000 AXPZ20 KNHC 151552 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Thu Sep 15 2022 Tropical Weather Discussion for the eastern Pacific Ocean from 03.4S to 30N, east of 120W including the Gulf of California, and from the Equator to 30N, between 120W and 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... Southwest of Southwestern Mexico: An area of low pressure located near 15N106W or a few hundred miles southwest of Manzanillo, Mexico, continues to produce disorganized showers and thunderstorms. Environmental conditions are forecast to become more conducive for development, and a tropical depression is likely to form within the next couple of days. This disturbance is forecast to meander off the southwestern coast of Mexico through the end of this week, and then begin to move northwestward early next week. Scattered moderate to isolated strong convection is mainly on the W semicircle of the low center from 13N to 17N between 106W and 110W. Current winds are 20-25 kt with seas of 8-9 ft. The latest Tropical Weather Outlook gives this system a high chance of tropical cyclone formation through 48 hours. Near the Coast of Southern Mexico: Showers and thunderstorms associated with an area of low pressure located near 12.5N95W, off the southern coast of Mexico, are beginning to show signs of organization. Additional development of this system is expected, and a tropical depression is likely to form within the next day or so. The disturbance is forecast to move northwestward, possibly moving inland along the southern coast of Mexico this weekend. Interests in that area should monitor the progress of this system. Numerous moderate to scattered strong convection is within 180 nm W semicircle of center. Scattered moderate convection is noted elsewhere from 10N to 12N between 94W and 96W, from 11.5N to 13N between 89W and 93W, and from 14N to 16N between 93W and 96W. Current winds are 20-25 kt with seas of 8-9 ft. The latest Tropical Weather Outlook gives this system a high chance of tropical cyclone formation through 48 hours. Refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details on both areas. ...TROPICAL WAVES... The southern portion of a tropical wave with axis along 81W crosses W Panama, moving west at 5 to 10 kt. Scattered moderate convection is near the southern end of the wave axis, near the Azuero peninsula. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from northern Costa Rica near 10N84W to 1007 mb low pressure near 12.5N95W to 1007 mb low pressure near 15N106W to 1009 mb low pressure near 13N132W to 10N140W. Aside for the convection associated with the low pressure systems, scattered moderate and isolated strong convection is noted from 05N to 09N between 80W and 91W. Similar convection is from 13n to 16n between 128W and 137W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Refer to the Special Features section for details on two areas of low pressure near the outer offshore waters boundary. Gentle to moderate NW-N winds are offshore Baja California. Variable winds are across the remainder of the Mexico offshore waters, except fresh to locally strong offshore Oaxaca and Michoacan near the low pressures described above. Seas are mainly 5-7 ft in long period southerly swell across the open waters, and 1-3 ft in the Gulf of California north of the entrance. For the forecast, high pressure will build across the offshore waters of Baja California supporting moderate to fresh NW-N winds, locally strong near Punta Eugenia at night, and seas of 5-7 ft for the next few days. Gentle to occasionally moderate mainly southerly winds and 1-3 ft seas are expected in the Gulf of California. Marine conditions could deteriorate across the offshore waters between Oaxaca and Michoacan as the aforementioned low pressure systems develop, potentially then spreading west-northwest offshore southwestern Mexico. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gentle to moderate winds are noted north of the monsoon trough, while moderate fresh S-SW winds prevail south of the monsoon trough. Seas are 5-7 ft in SW swell across the offshore waters, with the exception of 6-8 ft between Ecuador and the Galapagos Islands, as well as offshore Guatemala. A moist and unstable environment interacting with the monsoon trough persists across the area north of Ecuador resulting in showers and thunderstorms. For the forecast, mainly gentle to moderate winds will persist across the offshore forecast waters, with seas of 6-8 ft in SW swell. Winds could increase to moderate to fresh between northern Costa Rica and Guatemala toward the upcoming weekend as a broad area of low pressure develops along the monsoon trough. A very moist and unstable atmospheric environment will help maintain active weather across most of the offshore waters over the next few days. REMAINDER OF THE AREA... Refer to the Special Features section for details on two areas of low pressure near the outer offshore waters boundary of Mexico. High pressure dominates the waters north of the monsoon trough and west of about 120W. The related light pressure gradient is allowing for mostly light to gentle winds over the NW corner of the forecast area. Mainly gentle to moderate winds prevail elsewhere north of the monsoon trough. Seas are 5-7 ft, mainly in long period southerly swell. Moderate to locally fresh southerly winds prevail south of the monsoon trough along with 5-8 ft seas, outside of the low pressure areas described above. For the forecast, high pressure will build across the northern forecast waters over the next few days supporting gentle to moderate winds and seas of 4-7 ft. Winds will increase some between the ridge and transient low pressure located along the monsoon trough between 130W and 140W. Marine conditions could deteriorate east of 110W as the low pressure areas over the eastern waters try to develop. Additional pulses of cross- equatorial SW swell will continue to propagate across the forecast waters east of 110W. $$ GR