Tropical Weather Discussion

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Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Sat May 16 2026 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 0600 UTC surface analysis and satellite imagery through 0930 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from northwestern Colombia southwestward and westward across the southwestern Caribbean, and continues to across the central portion of Costa Rica and to 10N85W, then southwestward to 05N93W and to 07N104W, where it transitions to the ITCZ to 07N120W and to beyond 06N140W. Numerous moderate to strong convection is within 180 nm south of the ITCZ between 132W-135W, also within 120 nm south of the ITCZ between 135W-140W, and within 120 nm north of the ITCZ between 132W-137W. Scattered moderate to isolated strong convection is within 120 nm northwest of the trough between 91W-95W, and southeast of the trough from 04N to 06N between 83W-89W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... The pressure gradient between a broad area of high pressure west of Baja California and relatively lower pressure associated to the thermal trough over Baja California is generally sustaining mostly fresh northwest winds over the offshore waters of Baja California. A set of large northwest swell has recently starting to cross 30N between 117W and 125W. Seas are 8 to 12 ft north of Punta Eugenia, and 5 to 7 ft from Punta Eugenia to Cabo San Lazaro. In the Gulf of California, the gradient there is maintaining moderate west to northwest winds, except for moderate to fresh south to southwest winds in the northern portion of the Gulf. Seas are 3 to 4 ft in the Gulf as noted in an overnight altimeter satellite data pass, except for higher seas of 4 to 6 ft in long-period southwest swell at the entrance to the gulf. For the forecast, moderate to fresh south to southwest gap winds in the northern portion of the Gulf of California are expected to pulse to fresh to strong speeds tonight and Sun night, with winds reaching near gale-force Sun night. Mostly fresh northwest winds over the offshore waters of Baja California will continue through Mon morning, except increase to fresh to strong speeds west of Baja California Norte tonight into Sun due to a tightening of the pressure gradient as strong high pressure north of the area shifts eastward. Large northwest swell will induce rough to very rough seas offshore Baja California Norte through Mon night, and rough seas offshore Baja California Sur Sat through Tue. ....OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... An overnight Ascat satellite data pass indicates fresh northeast to east winds just northwest of the Gulf of Papagayo region. Seas with these winds are 4 to 6 ft. Ascat satellite data passes indicate mostly light to gentle south to southwest winds south of the monsoon trough. Seas over this part of the are 3 to 5 ft in long- period south to southwest swell per various altimeter satellite data passes. For the forecast, fresh to strong gap winds will pulse during the night time hours offshore of the Papagayo region through the period. Rough seas will accompany these winds. Moderate to fresh north to northeast winds will pulse across the Gulf of Panama tonight and Sat night. Elsewhere, gentle to moderate winds and moderate seas in southerly swell are expected through early next week. Scattered showers and isolated thunderstorms are expected over the offshore waters of Colombia, and mostly over the outer offshore waters of Panama and Costa Rica. ...REMAINDER OF THE AREA... A broad ridge stretches southeastward from a strong 1034 mb high pressure center that is located well north of the discussion area near 39N140W southeastward to near 17N113W. This feature continues to drive the general wind pattern north of the ITCZ, with moderate to fresh trades covering just about the entire area north of 08N and west of 122W. Seas over these areas are 7 to 9 ft in mixed northeast and northwest swell. Fresh northwest to north winds are over the northeast part of the area north of about 29N and east of 130W. Seas with these winds are 8 to 10 ft in northwest swell. The overnight Ascat satellite data passes show gentle to moderate east to southeast winds south of the ITCZ. Seas over these waters are 5 to 7 ft in long-perod southeast to south swell mixed with northeast swell. For the forecast, the aforementioned strong high pressure will shift slightly eastward through Mon late Sat leading to a tightening of the pressure gradient over the waters north of 27N between 120W and 130W. This will bring fresh to strong northwest to north winds for this area during the weekend. Associated long-period, large north swell is forecast to raise seas over the waters west of Baja California Norte to near 130W to the range of 11 to 17 ft Sun and Sun night, and from 9 to 14 ft from Punta Eugenia to Cabo San Lazaro. A trough, with possible weak low pressure along it, should develop offshore southern California and extreme northern Baja California early next week breaking down the described tight pressure gradient, thus allowing for the fresh to strong winds over the northeast part of the area to drop-off quite significantly. The swell will gradually decay going into the middle part of the week, with seas lowering to just below 8 ft.