000 AXPZ20 KNHC 070716 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Tue Mar 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 0600 UTC surface analysis and satellite imagery through 0650 UTC. ..SPECIAL FEATURES... The large scale environment is favorable for heavy rainfall over portions of NW South America through Saturday. Five day rainfall totals may exceed 250 mm over interior portions of Piura and northern Lambayeque in Peru, and in the Gulf of Guayaquil region in southern and central Ecuador. In addition, above average precipitation is expected in western Colombia with rainfall totals in excess of 200 mm possible, and in southern Costa Rica where rainfall totals may exceed 150 mm. Please refer to your local meteorological service for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from Costa Rica near 09N84W to 03N93W to 01S108W. The ITCZ extends from 02S114W to 02S120W to 00N140W. Scattered moderate isolated strong convection is noted within 180 nm either side of the trough east of 99W. Scattered moderate convection is noted from 01S to 03S between 92W and 96W, and from 00N to 03N between 120W and 126W. Similar convection is noted within 90 nm of the Ecuador, including the Gulf of Guayaquil. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A ridge of high pressure extends northwest to southeast across the offshore waters of Mexico. Moderate to fresh winds are noted west of the Baja California peninsula, except locally strong within 60 nm of shore from near Punta Eugenia northward. Elsewhere, gentle to moderate winds prevail per recent ASCAT scatterometer data. Seas are in the 8 to 11 ft range in NW swell offshore Baja California Norte, 6 to 8 ft offshore Baja California Sur, and 3 to 5 ft elsewhere over the open waters off Mexico per recent altimeter passes. Over the Gulf of California, seas are in the 1 to 2 ft range. Some haze continues to be reported at coastal sites of southern Mexico. For the forecast, fresh to strong NW to N winds will prevail through the week and into the weekend near and north of Punta Eugenia. A surge of moderate to fresh NW winds will be in the central and southern Gulf of California Thu night through Fri. Winds will be mainly moderate or weaker elsewhere through the week and into the weekend. NW swell will build offshore Baja California through mid-week with seas of 7 to 11 ft. Little change in seas is forecast elsewhere. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Please refer to the Special Features section for details on the potential for heavy rainfall. Fresh to strong offshore winds and 6 to 7 ft seas are in the Gulf of Papagayo. Gentle to moderate winds are from the Gulf of Panama to the Azuero peninsula. Elsewhere, light to gentle winds prevail. Outside of the Papagayo region, seas are in the 3 to 6 ft range in S to SW. Some haze continues to be reported at coastal sites of Guatemala and El Salvador. For the forecast, fresh to locally strong NE to E winds will pulse offshore southern Nicaragua including the Gulf of Papagayo through Wed, then pulse to moderate to fresh through the end of the week and into the weekend. Seas will reach near 7 ft during the period of fresh to strong winds. Winds will be moderate or weaker elsewhere, along with seas of 3 to 5 ft in S to SW swell. REMAINDER OF THE AREA... A trough/warm front extends to 140W northwest of 23N with associated locally fresh to strong winds north of 23N and west of about 137W. Otherwise, high pressure dominates the waters north of the ITCZ which is suppressed to the south of the Equator. The pressure gradient between this area of high pressure and lower pressure in the vicinity of the ITCZ is supporting gentle to moderate winds, locally fresh from 15N to 19N between 131W and 134W per recent ASCAT scatterometer data. Large NW to N swell of 8 to 11 ft is north of about 19N. Seas are mainly 5 to 7 ft in NW to N swell elsewhere, except 4 to 6 ft mixed with SW swell east of 100W. For the forecast, low pressure and associated fronts west of 140W are expected to continue to bring fresh to strong E to SE winds and seas of 9 to 11 ft over a portion of the NW waters through tonight. A cold front may approach 30N140W by early Thu, with fresh to strong SW winds and seas of 8 ft or greater ahead of it spreading southeast of 30N through Thu night. The seas of 8 ft or greater will continue eastward reaching to near 125W by the weekend, and with seas of 12 ft or greater briefly north of 20N and west of 136W Fri night into early Sat. Little change in winds is forecast elsewhere through the week and into the weekend. The large NW to N swell over the northern waters will spread seas of 8 ft or greater to near 15N by mid-week while gradually decaying. $$ Lewitsky