988 AXPZ20 KNHC 132136 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1944 UTC Thu Sep 13 2018 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. ...TROPICAL WAVES... A tropical wave is along 120W from 05N to 14N moving westward at around 10 kt. Scattered moderate convection is near the northern end of the wave's axis and covers the area from 10n to 13n between 120W and 123W. This tropical wave is likely to become diffuse and difficult to track in the next 12 to 24 hours or so. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from northern Colombia near 09N75W to 11N90W to 12N100W to 09N115W to 14N130W to 12N140W. Scattered moderate to isolated strong convection from 08N to 15N between 90W and 103W. Similar convection is from 10N to 15N W of 130W. Scattered moderate N of 04N E of 82W to the coast of Colombia, including the Gulf of Panama. Clusters of moderate to isolated strong convection are noted along the monsoon trough over parts of Panama. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A trough is forecast to meander between the Gulf of California and the Baja California Peninsula through Sun. As a result, gentle to moderate winds will prevail in the Gulf of California through the remainder of the week and into the upcoming weekend. Seas will be mainly 3 ft or less, except 3 to 5 ft near the entrance of the Gulf due to long period southerly swell. A gentle to moderate NW flow will prevail across the offshore waters W of Baja California, with seas generally in the 5 to 7 ft range. Expect moderate to fresh NW winds, and seas of 6 to 8 ft N of Punta Eugenia Fri through Sun as the pressure gradient tightens with ridging building in from the NW. Additional pulses of long period southerly swell will continue to impact the entrance of the Gulf of California, and the waters W of Baja California through the upcoming weekend. A broad area of low pressure, located roughly a couple of hundred miles west-southwest of Cabo Corrientes, Mexico, is producing limited shower and thunderstorm activity. Upper-level winds are not particularly conducive for further organization, so any development of this system should be slow to occur over the next few days while the disturbance drifts west-southwestward. The latest Tropical Weather Outlook gives this system a low chance of tropical cyclone developing through 48 hours, and also through 5 days. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... The monsoon trough will meander between 08N and 10N during the next several days. Winds on both sides of the trough axis will be gentle to moderate. Winds are forecast to increase to moderate to fresh S of the axis and roughly between 100W and 115W by the end of the week into the weekend as broad low pressure along the axis deepens slightly. Additional pulses of cross-equatorial southerly swell are reaching the coasts of Mexico and Central America. Seas of 7 to 9 ft are already affecting the waters between Ecuador and the Galapagos Islands, and have also now reached to near the Azuero Peninsula. Seas will further build to 9 to 10 ft within about 90 nm SW of the Azuero Peninsula late Fri into Sat. Seas of 7 to 9 ft are expected just S of the Gulf of Panama. This swell event will start to decay late on Sun. REMAINDER OF THE AREA... The remnant low of Paul with a central pressure of 1011 mb is near 22N132W. Visible satellite imagery indicates a well defined swirl of mainly low clouds. Recent scatterometer data confirms the presence of fresh to strong winds on the NW side of the Paul along with 8 to 10 ft seas. The remnant low of Paul will move westward with the associated winds and seas gradually diminishing through 48 hours. Paul should open up into a trough by early Sat. Looking ahead, an area of low pressure is expected to develop well south of the southwestern coast of Mexico over the weekend. Thereafter, environmental conditions appear conducive for gradual development, and a tropical depression could form while the system moves generally westward to west-northwestward at 10 to 15 mph south of Mexico. Currently, this system has a medium chance of tropical cyclone formation through 5 days. $$ GR