000 AXPZ20 KNHC 130910 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0910 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...SPECIAL FEATURES... Tropical Depression Henriette is centered near 21.1N 115.2W at 13/0900 UTC moving WNW at 11 kt. Estimated minimum central pressure is 1008 mb. Maximum sustained wind speed is 25 kt with gusts to 35 kt. Additional weakening is expected during the next 24 hours, and the depression is forecast to degenerate into a remnant low later today. 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 17N125W to 07N129W is producing scattered moderate convection from 12N to 16N between 122W and 130W. 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 west-northwestward around 10 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 with axis near 88W extends across Honduras and El Salvador southward into the eastern Pacific. This wave is moving westward around 15 kt. Scattered moderate convection is noted from 07N to 09N between 82W and 85W. A tropical wave with axis near 108W is moving westward around 15 kt. The latest TPW satellite imagery indicates this wave is embedded within a very moist environment. Scattered moderate and isolated strong convection is occurring from 09N to 13N between 107W and 113W. A tropical wave with an axis extending from near 17N125W to 07N129W is moving west-northwestward around 10-15 kt. Scattered moderate convection is noted from 12N to 16N between 122W and 130W. Please see the Special Features section above for more information about potential tropical cyclone development. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N76W to 10N100W to 12N105W, then resumes from 15N120W to 10N130W to 11N140W. Numerous moderate and scattered strong convection is noted from 03N to 07N east of 79W. Scattered moderate and isolated strong convection is occurring from 08N to 14N between 97W and 103W. Scattered moderate convection is noted within 90 nm of the monsoon trough between 130W and 140W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... See the Special Features section above for more information about Tropical Depression Henriette. 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 west-northwest 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 Tue through Thu 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 south or southeast of the southeastern coast of Mexico 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 easterly 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 125W. Available altimeter passes in the area show seas to at least 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 8-9 ft seas south of the equator and west of 115W per latest altimeter data. Wave heights are expected to subside below 8 ft by tonight as swell energy decays over the southern waters. $$ Reinhart