727 AXPZ20 KNHC 011608 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Thu Jul 1 2021 Tropical Weather Discussion for the eastern Pacific Ocean from 03.4S to 30N, east of 120W including the Gulf of California, and from the Equator to 30N, between 120W and 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. ...TROPICAL WAVES... A tropical wave is near 83W/84W north of the Equator into Costa Rica, moving west at around 10 kt. Scattered moderate convection is noted near the wave axis and along the monsoon trough west of Costa Rica from 09N to 11N east of 90W. A tropical wave is near 102W north of 02N to SW Mexico, moving west at 5 to 10 kt. Scattered moderate and isolated strong convection is noted from 06N to 09N between 98W and 101W, and north of 11N between 95W and 101W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N83W to 13N105W to 10N130W. The ITCZ continues from 10N130W to 09N140W. Aside the convection associated with the tropical waves, scattered moderate convection is from 09N to 11N between 105W and 120W, and from 06N to 09N west of 135W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A weak pressure gradient supports mainly light to gentle NW-N winds west of the Baja California peninsula with locally moderate winds along the coast. Seas are in the 4 to 6 ft range in mixed long period swell. Gentle to moderate SE winds are noted over the Gulf of California with slight seas. Mainly light to gentle variable winds with seas in the 4 to 6 ft are elsewhere from Chiapas to Jalisco offshore waters. For the forecast, light to gentle variable winds will dominate the offshore waters through early next week. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Scattered showers and thunderstorms are active over the offshore waters from Costa Rica to El Salvador, related to the interactions of the monsoon trough with the tropical wave passing through the region, in a moisture-rich environment. Moderate to locally fresh NE to E winds are over the Papagayo region with seas to 6 ft. Light to gentle variable winds are elsewhere north of the monsoon trough with seas 3 to 5 ft in mixed long period swell. Moderate S-SW winds with seas of 4 to 6 ft dominate the waters south of the monsoon trough. For the forecast, moderate to locally fresh winds will continue in the Papagayo region into Fri with gentle to moderate winds elsewhere north of the monsoon trough continuing through the end of the weekend. Except in the area of convection associated with the tropical wave, gentle to moderate southerly flow will prevail south of the monsoon trough through Mon. REMAINDER OF THE AREA... A surface trough, related to an upper low, is evident from roughly 15N to 20N between 125W and 130W. This is supporting moderate NE winds north of 10N and west of 130W, between the trough and high pressure north of the area, with 5 to 6 ft seas. The trough is also breaking up the ridge and allowing minimal trade wind flow farther south into the tropics. Moderate southerly flow is noted roughly south of 10N, reaching moderate to fresh SW winds between 95W and 110W where 6 to 8 ft seas are evident. The enhanced SW flow is due to lowering surface pressure in this area along the monsoon trough, related in part to the tropical wave passing westward over the region. Scattered showers and a few thunderstorms are active along the monsoon trough except for between roughly 120W and 135W, due to subsident flow aloft on the west side of the upper low centered near 20N125W. Little change in winds is forecast for the remainder of the week into the weekend. A moderate southerly swell will reach the equator by the end of the week into the weekend, building seas to around 8 ft there. $$ Christensen