000 AXPZ20 KNHC 012037 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2035 UTC Tue Sep 1 2020 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 2000 UTC. ...TROPICAL WAVES... A tropical wave axis extends southward along 79W across eastern Panama, moving westward at 10-15 kt. Scattered moderate convection is noted from 05N to 09N within 120 nm east of the wave axis. A tropical wave axis extends along 103W south of 17N, moving westward at 15 kt. Scattered moderate convection is noted from 09N to 11N within 120 nm west of the wave axis. A tropical wave axis extends along 116W south of 16N, moving westward at 10-15 kt. No significant convection is associated with the wave at this time. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 08N77W to 08N82W to 11N89W to 1012 mb low pressure near 11N104W to 1012 mb low pressure near 10N112W to 08N119W, then continues from 19N116W to 13N128W to 14N140W. Scattered moderate convection is noted within 90 nm of the monsoon trough between 123W and 129W, and within 60 nm of the monsoon trough W of 137W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A weak pressure pattern persists across the region, and recent scatterometer data shows light to gentle winds prevail across the offshore waters of Baja California and southern Mexico. A low pressure trough is analyzed along the Gulf of California, and moderate SE winds are noted across the northern Gulf. A recent altimeter pass indicates 5-6 ft seas in the waters off Colima and Michoacan. Little change in marine conditions is expected over the next several days. Moderate to locally fresh southerly flow will continue over the northern Gulf of California tonight. Gentle to moderate NW winds will prevail offshore of the Baja peninsula through the upcoming weekend. Fresh to strong northerly gap winds may pulse in the Gulf of Tehuantepec region this weekend. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Scattered showers and thunderstorms continue this afternoon near a tropical wave that extends along 79W from the western Caribbean southward across the Gulf of Panama region. Elsewhere, no significant convection is noted along the monsoon trough that extends across the offshore waters between 08N-11N. Scatterometer data indicate gentle to moderate S to SW winds persist south of the monsoon trough, with lighter winds north of the trough offshore of Guatemala and El Salvador. Seas remain 4-7 ft across much of the region, except 7-8 ft in southerly swell from near the Galapagos Islands eastward towards Ecuador. Gentle to moderate monsoonal flow will briefly freshen later this week offshore of Panama, Colombia, and Ecuador. Southerly swell will continue propagating northward, resulting in increased wave heights across the waters E of 90W through Thu night. REMAINDER OF THE AREA... A low pressure trough that extends from near 30N126W to 26N130W splits the eastern Pacific subtropical ridge this afternoon. The regional pressure gradient remains weak, and mainly light to gentle winds prevail N of 20N based on available scatterometer data. However, multiple altimeter passes indicate seas remain 7-8 ft in northerly swell over the waters N of 28N and W of 130W. Wave heights are expected to subside tonight as the swell decays over the area. Elsewhere, moderate to locally fresh southerly flow is noted south of the monsoon trough between 100W and 125W. Seas likely range from 5-7 ft, perhaps peaking around 8 ft within the fresh monsoonal flow. Farther south, altimeter data indicate 7-8 ft seas persist south of the equator, as southerly swell continues propagating northward across the region. Southerly swell will maintain 8 ft or greater seas in the waters south of the equator through the upcoming weekend. Elsewhere, a broad area of low pressure near 10N112W is producing limited shower and thunderstorm activity. The system remains disorganized, and environmental conditions are forecast to become unfavorable for any further development by Thu while the low moves slowly westward. This system has a low chance of tropical cyclone formation during the next 48 hours. Please see the latest eastern North Pacific Tropical Weather Outlook for more updates. $$ B Reinhart