000 AXPZ20 KNHC 072201 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Fri Jul 7 2023 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 1800 UTC surface analysis and satellite imagery through 2100 UTC. ...SPECIAL FEATURE... Offshore of Southwestern Mexico (EP93): An elongated area of low pressure extending from a few to several hundred miles SW of southwestern Mexico is showing signs of improved organization this afternoon. At this time, scattered to locally numerous moderate to strong convection prevails from 10N to 18.5N between 101.5W and 112.5W. Satellite derived winds from around midday showed a broad zone of 20-25 kt winds wrapping around the circulation of this system, from the SE portions to the N, along the coast of Mexico. Seas of 10 to 11 ft are estimated within this area of winds from 11N and 15N between 103W and 107W. Environmental conditions are forecast to be conducive for improved organization of this system, and a tropical depression will likely form during the next day or so, while it moves generally W-NW and remains offshore of the coast of Mexico. In anticipation of this, a gale warning has been issued for the outer offshore waters of SW Mexico beginning Sat afternoon. There is a high chance of tropical formation in the next 48 hours. Refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details. ...TROPICAL WAVES... A Caribbean tropical wave along 85W-86W extends into the far eastern Pacific Ocean, and is moving westward at 10 kt. Associated convection is seen along the base of the wave and is described below. A tropical wave is along 106W-107W from 07N northward, moving W at 10 kt. This wave is moving into an area of elongated low to mid level cyclonic turning, associated with EP93. Associated convection is described below. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N75W to 09N88W to 15.5N104W to low pressure 1006 mb near 14.5N107W to 08.5N126W. The ITCZ extends from 08.5N126W to 06.5N134W to beyond 07.5N140W. Scattered moderate isolated strong convection is noted N of 03.5N E of 84W. Scattered to locally numerous moderate to strong convection is noted from 05N to 14N between 86W and 98.5W, and from 10N to 18.5N between 101.5W and 112.5W. Scattered moderate convection is noted within 210 nm S of trough between 111W and 125W, and within 180 nm N of the ITCZ between 133W and 137W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A surface ridge dominates the offshore forecast waters of Baja California N of 18N. Moderate NW winds are noted in the Baja California Norte offshore waters with gentle to moderate NW winds elsewhere across the Baja California offshore waters. Seas remain 5-7 ft in a mix of northerly and southerly swell. In the Gulf of California, gentle to moderate southerly winds prevail with seas ranging 2-4 ft except to 5 ft in southerly across the entrance. Gentle to moderate winds are noted elsewhere across the Mexico offshore waters N of Cabo Corrientes with 5-6 ft seas in southerly swell. Winds and seas have increased across the offshore waters between Cabo Corrientes and Acapulco today as a tropical wave is moving into an area of disturbed weather (EP93) across the offshore waters there. Midday satellite derived winds showed E-SE winds of 20-25 kt from the coast to 120 nm offshore across this area, and similar S to SW winds from 07N110W into the near shore waters. Seas of 8 to 11 ft are assumed across these waters. Scattered to locally numerous convection is noted in the offshore waters east of 111W associated with the monsoon trough, Special Feature EP93, and the tropical wave described above. Some of the stronger thunderstorms are producing strong gusty winds. For the forecast, a broad surface ridge will persist across the regional waters through early next week. Winds off of Baja California Norte will pulse to fresh at night through the weekend. A tropical depression is likely to from from EP93 within the next day or so while it moves generally W-NW and offshore of the coast of Mexico. Gale warnings are now in effect for the outer offshore waters W of 108.5W. Large southerly swell is expected to be generated by this system, and will move into the entrance to the Gulf of California and the offshore waters of Baja Sur Sun through Mon. Another area of low pressure is expected to form a few hundred miles south of the southern coast of Mexico Sun or Mon. Some gradual development of this system is expected while it moves westward. This second system has a low chance of tropical formation in the next 48 hours and a high chance in the next 7 days. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Light to gentle winds are noted north of 10N. Seas are 6-7 ft in strong south-southwest swell. Gentle to moderate SW to W winds are present south of 10N. Seas are 6-8 ft in southerly swell. For the forecast, gentle to moderate winds will prevail over the next several days. Strong southerly swell will gradually subside across the regional waters tonight through Sat. Low pressure is expected to form S of Tehuantepec late Sun or Mon leading to freshening winds across the waters W of 90W. Fresh gap winds across the Papagayo region starting Sun will pulse to strong at night Mon through Wed. ...REMAINDER OF THE AREA... High pressure prevails north of 10N, centered on a 1029 mb surface high near 41N149W. Gentle to moderate northeast winds and seas of 5-8 ft in southerly swell prevail north of the ITCZ and west of 120W. To the south of the ITCZ, gentle to moderate S winds are noted. Large swell from the Southern Hemisphere has peaked in the past 12-18 hours, and continues to produce seas of 7-8 ft across the waters S of 10N and W of 90W. For the forecast, high pressure will remain in place over the northern waters through Sat, then shift slightly SE Sun through Mon. This will increase winds N of the ITCZ to moderate to locally fresh, with seas in the 5-7 ft range. Cross- equatorial southerly swell will in the southern waters will subside through Sat. Northerly swell will move into the waters E of 125W Sun and Mon to raise seas there to around 8 ft, then combine with SE to E swell generated by the potential tropical system, EP93, across the waters E of 130W on Mon and Tue. $$ Stripling