000 AXPZ20 KNHC 232140 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2145 UTC Tue Aug 23 2016 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 1800 UTC surface analysis and satellite imagery through 2100 UTC. ...SPECIAL FEATURES... Post-tropical remnant low Kay near 23.5N 121.1W at 23/2100 UTC or 617 nm west of the southern tip of the Baja California peninsula moving northwest at 9 kt. Estimated minimum central pressure is 1008 mb. Maximum sustained wind speed is 30 kt with gusts to 40 kt. No deep convection is present with the remnant low. The remnant low will continue to the northwest this evening, and then more west-northwest before dissipating tomorrow. A small area of fresh to strong winds and seas of 8 to 10 ft can be found within 150 nm in the north semicircle, however, these conditions will diminish and subside tomorrow as the low dissipates. See the final NHC forecast/advisory under AWIPS/WMO headers MIATCMEP2/WTPZ22 KNHC for more details. A tropical wave is along 104W/105W from 08N to 19N through a 1012 mb low pressure area near 14N104.5W, moving west-northwest around 10 kt. Scattered moderate convection is from 12N to 18N between 100W and 109W. An area of seas to 8 ft can be found within 150 nm in the north semicircle. Associated winds are currently 20 kt or less, however, they are forecast to increase to fresh to strong in the next few days which will build seas to 8 to 10 ft by Thursday afternoon. There is a medium chance of tropical cyclone formation during the next 48 hours. ...TROPICAL WAVES... A tropical wave is along 96W north of 10N moving west at 15 to 20 kt. Limited convection is present with this wave in the northeast Pacific, with any deep convection to the north in the southwest Gulf of Mexico. This tropical wave is forecast to merge with another tropical wave and area of low pressure to the west near 14N104.5W in the next few days. A tropical wave is along 121W from 07N to 15N moving west at around 10 to 15 kt. Associated convection is disorganized and is described in the monsoon trough section below. The tropical wave is forecast to merge with an area of low pressure currently to the east near 11.5N118W in the next few days. Fresh monsoonal flow is supporting a large area of seas of 8 to 9 ft within 480 nm in the southeast semicircle of the low. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 08N78W to 08N90W to low pressure near 11.5N118W to 10N132W. The intertropical convergence zone axis extends from 10N132W to 11N140W. Scattered moderate convection is from 08N to 10N between 120W and 124W, and also from 09N to 11N between 135W and 138W. Scattered moderate convection is also in the southern Gulf of California from 23N to 26N between 108W and 111W. This convection developed over land earlier today before propagating offshore to the southwest-west. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Ridging extends from 1022 mb high pressure near 31.5N126.5W through 28N120W to 21N110W. This ridging will change little through the upcoming weekend with mainly light to moderate northerly flow prevailing outside of the Gulf of California. In the Gulf of California, expect mainly light to moderate southerly flow, except occasionally to fresh in the northern Gulf where the pressure gradient will be slightly tighter. In the Gulf of Tehuantepec, northerly winds will continue to pulse to fresh to near gale force during the next few days due to a locally tight pressure gradient combined with nocturnal drainage flow, with the strongest winds expected during the late night into the early morning hours. Seas will build to up to 8 to 10 ft during the strongest winds. The gradient will weaken slightly this weekend allowing for northerly winds to pulse to only fresh levels. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... In the Gulf of Papagayo, the latest model guidance indicates easterly offshore winds pulsing to fresh levels during the overnight and early morning hours through early Wednesday, which will build seas to 7 ft. Otherwise, expect light to moderate winds elsewhere. Combined seas will be 4 to 6 ft through the upcoming weekend. ELSEWHERE... Other than the remnant low of Kay, and any potentially developing tropical cyclones, expect mainly moderate to locally fresh trades and combined seas of 4 to 7 ft. $$ LEWITSKY