000 AXPZ20 KNHC 301513 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1513 UTC Thu May 30 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 1200 UTC surface analysis and satellite imagery through 1500 UTC. ...SPECIAL FEATURES... ...Heavy Rainfall Potential Over Central America and Southern Mexico... A large, low-level cyclonic circulation that is typical for this time of the year, called a Central American Gyre, will persist across the far eastern tropical Pacific and Central America for the next several days. Locally heavy rainfall is likely to continue over portions of Central America and southern Mexico during the next several days. These rains could cause flash flooding and mudslides in areas of mountainous terrain. Please refer to your local meteorological service for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from Nicaragua near 12N86W to low pressure near 14N.94.5W to 09N110W to 09N125W. The ITCZ continues from 09N125W to beyond 08N140W. Numerous moderate to isolated strong convection persists from 10N to 15N between 90W and 105W. Scattered moderate convection is observed from 07N to 09N between 135W and 140W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Fresh to strong W to SW winds prevail south of the low center near 14N94.5W, with seas reaching 11 ft. A ridge extends west of the offshore waters of the Baja California peninsula. Latest surface observations indicate gentle to moderate winds with seas in the 5-7 ft range prevail elsewhere over the open waters off the coast of Mexico. Light and variable winds, with seas 2 ft or less prevail over the Gulf of California. The low pres will shift inland over Southern Mexico by tonight. The fresh to strong monsoon flow will continue S of southern Mexico through early Sat before diminishing. The high pres ridge will continue to prevail W of the Baja California peninsula through the weekend, with mainly gentle to moderate winds prevailing outside the influence of the area of low pressure mentioned above. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Please see the Special Features section for more information about the Central American Gyre, which will continue to bring locally heavy rains to parts of Central America and the adjacent offshore waters through the next several days. Low pressure off the coast of southern Mexico is producing fresh to strong SW winds over the waters south of Guatemala, with seas near 12 ft. Gentle to moderate winds, with seas in the 6-8 ft range prevail elsewhere. The enhanced SW monsoon flow will persist off the coast of Guatemala with fresh winds expected into the weekend, while seas will gradually subside as the low tracks inland over southern Mexico. Another low pressure area may form along the coast near the border of Chiapas and Guatemala by Sun, but overall pressure pattern will be fairly weak and no significant winds or seas are anticipated. Elsewhere, a set of SW swell will move into the Galapagos offshore waters Fri night and maintain 8 ft seas through the weekend and into early next week. Looking ahead, the Central American Gyre may finally break down early next week, which could allow SW winds to diminish offshore. REMAINDER OF THE AREA... High pressure prevails north of 20N. The pressure gradient between this area of high pressure, and lower pressure in the vicinity of the ITCZ, and monsoon trough, is supporting moderate to fresh winds within the tradewind belt north of the ITCZ and monsoon trough to around 20N and west of 120W. Seas over this area are in the 6-8 ft range, with components of northerly and southerly swell. Moderate to fresh trades will continue to prevail over this area for the next several days with little change in the overall pattern expected through the weekend. Long period, cross-equatorial SW swell continues to dominate much of the forecast waters south of 20N and east of 125W. Seas will gradually subside over the next couple of days as this swell decays, but another set of SW swell will move north of the equator today and tonight, with 8 to 9 ft swell reaching 05N between 110W and 120W. $$ Christensen/Konarik