AXPZ20 KNHC 261611
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1605 UTC Sun May 26 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 1200 UTC surface analysis and satellite imagery through
...Gulf of California Gale Warning...
Gale force SW gap winds have been occurring across the northern
Gulf of California north of 29.5N during the last several hours,
but have recently begun to diminish, as indicated by coastal
observations across the area. Peak winds are now assumed at 30
kt and less, and the gale warning is being allowed to expire.
Winds will diminish throughout the day and then increase to 20
to 30 kt this evening, just ahead of an approaching cold front.
As the cold front moves eastward across the northen Gulf
tonight, winds will decrease again and veer westerly, with NW
winds around 25 kt spilling into the far northern end of the
Gulf behind the front. Winds will then diminish to 20 kt or less
during the late morning hours of Mon.
...Heavy Rainfall Potential Over Central America...
A large low level cyclonic circulation that is typical for this
time of the year, called a Central American Gyre, is forecast to
persist across the far eastern tropical Pacific and Central
America for the next several days. This will continue bringing
abundant moisture and areas of heavy rainfall across portions of
Central America. Computer model forecasts have begun to indicate
the chance for increasing moisture and instability associated
with this feature Tue through Wed and could lead to a very
significant rainfall event. 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 9.5N74W to low pres near
11N88.5W 1010 MB TO 13.5N98W TO 08N115W TO 09.5N123W TO
06.5N133W. The ITCZ extends from 06.5N133W to beyond 06.5N140W.
Scattered moderate to strong convection is noted from 05.5N TO
14N between 80W AND 106W. Scattered moderate isolated strong
convection was noted from 05.5N TO 12N between 119W AND 128W.
OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
Gulf of California: Please see special features section above
for more on the gale event over the northern Gulf of California.
Over the central and southern parts of the Gulf, mainly light
and variable winds prevail, with seas 2 ft or less. Winds will
begin to shift more NW tonight through Mon as a series of weak
cold frontal boundaries approach and sweep eastward across the
northern Gulf tonight through Tuesday. Winds across central and
southern portions will increase to 10-15 kt during this time
with seas building 2-3 ft.
A weak ridge dominates the offshore forecast waters W of Baja
California producing mainly gentle to moderate NW winds off the
coast of the Baja California peninsula, and light to gentle NW
to W winds over the remainder of the open waters off the coast
of Mexico. Seas are generally in the 5-7 ft range across the
entire area in a mix of NW and cross equatorial SW swell. High
pressure well NW of the region will build over the next few
days. This will tighten the pressure gradient across the
offshore waters to support moderate to fresh NW to N winds
across the waters off Baja California tonight through Tue night,
with seas building into the 6 to 8 ft range.
Gulf of Tehuantepec: Fresh to strong northerly winds will pulse
across the Gulf of Tehuantepec region into early today, with
seas will building to 8-9 ft. Winds and seas will diminish today
and then pulse again to 20-25 kt again tonight.
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND
WITHIN 750 NM OF ECUADOR...
Please see the Special Features section for more information
about the Central American Gyre, which will continue to bring
locally heavy rains to parts of Central America and the adjacent
offshore waters through at least mid week.
Gentle to moderate SW to W winds prevail S of the monsoon
trough, with seas in the 4-7 ft range. Moderate to locally fresh
winds, and seas in the 5-6 ft range prevail N of the monsoon
trough. Low pres embedded within the broad gyre will meander
offshore the coast of Nicaragua the next couple of days. The
monsoon trough will lift northward through the early part of the
week, with southerly monsoon flow strengthening, potentially to
20-25 kt by Tue. Seas will build to 8-12 ft by mid week in this
enhanced monsoon flow.
REMAINDER OF THE AREA...
High pressure of 1025 mb centered NW of the area near 35N139W
extends a ridge SE to near the Revillagigedo Islands. The
pressure gradient between the ridge and lower pressure in the
vicinity of the ITCZ is supporting moderate to fresh NE winds
across much of the area N of the ITCZ and W of 120W. Moderate to
fresh winds will continue to prevail over this area the next
SW cross equatorial swell will dominate the forecast waters S of
10N and W of 95W for the next few days, with new swell arriving
late Tue. Seas 8 ft or greater will cover much of the forecast
waters S of 10N between 95W and 125W by early this week.