000 AXPZ20 KNHC 131551 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1402 UTC Tue Aug 13 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... Post-Tropical Cyclone Henriette near 21.4N 116.1W 1008 mb at 13/1500 UTC moving WNW at 10 kt. Maximum sustained winds 25 kt gusts 35 kt. Henriette will become a remnant low and move to 21.8N 117.8W this evening, 22.0N 120.0W Wed morning, and dissipate Wed evening. This system is devoid of any significant convection. See latest NHC forecast/advisory under AWIPS/WMO headers MIATCMEP4/WTPZ24 KNHC for more details. An elongated trough of low pressure associated with a tropical wave extending from near 06N129W to 17N127W is producing scattered moderate convection within 120 nm either side of a line from 16N123W to 08N133W. Environmental conditions are forecast to be conducive for gradual development during the next few days, and a tropical depression is likely to form later this week while the system moves WNW at 10 to 15 kt. This system has a medium chance of tropical cyclone formation during the next 48 hours. Please see the latest eastern North Pacific Tropical Weather Outlook for more information. ...TROPICAL WAVES... A tropical wave has an axis extending N from the Gulf of Panama near 08N79W over the Caribbean to near 22N89W. This wave is moving westward at 20 to 25 kt. Scattered moderate and isolated strong convection is noted N of a line from 03N77W to 06N86W. A tropical wave has an axis extending N from 04N89W over Central America to 22N89W. This wave is moving westward around 15 kt. Scattered moderate and isolated strong convection is seen from 06N to 09N between 90W and 94W. A tropical wave with an axis extending from 04N109W to 16N109W is moving westward at 10 to 15 kt. The latest TPW satellite imagery indicates this wave is embedded within a very moist environment. Numerous moderate and scattered strong convection is found from 11N to 13N between 107W and 113W. Scattered moderate and isolated strong convection is occurring elsewhere from 10N to 13N between 107W and 115W. A tropical wave with an axis extending from near 06N129W to 17N127W is moving W around 10 kt. Scattered moderate convection is observed within 120 nm either side of a line from 16N123W to 08N133W. Please see the Special Features section above for more information concerning potential tropical cyclone development of this system. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N75W to 09N93W to 12N105W, then resumes from 17N119W to 11N134W to beyond 11N140W. Scattered moderate and isolated strong convection is present from 08N to 15N between 97W and 106W. Scattered moderate convection is seen from 08N to 11N between 135W and 140W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... See the Special Features section above for more information about Tropical Depression Henriette. Showers and thunderstorms have pushed SE from Mexico over the coastal waters between Acapulco and Cabo Corrientes. This area of weather will produce some gusty winds and enhanced seas before it dissipates later this afternoon. Gentle to moderate NW flow persists over the Baja California offshore waters. Recent scatterometer data also shows moderate W to NW winds along the Mexican coast between Cabo Corrientes and Acapulco. Little change is expected in the overall pattern this week as high pressure remains centered WNW of the region. Locally fresh winds may develop near Punta Eugenia and Cabo San Lazaro by mid week as a low pressure trough strengthens near Baja California. This feature will also support fresh SE to S winds over the northern Gulf of California Fri and Sat. Elsewhere, fresh northerly winds will pulse across the Gulf of Tehuantepec tonight and Wed night as weak high pressure over the central Gulf of Mexico maintains a modest pressure gradient across southern Mexico. Looking ahead, a broad area of low pressure is forecast to form SE of the coast of the Mexican State of Chiapas late this week. Environmental conditions are expected to be conducive for gradual development of the system over the weekend. This system has a low chance of tropical cyclone formation during the next five days. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Overnight scatterometer data showed moderate to fresh NE to E winds across the Gulf of Papagayo region. The pressure gradient across the western Caribbean Sea and Central America will continue to support fresh to occasionally strong NE to E winds pulsing across the Gulf of Papagayo through Wed night. Wave heights will peak around 7 ft each morning downstream of the Gulf. Recent altimeter passes indicate seas have subsided below 8 ft near the Galapagos Islands as southerly swell has decayed over the southern waters. Freshening SW monsoon flow Wed through Thu will build seas to 8 ft off the coast of Central America. REMAINDER OF THE AREA... Please see the Special Features section for more information about potential tropical cyclone development associated with an elongated area of low pressure presently near 125W. A large region of moderate to fresh trade winds is noted in scatterometer data from 12N to 24N west of 120W. Altimeter passes in the area this morning show seas to around 8 ft within the stronger trades. Little change is expected over the next couple days as a modest pressure gradient persists between the monsoon trough and high pressure centered north of the region. Mixed SE and SW swell is maintaining 8 ft seas south of 03S and west of 109W per latest altimeter data. Wave heights in this area are expected to subside below 8 ft by tonight as swell energy in these waters decays. $$ CAM