000 AXPZ20 KNHC 210223 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 055 UTC Fri Jun 21 2019 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 0200 UTC. ...TROPICAL WAVES... A westward moving tropical wave is crossing Central America and its axis extends southward from Costa Rica along 84W to near 06N. Scattered to numerous deep convection is occurring 90 nm either side of the wave axis. A tropical wave with axis along 95W from 05N to 15N moving westward at 10-15 kt. Scattered to numerous moderate to strong convection is seen from 8N to 12N between 92W and 97W. A tropical wave with axis along 107W from 04N to 14N is moving westward near 15 kt. Only scattered showers and isolated thunderstorms are noted along this wave from 07N to 12N. A tropical wave with axis along 127W from 05N to 16N is moving westward at an estimated speed of 15-20 kt. Convection is redeveloped along and ahead of this wave where it crosses the ITCZ. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from low pressure centered in northern Colombia southwestward to 08N78W to 10N88W to 08N105W to 11N118W. The ITCZ extends from 11N118W to 08N140W. Numerous strong convection is within 120 nm north and south of the trough between 78W and 92W. Scattered moderate convection is within 120 nm south of the ITCZ between 130W and 140W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Several ship reports support scatterometer data from earlier today that gentle to moderate northwest wind is occurring across most Mexican offshore waters, as high pressure continues to dominate E of 130W. Seas are at 4-6 ft. Low pressure over the southwestern U.S. is deepening tonight, and a surface trough will extend from this low over the Gulf of California. This will cause winds to increase over the northern Gulf of California, producing strong to near gale force south to west gap winds beginning early this evening. These winds will diminish to mainly fresh speeds by early Fri afternoon before increasing again to strong speeds late on Fri night and into early Sat. Scattered to numerous showers and thunderstorms along with gusty winds are possible over the extreme southern part of Mexican offshore waters Saturday as a tropical wave passes near or south of the area. A low pressure may form at the start of next week 180 nm or more offshore the coast of southern Mexico. These may bring additional showers and thunderstorms, as well as increased winds and seas. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gentle and moderate breezes are occurring across the waters, and these winds will likely continue through the weekend. However, a ship report coupled by data from an ASCAT-C pass shows 20 to 25 winds roughly 120 nm and greater offshore Guatemala. These winds are likely occurring due to a combination of remnant gap winds from the Papagayo region and the impact of a tropical wave passing to the south. These winds should begin to diminish later tonight as the waves moves west and away from the area. Tight pressure gradient between high pressure north of the Caribbean Sea and low pressure along the monsoon trough will continue to support overnight pulses of gap wind in the Papagayo region, with speeds of 20 to 25 kt expected. A 00 UTC altimeter satellite pass showed seas of 4 to 6 feet off Central America and 5 to 7 feet across Ecuadorian offshore waters. Swell from the southern hemisphere will continue propagating northeastward offshore Ecuador, keeping slightly higher seas in place there through the weekend. REMAINDER OF THE AREA... A 1032 mb high remains quasi-stationary well north of the area near 42N139W, with a ridge extending southwestward through the Revillagigedo islands. To the south of the high pressure, northeast to east trade winds of 15 to 20 kt prevail, as supported by afternoon scatterometer data. Little change in the position of the high or the speed of the trade winds is expected through the weekend. North of 25N, seas of 8 to 10 ft are occurring due to northerly swell being generated by persistent gale force winds off the coast of California. The focus of this swell will move east and gradually shrink in size this weekend. Farther south, long-period cross-equatorial swell is causing seas of 8-9 feet south of about 07N. This swell will decay some Friday, before new swell arrives this weekend, again increasing seas south of 08N to possibly 8-10 feet. $$ KONARIK