000 AXPZ20 KNHC 160403 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Fri Jun 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 0300 UTC. ...TROPICAL WAVES... A tropical wave extends its axis along 84W from 14N over E Nicaragua through central Costa Rica and into the east Pacific to 04N. The tropical wave is moving W at 5 to 10 kt. Scattered moderate isolated strong convection is noted from 02.5N to 14N between 80W and 92W. The strongest convection is occurring within 120 nm of the coast of Nicaragua and northern Costa Rica. A robust tropical wave is along 97W from 04N to 13N, moving west at 10 to 15 kt. Scattered moderate to isolated strong convection is noted from 04N to 13N between 95W and 107W. A tropical wave is along 116W from 05N to 15N, moving W around 10 kt. A 1007 mb low pressure center is east of the wave axis along the monsoon trough, near 10.5N112W. Scattered moderate isolated strong convection is evident from 09N to 14N between 107W and 114W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N86W to 1007 mb low pres near 10.5N112W to 07N125W. The ITCZ continues from 07N125W to 07N140W. Aside from the convection associated with the tropical waves, scattered moderate isolated strong convection is noted from 01.5N to 08N between 77W and 80W. Scattered moderate convection is also evident from 03N to 08N between 120W and 128W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A high pressure ridge extends from well NW of the area southeastward to near the Revillagigedo Islands. The gradient between the ridge and lower pressure over western Arizona and SE California is inducing fresh to locally string NW winds to the west of Baja California Sur, mainly south of Punta Eugenia. Moderate WNW to NW winds prevail west of Baja California Norte. Seas in this area are 4 to 6 ft. Fresh SW winds prevail over the northern Gulf of California, with seas 2 to 3 ft. Mainly gentle winds prevail elsewhere off Mexico with seas of 4 to 6 ft. For the forecast, a trough will deepen slightly over the lower Colorado River Valley and northern Gulf of California into Fri, while a weak ridge persists west of Los Cabos and the Revillagigedo Islands. This pattern will support fresh to locally strong NW winds west of Baja California through Sat night, with fresh SW winds over the northern Gulf of California tonight. Gentle winds will persist elsewhere through Mon. Looking ahead, northerly winds will increase to fresh west of Baja California during the early part of next week as high pressure strengthens just west of the area. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... See the tropical waves and monsoon trough sections above for information on convection offshore Central America and Colombia. Fresh winds are likely occurring in the Papagayo region as well as offshore El Salvador, partially in association with a tropical wave, described in the Tropical Waves section above. To the south of 02N, mainly gentle S winds are present, including the waters between Ecuador and the Galapagos Islands. Seas are 5 to 7 ft between Ecuador and the Galapagos Islands in S swell. Seas are generally 4-6 ft elsewhere. For the forecast, fresh winds will pulse nightly in the Papagayo region and downwind to 89W through Sat night, except for locally strong on Sat night. Moderate winds are also possible off El Salvador. Elsewhere, mainly light to gentle variable winds will prevail across the Central America offshore waters. Gentle to locally moderate S winds will continue west of Ecuador. Southerly swell of 5 to 7 ft between Ecuador and the Galapagos Islands will prevail into Fri. ...REMAINDER OF THE AREA... A 1007 mb center of low pressure, mentioned in the monsoon trough section above, located near 10.5N112W, remains disorganized and is not producing any winds stronger than moderate speeds. This low is expected to drift NW over the next couple of days before devolving into a surface trough this weekend. The chance of tropical development is decreasing, and development is unlikely. Southerly swell of up to 8 ft prevail south of 01S between 95W and 110W. A surface ridge extends from 1031 high pressure centered well north of the area southeastward across the subtropical waters to near 18N116W. The pressure gradient between the ridge and lower pressures associated with the monsoon trough/ITCZ is supporting moderate to fresh NE winds N of the ITCZ to 19N and west of 125W, where seas are 6 to 7 ft in mixed SE and N swell. To the north of 25N and west of 128W, moderate to fresh NE winds have moved in with 6 to 8 ft seas in N swell. Mainly gentle to locally moderate northerly winds are elsewhere north of the ITCZ/monsoon trough while gentle to locally moderate SE winds with seas 5 to 7 ft are south of these boundaries in southerly swell. For the forecast, an area of low pressure may form this weekend in association with the tropical wave currently analyzed along 97W, and described in the Tropical Waves section above. Conditions appear favorable for some development of this system thereafter as it moves WNW at 10 kt several hundred miles S of the southern coast of Mexico. There is a low chance of tropical cyclone formation over the next 7 days. Elsewhere, the area of fresh NE winds and building seas north of 25N and west of 130W will increase to fresh to strong for Fri night into Sat. Northerly swell of 8-10 ft will also affect these waters N of 25N and west of 125W tonight through Sun. Over the remainder of the waters, little change in the pattern or impacts is expected into early next week, except for slightly higher trade wind flow north of 08N and west of 125W. $$ Hagen