000 AXPZ20 KNHC 231530 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1530 UTC Tue Jun 23 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 1200 UTC surface analysis and satellite imagery through 1500 UTC. ...SPECIAL FEATURES... Showers and thunderstorms associated with an elongated area of low pressure centered near 12N116W have not become any better organized since yesterday. Recent satellite imagery shows a small area of scattered strong convection from 13N to 15N between 116W and 118W. Environmental conditions are forecast to remain conducive for gradual development over the next couple of days, but the disturbance is forecast to move over cooler waters after that time which should inhibit further development. This system has a medium chance of tropical cyclone formation during the next 48 hours. A small area of low pressure centered near 10.5N130W continues to produce an area of cloudiness and showers. No significant convection is associated with the system this morning. Although the shower activity has become a little less organized overnight, environmental conditions appear conducive for gradual development, and this system is likely to become a tropical depression during the next few days while it moves slowly westward. This system has a medium chance of tropical cyclone formation during the next 48 hours, and a high chance during the next five days. Please refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details. ...TROPICAL WAVES... The southern portion of a Caribbean Sea tropical wave is along 81W north of 02N, moving westward at 20-25 kt. Numerous moderate and scattered strong convection is noted north of 04N and east of 81W to the coast of Colombia. A tropical wave axis is along 91W north of 06N, moving westward at 20 kt. Scattered moderate and isolated strong convection is noted from 09N to 12N within 180 nm east of the wave axis. A tropical wave axis is along 98W north of 05N, moving westward at 10-15 kt. This wave remains well-defined in precipitable water imagery and local wave diagnostic tools. Numerous moderate and scattered strong convection is occurring north of 10N within 240 nm east of the wave axis. Scattered moderate and isolated strong convection is noted from 05N to 10N within 180 nm of the wave axis. Environmental conditions are expected to be conducive for development, and the system is likely to become a tropical depression in a few days while it moves west-northwestward parallel to the coast of Mexico. This system has a high chance of tropical cyclone formation during the next five days. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 10N76W to 07N83W to 13N104W to 1009 mb low pressure near 12N116W to 09N122W to 1009 mb low pressure near 10.5N130W to 08N140W. Numerous moderate and isolated strong convection is occurring within 120 nm of the monsoon trough between 118W and 127W. Scattered moderate convection is noted within 120 nm of the monsoon trough between 99W and 104W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A high pressure ridge remains positioned well offshore of Baja California this morning, while a low pressure trough is analyzed along the Baja peninsula near the Gulf of California. Gentle to moderate NW winds prevail over the Baja offshore waters, with gentle to moderate SE flow across the central and southern Gulf of California. Recent altimeter passes show 4-6 ft seas south of Baja California Sur and near the entrance to the Gulf of California. Elsewhere, mainly gentle winds continue off the coast of southern Mexico, with 5-7 ft seas in SW swell. Offshore high pressure will weaken later this week, allowing winds offshore of Baja California to diminish Thu through Sat. Winds and seas will increase off the coast of southern Mexico late this week and into the weekend as a couple of low pressure systems with the potential for tropical cyclone formation move parallel to the coast of Mexico. Please see the NHC Tropical Weather Outlook for the latest updates. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh easterly gap winds prevail over the Papagayo region this morning. Gentle to moderate SW monsoon flow continues south of the monsoon trough, with light and variable winds elsewhere north of the trough. Seas across much of the region remain 5-7 ft as cross-equatorial SW swell continues moving across the waters. Moderate to fresh winds will pulse in the Papagayo region through Sat, and possibly strengthen Thu night into Fri as low pressure forms off the coast of southern Mexico. Elsewhere, moderate to occasionally fresh monsoon flow will prevail across the southern offshore waters for the next several days. REMAINDER OF THE AREA... Please see the Special Features section above for more details on the potential for tropical cyclone development later this week. A ridge extends southeastward across the northern waters from high pressure analyzed near 36N135W this morning. The gradient between this ridge and the monsoon trough is maintaining moderate to fresh trades generally south of 20N and west of 120W, with 7-9 ft seas based on recent altimeter data. Locally strong winds and seas 8 ft or greater are likely occurring near the monsoon trough lows discussed above in the Special Features section, or generally along the monsoon trough between 110W and 130W. Southerly swell will continue decaying over the southern waters today. Another set of cross-equatorial southerly swell may build seas over the southern waters late this week. Additionally, monsoon flow will likely strengthen as two low pressure systems with the potential for tropical cyclone development form off the coast of southern Mexico later this week and this weekend. This will likely create hazardous winds and seas off southern Mexico. $$ B Reinhart