000 AXPZ20 KNHC 160855 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 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 0600 UTC surface analysis and satellite imagery through 0840 UTC. ...TROPICAL WAVES... A tropical wave extends its axis along 84/85W from 13N over Nicaragua through western 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 02N to 14N between 77W and 93W. A tropical wave is along 98W from 04N to 14N, moving west at 10 to 15 kt. Scattered moderate to isolated strong convection is noted from 04N to 16N between 93W and 105W. A tropical wave is along 116W from 05N to 15N, moving W around 5 kt. A 1009 mb low pressure center is just east of the wave axis along the monsoon trough, near 11N114W. Scattered moderate isolated strong convection is evident from 09N to 13N between 111W and 116W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N86W to 12N105W to 1009 mb low pres near 11N114W to 06N128W. The ITCZ continues from 06N128W to 07N140W. Aside from the convection associated with the tropical waves, scattered moderate convection is noted from 07N to 12N between 105W and 110W. Scattered moderate convection is also evident from 06N to 08N between 130W and 135W. ...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 southern Nevada and SE California is inducing fresh NW winds to the west of Baja California and south of 29N, as shown in the latest ASCAT satellite wind data. Seas in this area are 5 to 6 ft. The recent ASCAT pass also showed moderate to locally fresh SW winds over a small area in the northern Gulf of California, where seas are likely 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 today, 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. Gentle winds will persist elsewhere through Mon. Looking ahead, northerly winds will increase to fresh west of Baja California Mon night through the middle 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 section above for information on convection offshore Central America and Colombia. Moderate E to SE winds are likely occurring offshore Guatemala and El Salvador. Moderate NE to E winds are likely occurring in the Papagayo region. To the south of 02N, mainly gentle S to SW 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 subside this afternoon into tonight. ...REMAINDER OF THE AREA... A weak 1009 mb low pressure, mentioned in the monsoon trough section above, located near 11N114W, remains disorganized and is not producing any winds stronger than moderate speeds. This low is expected to drift WNW over the next day or so before devolving into a surface trough by Sat. A surface ridge extends from 1031 mb high pressure centered well north of the area southeastward across the subtropical waters to near 20N116W. 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 18N and west of 126W, 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 prevail 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 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 98W, described in the Tropical Waves section above. Conditions appear favorable for some development of this system thereafter as it moves W to WNW at 10 kt several hundred nm 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 tonight into Sat. N to NE swell of 8-10 ft will also affect these waters N of 25N and west of 125W through Sun. Over the remainder of the area, little change in the pattern or impacts is expected through early Mon. By late Mon through the middle of next week, NE winds are likely to increase to fresh across most of the area north of 15N and west of 115W. $$ Hagen