000 AXPZ20 KNHC 160929 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Fri Aug 16 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...SPECIAL FEATURES... A large surge of moisture will continue to support heavy rainfall across Costa Rica and Nicaragua through the remainder of the week. Flash flooding and mudslides are the primary hazards with this rainfall. The focus of the heavy rain will shift northward and begin to affect parts of El Salvador, Honduras, and Guatemala later today and tonight. ...TROPICAL WAVES... A tropical wave axis near 91W extends southward across the Mexico/Guatemala border area into the eastern Pacific, moving west at 10 to 15 kt. Scattered moderate and isolated strong convection is from 06N to 12N between 82W and 92W. Numerous moderate and scattered strong convection is noted from 08N to 16N between 92W and 99W. A tropical wave axis is near 103W, moving west around 10 kt. Scattered moderate convection is noted from 09N to 12N between 99W and 102W. A tropical wave axis is near 114W, moving west at 5 to 10 kt. Scattered moderate convection is noted from 07N to 10N between 112W and 115W. A tropical wave axis is near 125W, moving west at 5 to 10 kt. Scattered moderate and isolated strong convection is noted from 11N to 15N between 119W and 121W. Scattered moderate convection is noted from 13N to 16N between 122W and 126W. A tropical wave axis extending from 04N139W to 15N137W is moving west at around 10 kt. Scattered moderate and isolated strong convection is noted from 08N to 14N between 136W to 140W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 11N86W to across the Gulf of Papagayo to 10N105W. The ITCZ continues from 10N105W to 11N114W to 08N125W to 13N136W. Scattered moderate convection is from 07N to 09N between 132W and 135W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Scattered moderate to strong convection is noted over the Gulf of California from 24N to 29N early this morning, which pushed offshore to the W from mainland Mexico. This convection should dissipate into the mid to late morning hours. A broad high pressure ridge extends across the Baja California offshore waters. Overnight and early morning scatterometer data depicted gentle to moderate NW winds in this region, and similar conditions are expected to prevail through the weekend. Some fresh winds are possible off the coast of Baja California Norte due to increased pressure gradient from low pressure over the SW US and the aforementioned high. Stronger winds off the coast of the western US will produce a set of N and NW swell that will reach the Baja California Norte waters later today through the weekend. This will build seas to 7 ft this weekend. Deepening low pressure trough along the Baja California peninsula will support fresh to strong SE winds over the northern Gulf later today through Sat, with seas building to around 6 ft. Elsewhere offshore Mexico, gentle winds will prevail through the weekend. A broad area of low pressure may from near the Gulf of Tehuantepec early next week. This could lead to strengthening N to NE flow in the region during this time. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Easterly winds have diminished to gentle to moderate in the Gulf of Papagayo region as a tropical wave moves away from the area. Downstream of the Gulf, associated wave highs of 5 to 7 feet may continue into early this morning. Fresh SW monsoon flow will cause seas to remain at 6 to 8 feet off the coasts of Panama and Costa Rica today. Broad low pressure may form offshore of Guatemala and El Salvador for the start of next week, which could lead to strengthening winds off the coast of Central America. REMAINDER OF THE AREA... Weak surface low pressure is centered near 17N135W. Fresh NE winds are located on the NW half of the low where the pressure gradient is tight, supporting seas of 7 to 9 ft. This low is forecast to continue moving west and will reach west of 140W tonight. Winds and seas will decrease in its wake. Generally moderate winds will prevail across much of the remainder of the Pacific high seas. Northerly swell will reach north of 29N this evening, causing seas of 8 to 9 ft through Sat night. $$ Lewitsky