107 AXPZ20 KNHC 150832 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Sat Sep 15 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 0600 UTC surface analysis and satellite imagery through 0830 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from northern Colombia near 08N75W to 12N100W to 08N126W to 08N134W. The ITCZ begins near 08N134W and continues beyond 140W. Scattered moderate isolated strong convection is N of 07N east of 91W, and from 06N to 19N between 99W and 112W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A trough is forecast to meander southwest of the Gulf of California through Sun. As a result, gentle to moderate winds will prevail in the Gulf of California continuing through Tue. 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. On Wed winds are forecast to increase to 20 kt across most of the Gulf. 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 through Sun as the pressure gradient tightens with a ridge 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 Wed. A 1007 mb low pressure is SW of the Jalisco offshore waters near 15N109W supporting seas to 8 ft in the Guerrero offshore waters. The low will slightly deepen later today, resulting in fresh winds along the coast of Guerrero and Jalisco with seas building to 9 ft. The low is forecast to move just west of the Baja California Sur offshore waters Sun, thus allowing for a decrease in the winds and seas. The low is expected to move back to the Baja California Sur offshore waters Tue along with moderate to fresh winds. There is a high chance of this system becoming a tropical cyclone within the next 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 12N during the next several days. Winds will be gentle to moderate N of the trough and moderate to fresh S of the trough as a large area of disturbed weather prevail during the next few days. Cross-equatorial southerly swell will continue to impact the coast of Central America through Wed. Seas of 8 to 10 ft are affecting the waters between Ecuador and the Galapagos Islands, and also reach to near the Azuero Peninsula. These marine conditions will persist today, and start to decay on Sun. REMAINDER OF THE AREA... A surface trough, remnant of Paul, is along 25N133W to 18N132W. Winds are 20 kt in the northern portion of the trough, however the most recent altimeter data show seas less than 8 ft in that region. The trough will continue to move westward and is forecast to move west of the area on Mon. Weak high pressure is expected to develop just north of the trough on Sun, which will slightly tighten the pressure gradient. This will result on fresh to strong winds from 21N to 24N between 135W and 139W with seas to 8 ft on Sun evening. Looking ahead, a large area of disturbed weather is centered several hundred miles south of the southern coast of Mexico. Environmental conditions appear conducive for gradual development, and a tropical depression could form by the middle of next week while the system moves generally westward to west- northwestward at around 10 kt. This system has a high chance of tropical cyclone formation within the next 5 days. Satellite imagery show a band-like of moderate convection with isolated tstms from 07N to 20N between 100W and 113W. Latest scatterometer data show fresh southwesterly winds in this area. $$ Ramos