000 AXPZ20 KNHC 160142 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 113 UTC Tue Jul 16 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 0130 UTC. ...TROPICAL WAVES... A travel wave with axis along 90W from 03N to El Salvador is moving west at 10 to 15 kt. Visible and infrared imagery continues to show some broad cyclonic circulation in its vicinity. Convection this evening is mainly confined to land areas of Central America at this time, but the wave is engulfed in plenty of moisture and instability, and showers and thunderstorms may form tonight closer to the wave access. The environmental conditions in the area are forecast to become conducive for gradual development later this week, and the 0000 UTC NHC Tropical Outlook indicates there is a 40 percent chance of tropical depression formation toward the end of this week as it moves west at 10 to 15 kt, well south of the southern coast of Mexico. A tropical wave with axis 100W from 03N to 16N continues to weaken and become less defined this afternoon. Convection associated with this wave has diminished and the feature will likely dissipate on Tuesday. A more organized wave in a better moist and unstable environment has an axis near 110W from 03N to 17N. This wave is moving west around 15 kt and is producing a wide areas of numerous showers and thunderstorms with isolated strong convection from 06N to 15N between 102W and 112W. Gusty winds are likely occurring with the stronger thunderstorms. Another tropical wave with axis along 131W from 02N to 15N is moving west at 10 to 15 kt. Scattered showers and thunderstorms with isolated strong convection exists within about 240 nm E of the axis from 05N to 11N. This wave should enter the Central Pacific Thursday. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from a 1010 mb low along the northern coast of Colombia across Panama and Costa Rica to near 09N89W to 08N100W to 13N120W, where trade winds suggest it transitions into to the ITCZ. The ITCZ then continues to 10N130W, is broken up by the aforementioned tropical wave near 131W, then continues from 09N133W to beyond 08N140W. Other than areas of convection described above in the Tropical Waves section, little convection is occurring . OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Earlier scatterometer passes showed light to gentle winds over most of the waters, due to a weak pressure pattern. After altimeter imagery depicted wave heights for most areas between 5 and 7 ft, as long period southwesterly swell has been slow to diminish A trough over the Gulf of California will strength over the next few days as low pressure deepens over the southwest U.S. The result will be fresh to locally strong southerly winds across the northern Gulf of California Tuesday and all Gulf waters Wednesday. North and northwest swell being generated by gales off the west coast of the United States will propagate into waters west of Baja California Norte Tuesday into Wednesday, mixing with southwest swell and building wave heights to 8 to 9 ft. This swell should decay Thursday and Friday. Some seas of up to 8 feet may affect waters offshore southern Mexico midweek as fresh to strong easterly breezes in the Gulf of Papagayo region generates higher waves. Winds in the Gulf of Tehuantepec may also pulse to strong mid to late week as a tropical wave approaches Central America from the east. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gentle to moderate east to northeast winds are indicated by earlier scatterometer data off Central America, north of the monsoon trough. Moderate to fresh south to southwest winds are occurring south of the trough, off Colombia and Ecuador. For waters near the Gulf of Papagayo, fresh to possibly strong easterly winds will pulse during the evenings through mid-week, leading to seas of around 8 ft. Long-period cross-equatorial southwest swell will continue to lead to seas of 5 to 7 feet across the waters, with wave heights south of the equator reaching 8 to 9 feet at times into late week. REMAINDER OF THE AREA... A trough of low pressure with axis from 21N120W to 15N123W continues to weaken as it drifts westward. Afternoon scatterometer data depicts moderate northeast winds on the northwest side of this trough. No convection is occurring with this trough and weakening should continue until Tuesday night, when the feature is forecast to dissipate. A nearly stationary high pressure is centered north of the forecast area at 33N140W, with a pressure of 1025 mb. A ridge axis extends southeastward to 30N135W just southwest of the southern tip of Baja California Sur. Moderate to fresh northeasterly trades are occurring southwest of the axis and north of the monsoon trough and ITCZ. Long-period southwest swell continues across much of the waters south of 20N. Altimeter passes this afternoon continue to show wave heights of 8 to 9 ft to the south of 18N and west of 110W. The swell will gradually decay through mid-week, allowing seas to gradually subside. $$ KONARIK