000
AXPZ20 KNHC 160312
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0405 UTC Sun Jul 16 2023

Tropical Weather Discussion for the eastern Pacific Ocean from
03.4S to 30N, east of 120W including the Gulf of California, and
from the Equator to 30N, between 120W and 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
0230 UTC.

...SPECIAL FEATURES...

Hurricane Calvin is centered near 15.4N 132.0W at 16/0300 UTC
moving WNW at 15 kt. Estimated minimum central pressure is 975
mb. Maximum sustained wind speed is 85 kt with gusts to 105 kt.
Numerous moderate to strong convection is noted within 140 nm of
center. Seas in excess of 12 ft seas extend within 180 nm N 
semicircle and 120 nm S semicircle with maximum seas estimated to
reach 33 ft. On the forecast track, the center of Calvin is 
expected to move into the central Pacific on Monday morning while
weakening. Swells generated by Calvin are expected to begin 
reaching the Hawaiian Islands early next week. These swells are 
likely to cause life-threatening surf and rip current conditions.
Please consult products from your local weather office for
details.

Please read the latest HIGH SEAS FORECAST issued by National 
Hurricane Center at web-site 
https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml and the latest 
Hurricane Calvin Forecast/Advisory and Public Advisory at 
www.hurricanes.gov for more details. 

...TROPICAL WAVE...

A tropical wave is along 87W and N of 04N, moving W at 10 to 15 
kt. The wave extends northward over central America and the NW 
Caribbean. Scattered moderate convection is noted along the
northern half of the wave mainly N of 12N.

A second tropical wave is along 108W from 03N to 18N, moving W 
at 10 to 15 kt. Scattered moderate convection prevails from 08N
to 14N between 106W to 114W. 

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

The monsoon trough extends from 10N86W to 07N121W. The ITCZ 
stretches from 07N121W to 09N124W, then resumes near 09N136W to
beyond 07N140W. Scattered moderate convection prevails from 02N
to 13N between 90W and 120W. 

...OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

A surface ridge dominates the offshore forecast waters of Baja 
California and extends SE beyond the Revillagigedo Islands. 
Gentle to moderate NW winds prevail with seas of 4 to 6 ft. Light
to gentle southerly winds are over the Gulf of California where 
seas are in the 1 to 3 ft range with the exception of 3 to 4 ft 
near the entrance to the Gulf. Moderate to fresh northerly winds 
prevail in the Tehuantepec region with seas of 4 to 6 ft. 
Elsewhere across the remainder of the Mexican offshore waters, 
light to gentle winds and seas of 4 to 5 ft in SW swell are 
noted.

For the forecast, the ridge will continue to dominate the offshore
forecast waters of Baja California through at least Tue generating
gentle to moderate NW winds with seas in the 4 to 5 ft range. 
Similar wind speeds are expected in the Gulf of California with 
seas of 3 ft or less. By Wed, winds and seas will increase some 
over the Gulf of California. At that time, moderate to fresh
southerly winds and seas of 3 to 5 ft are expected with the
highest seas over the northern part of the Gulf. Fresh to strong
northerly winds are forecast in the Tehuantepec region Mon through
Tue with seas building to 8 ft.  

...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, 
AND WITHIN 750 NM OF ECUADOR...

Satellite derived wind data provide observations of fresh to 
strong NE to E winds across the Papagayo region and downwind to
about 89W. Seas are 5 to 7 ft within these winds. Light to gentle
winds and seas of 4 to 5 ft are noted over the remainder of the 
offshore waters north of 03N. Gentle to moderate southerly winds
are observed south of 03N where seas are 4 to 6 ft.

For the forecast, fresh to strong NE to E winds are forecast in 
the Papagayo region through the middle of the week with seas of 
5 to 7 ft. Light to gentle winds will dominate the remainder of 
the offshore forecast waters, with the exception of gentle to 
moderate southerly winds between Ecuador and the Galapagos 
Islands, and moderate to locally fresh NE to E winds across the 
offshore waters of Guatemala and El Salvador. Outside of the 
Papagayo region, seas of 4 to 5 ft in SW swell are expected.
However, seas generating in the Papagayo area will spread across
the offshore waters of Guatemala and El Salvador building seas 
to 5 to 7 ft.

...REMAINDER OF THE AREA...

Please see the SPECIAL FEATURES section above for more information
on Hurricane Calvin.

Aside from Calvin, a ridge prevails across the north waters anchored
by a 1025 mb high pressure center located N of the area near 
36N136W. Gentle to moderate winds are noted under the influence 
of the ridge. Wind and seas could be higher near the convective 
activity along the ITCZ/Monsoon Trough.

For the forecast, Hurricane Calvin will move to 16.0N 134.3W 
Sun morning, 16.6N 137.6W Sun evening, weaken to a tropical storm
near 17.1N 140.9W Mon morning, 17.4N 144.4W Mon evening, 17.9N 
148.0W Tue morning, and 18.4N 151.6W Tue evening. Calvin will 
change little in intensity as it moves to 19.5N 158.5W late Wed.
Seas in excess of 8 ft generating by Calvin, will continue to 
propagate across the open waters, covering the area from 11N to 
23N between 125W and 140W by Sun afternoon. An area of fresh to 
strong E winds, with seas to 8 ft is forecast to develop to the S
and SW of the Tehunatepec region by Sun night into Mon morning 
and could be associated with a developing low pressure along the 
monsoon trough.

$$
ERA