIN 750 NM OF ECUADOR...
Please read the Special Features section for more information
about the Central American Gyre, which will bring heavy rain to
parts of Central America and the adjacent offshore waters. As the
monsoon trough lifts northward in association with the Central
American Gyre, southerly monsoon flow will prevail over the
forecast waters and likely strengthen early next week. Seas 8 ft
or less this weekend will build to 8-11 ft early next week as SW
swell mixes with locally generated wind waves from strengthening
monsoon flow. Some gradual tropical development of a nearby low
pressure trough over the far eastern Pacific is possible while
it moves little during the next few days.
REMAINDER OF THE AREA...
Decaying NW swell over the northern forecast waters is producing
8-9 ft seas roughly north of 25N between 120W and 133W based on
earlier altimeter data and recent model guidance. This swell will
continue subsiding through tonight with seas falling below 8 ft
Recent scatterometer data highlighted fresh NE trade winds between
the ITCZ and a high pressure ridge extending southeast across
the northern waters. These trades will gradually diminish and
seas will subside this weekend as the ridge weakens north of the
A pulse of SW swell across the southern forecast waters is
producing seas to 8 ft south of the Equator between 100W and
115W. Another SW swell event will commence over the southern
waters on Sun and propagate northward through early next week.
This will result in a large area of seas 8 ft or greater south
of 10N between 90W and 125W by Tue.