448 AXPZ20 KNHC 070341 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Sat Aug 7 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 0000 UTC surface analysis and satellite imagery through 0300 UTC. ...SPECIAL FEATURES... A tropical wave extends along 104W from 01N to 19N. A 1009 mb surface low is analyzed along the wave axis near 15N104W. Scattered moderate convection prevails north of 10N between 102W and 110W. This activity is beginning to show signs of organization. Environmental conditions are conducive for additional development, and a tropical depression is expected to form late this weekend or early next week while the system moves west- northwestward at about 10 kt. The chance for tropical formation through the next 48 hours is medium. Please refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details. ...TROPICAL WAVES... A tropical wave extends from 01N to 16N with axis near 84W, moving W at 10 to 15 kt. Scattered moderate convection is N of 03N E of 91W. A tropical wave extends from 01N to 18N with axis near 120W, moving W at 10 to 15 kt. Scattered showers are noted from 08N to 12N where the wave meets the monsoon trough. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N84W to 15N104W to 10N123W. The ITCZ extends from 10N123W to 09N134W. Scattered moderate convection prevails from 03N to 18N and E of 110W, and from 06N to 11N between 122W and 130W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Refer to the Special Features section above for details on the tropical wave/low pres system developing a couple of hundred miles south of the coast of southwestern Mexico. A weak pressure gradient supports light to gentle variable winds along the Baja California offshores with seas to 4 ft. These conditions are forecast to prevail through Sun evening when moderate NW winds are forecast to develop along the coastal waters while NE moderate winds are forecast near the Revillagigedo Islands as a low approaches from the SE. The tail of a surface trough extending from a low located near the border between Arizona and California continues to support moderate to fresh SE winds in the northern portion of the Gulf of California with seas to 4 ft. Light to gentle variable winds are elsewhere with seas to 5 ft in SW swell. A broad area of low pressure centered near 15N103W is generating scattered showers and tstms over the Guerrero and Jalisco offshore waters. This low has the potential to become a tropical depression early next week while the system moves WNW parallel to and offshore of the coast of southwestern Mexico. Winds and building seas associated with this area of low pressure will begin to affect the aforementioned offshore waters on Sat. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Gentle to moderate south-southwest winds are occurring south of the monsoon trough. To the north of the monsoon trough, gentle winds prevail, with some locally moderate winds near the Papagayo region. Seas are in the 3 to 5 ft range in long period mixed swell. For the forecast, surges of locally fresh winds are likely over the offshore waters north of Costa Rica during the overnight hours through the weekend as convection over Central America propagates offshore. Otherwise, fairly tranquil winds should prevail through the forecast period. A moderate southerly swell may propagate across the waters west of Ecuador during the weekend, with another set early next week. REMAINDER OF THE AREA... Post-tropical low Jimena is centered west of our area near 17.9N 140.8W as of 07/0300 UTC. An area of fresh winds and seas ranging between 8 and 11 ft prevails west of 138W through Sat morning. Latest scatterometer data indicate that the remnant low of Hilda has opened into a trough with fresh to locally strong winds from 21N to 25N between 134W and 137W. Seas in the vicinity of the trough are 8 to 9 ft. Surface high pressure NW of the area extends a ridge SE to just N of the features described above. The pressure gradient between the ridge and both areas of low pressure supports moderate to locally fresh NE to E winds mainly N of 26N and W of 120W. Seas in this region fluctuate between 5 to 7 ft. $$ ERA