000 AXPZ20 KNHC 112019 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Fri Sep 11 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. ...SPECIAL FEATURES... A 1007 mb low is centered along the monsoon trough near 14N107W. This low is part of a large area of disorganized weather that is being further aided by a tropical wave along 111W/112W from 04N to 19N. Active convection occurring with this area of disturbed weather consists of scattered moderate to strong convection from 11N to 15N between 108W-114W. Scattered moderate convection is within 30 nm of line from 14N108W to 18N110W and within 30 nm of line from 17N111W to 20N111W. A recent ASCAT pass continued to depict a very broad cyclonic circulation about the low and monsoon trough, with peak winds around 20 kt and seas 6-7 ft between the low and the coast of western Guerrero, and winds of 15-20 kt in the SW quadrant between 60 to 330 nm from the center, where seas are 6-8 ft. Environmental conditions appear conducive for development of this system, and a tropical depression could form over the weekend or early next week while the system moves west-northwestward away from the coast of Mexico. The system has a medium chance of developing over the next two days. For more information, see the latest Tropical Weather Outlook at https://hurricanes.gov. ...TROPICAL WAVES... A tropical wave has its axis along 86W north of 03N to across Central America. It is moving westward at about 15 kt. Earlier scattered moderate to strong convection that developed ahead of the wave during the overnight hours has shifted well to its west- southwest and south of the monsoon trough within 30 nm of line from 09N89W to 10N91W to 12N94W. A cluster of moderate convection, is to the east of the wave axis within 60 nm of 08N84W. A tropical wave has its axis along 111W/112W from 04N to 19N, moving westward at 10 kt. Convection associated with this wave is described above associated with the 1008 mb low pressure system. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from a 1008 mb low over northwestern Colombia near 11N75W to 09N84W to 14N95W to low pressure near 14N107W 1007 mb and northwestward to low pressure near 18N117W 1009 mb. It continues from this low to 14N125W and to 09N140W. Scattered moderate to isolated strong convection is between 90 and 270 nm south of the trough between 98W-103W and within 60 nm south of the trough between 81W-84W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... See Special Feature discussion of low near 14N107W. Generally tranquil marine conditions are expected across the offshore waters for the next several days as a weak pressure gradient prevails. However, the low pressure near 14N107W is expected to gradually become better organized and will likely increase winds and seas across the outer waters from offshore of Manzanillo, shifting west-northwest to the Clarion Island area. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Tranquil conditions should prevail for the next several days with light to gentle winds north of the monsoon trough along about 10N, and gentle to moderate south to southwest winds south of the monsoon trough. No significant long-period swell is expected to impact these waters during the next several days, although small swell will continue to impact the waters for the next several days. REMAINDER OF THE AREA... Low pressure of 1009 mb is centered about 120 nm southwest of the Clarion Island near 18N117W. Scattered moderate to isolated strong convection is within 150 nm of the low in the NW quadrant. A recent ASCAT pass again indicated a broad and weak cyclonic circulation consisting of gentle to moderate winds within about 210 nm of the low in the western semicircle. Some development of this system is possible during the next few days before it interacts with, and possibly becomes absorbed by the larger weather disturbance to its east discussed in the Special Feature section. High pressure of 1022 mb centered near 32N132W dominates the waters north of 20N, west of 120W. Gentle to moderate northeast trades continue north of the monsoon trough axis with seas 5-7 feet. Moderate to fresh south flow persists south of the trough with 5-7 ft seas. Long-period southwest swell is present east of 120W, contributing to combined seas of 6-8 feet near the equator. Seas will subside slightly through Tue, however wave model guidance suggests that a new set of south to southwest will be moving through waters south of the Equator and east of 120W during the early to middle part of next week. $$ Aguirre