000 AXPZ20 KNHC 080356 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0355 UTC Sun Jul 8 2018 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 meteorological analysis. Based on 0000 UTC surface analysis and satellite imagery through 0300 UTC. ...TROPICAL WAVES... A tropical wave has an axis along 98W N of 08N, moving westward at 10 to 15 kt. Scattered moderate and isolated strong convection are from 06N to 13N between 95W and 101W. A tropical wave has an axis along 104W from 07N to 19N, moving westward at around 10 kt. Isolated thunderstorms are within 90 nm of the wave axis. A tropical wave has an axis along 118W from 05N to 16N, moving westward at 10 to 15 kt. Numerous moderate and isolated strong convection are from 06N to 11N between 115W and 125W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N83W to 08N96W. The ITCZ begins near 07N105W and extends to 07N116W, then resumes near 08N120W to 08N130W to beyond 08N140W. Aside from convection associated with the tropical waves, scattered moderate and isolated strong convection are within 240 nm N and 180 nm S of the ITCZ axis between 125W and 140W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A weak ridge axis extends from high pressure NW of the region to near the Revillagigedo Islands. A surface trough extends across Baja California, while another surface trough is just west of Baja California extending from 30N118W to 26N119W. Due to the presence of these troughs, and the lack of strength of the surface ridge, a weak pressure pattern is in place N of 15N across the offshore waters promoting mainly gentle winds. The trough W of Baja California is expected to drift westward the next few days, which will help maintain the weak flow over the region. Meanwhile, NW swell generated by strong winds offshore California will continue to propagate offshore Baja California Norte through Sun, generating seas of 6 to 8 ft. Gulf of Tehuantepec: High pressure north of the region along with nocturnal enhancements will support strong northerly winds with seas up to 9 ft each night through Sun night. The high will strengthen Mon night through Thu which will help increase the nocturnal winds to near gale force. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Fresh to strong nocturnal winds will continue downstream of the Gulf of Papagayo the next several nights, with seas to 8 ft. Gentle to moderate easterly winds are forecast elsewhere north of the monsoon trough, which will meander between 06N and 09N. Gentle to moderate southerly winds are expected south of the trough axis. Long period cross-equatorial swell greater than 8 ft currently across the offshore waters of Ecuador and Colombia will linger across these locations through Mon before diminishing below 8 ft by Mon night. REMAINDER OF THE AREA... The post-tropical remnant low of Fabio is centered near 25N135W, moving WNW. Scattered showers continue N of the center to beyond 30N between 132W and 137W. An 1802 UTC scatterometer pass indicated that winds of 20 to 30 kt continue within about 210 nm of the northern semicircle of the low. These winds are being produced by the pressure gradient between the weakening low, and high pressure to the north of the region. Seas to 12 ft continue under the stronger winds, as confirmed by a 1700 UTC altimeter pass, with a larger area of swell 8 ft or greater covering the waters W of a line from 30N132W to 24N132W to 10N138W. The stronger winds will decrease in areal coverage and intensity through Sun as the low continues to weaken and degenerates into a trough of low pressure. The associated area of swell will also continue to shrink in size, with seas diminishing below 8 ft over this region by Mon morning. Strong NW winds north of the area along the California coast will cause 8 to 9 ft seas in northerly swell to reach the waters N of 28N between 120W and 126W from now through most of Mon, before retreating to along and N of 30N through midweek. Cross equatorial swell combined with wind waves from the Gulf of Papagayo will generate seas to 9 ft S of 12N and E of about 102W Sun and Mon. $$ Latto