000 AXPZ20 KNHC 120252 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Fri Jul 12 2019 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 0000 UTC surface analysis and satellite imagery through 0215 UTC. ...TROPICAL WAVES... A tropical wave with axis along 82W north of 03N is moving westward at 10-15 kt. Scattered moderate convection is occurring over much of northern Panama. Otherwise, only isolated showers and thunderstorms are noted near the wave axis. It is possible that this activity may increase during the overnight hours as the wave moves through a very moist and unstable environment as observed in latest TPW satellite animation and in water vapor imagery. A tropical wave with axis along 88W/89W north of 03N is moving westward at 10 to 15 kt. This wave is also moving through a very moist and unstable environment. A the present time, only scattered moderate convection is seen within 60 nm west of the wave axis from 09N to 10N. Scattered moderate convection is enhanced by the northern part of the wave over western Honduras as it moves westward toward the coast. A rather well-defined tropical wave with axis along 104W from 04N to 17N is moving westward around 13 kt. A 1008 mb low is analyzed along the wave axis near 14N104W. Although the shower and thunderstorm activity associated with this system have become slightly better organized since yesterday, latest satellite imagery shows that the activity earlier observed today has decreased. The remaining activity consists of scattered moderate isolated strong convection within 180 nm west of the wave axis from 05N to 09N, and also within 120 nm west of the wave axis from 12N to 17N. Strong gusty winds may occur in and near this convective activity, especially with any additional outflow boundaries that may race away from this activity. According to the latest NHC Tropical Weather Outlook, some development of this system is possible during the next day or so before environmental conditions become less conducive over the weekend while it tracks in a west-northwestward motion. A tropical wave with axis along 130W from 03N to 16N is moving westward at about 15 kt. This wave is passing to the southwest of a mid to upper-level anticyclone centered near 22N122W. A possible weak mid-level cyclonic circulation is identified near 08N130W. Scattered moderate convection is within 60 nm west of the wave axis from 09N to 10N. Isolated showers and thunderstorms are elsewhere within 120 nm either side of the wave axis. This activity may possibly increase during the late night hours. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 09N79W to 09N90W to low pressure near 14N104W 1010 mb and to 10N110W to 12N120W to 11N128W. The ITCZ extends from 11N131W to beyond 10N140W. Scattered moderate to strong convection is within 180 nm south of the monsoon trough between 107W and 111W. Scattered moderate convection is within 30 nm of the trough between 92W and 95W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... High pressure west of Baja California will build southeastward through Fri night, allowing for fresh northwest winds over the offshore waters north of Cabo San Lazaro. Moderate to fresh southeast to south winds are expected across the central and southern Gulf of California this weekend. Large long-period south to southwest swell will reach the coast of southern Mexico Fri night, and continue into Mon. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... The monsoon trough remains relatively weak near 10N with the associated gradient allowing for only gentle to moderate south to southwest winds south of trough and light to gentle winds north of the trough. Little change is expected the next few days. Large long-period southwest swell has begun to propagate through the far southern waters today east of 120W. Wave model guidance suggests that this swell will reach the coast of Central America on Fri, and persist through Sun before it begins to slowly decay Sun night into early next week. REMAINDER OF THE AREA... High pressure of 1022 mb is centered near 32N130W, with a ridge extending southeastward to near the Revillagigedo Islands. The pressure gradient between the area of high pressure and a tropical wave near 130W is resulting in fresh to strong east to southeast winds within 180 nm east of the wave from 06N to 10N, with wave heights in the range of 8 to 10 ft. The tropical wave will continue moving westward through the next 48 hours. These winds will remain about the same strength through Sat as the wave moves farther away from the ridge axis. The wave heights may lower briefly to below 8 to 10 ft, but then reach 8 to 10 ft again late on Sat from 10N to 15N west of 136W. Outside of this area, winds are 20 kt or less, and wave heights are 8 ft or less under a stable atmospheric environment as noted by the stratocumulus clouds in the satellite imagery. Southerly swell that has already propagated across the equator is forecast to cover much of the forecast waters to south of 14N and east of 115W by Fri before it begins to decay. $$ Aguirre