000 AXPZ20 KNHC 121559 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Sun Mar 12 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 1200 UTC surface analysis and satellite imagery through 1500 UTC. ..SPECIAL FEATURES... Heavy Rainfall over Ecuador: The large-scale environment remains favorable for continued periods of heavy rainfall over portions of NW South America through late this week. Although the threat of heavy rain will exist on a daily basis, the risk is higher in Ecuador from late today through Tue morning, when very heavy rain and significant flash flooding is possible. After Tuesday, the rain in Ecuador should diminish in intensity slightly, while the biggest threat shifts southward into Peru. Please refer to your local meteorological service for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 07N90W to 03N100W to 02N112W. The ITCZ extends from 02N113W to 01N140W. Scattered moderate convection is noted from 04N to 10N between 84W and 90W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... High pressure of 1021 mb centered near 26N128W extends a ridge southeastward to the Baja California offshore waters. Fresh NNW winds prevail west of Baja California Sur and Baja California Norte, south of 29.5N. To the north of 29.5N, winds are moderate from the NNW. Moderate NW winds are over the southern Gulf of California, while gentle and variable winds prevail over the northern Gulf. Gentle winds prevail elsewhere east of 110W, while moderate northerlies prevail to the SW of Cabo San Lucas, extending offshore. Seas are 5-7 ft to the west of Baja California and 2-3 ft in the southern half of the Gulf of California. Seas are 3-4 ft elsewhere, except 1-2 ft in the northern Gulf of California. For the forecast, fresh to locally strong NNW winds will prevail near, and within 120 nm west of the coast of Baja California through Mon. Surface high pressure will move over the area Tue, leading to gentle winds. Moderate NW winds will prevail in the southern Gulf of California through Mon night, pulsing to fresh from late this afternoon through this evening. Quiescent conditions are expected elsewhere through Tue. A cold front will reach the Baja California Norte offshore waters early Wed, and move SE over the northern Gulf of California late Wed, then weaken Wed night over the central Gulf of California. The front should bring fresh winds for the waters west of Baja California and the northern Gulf of California. The front will also bring increased NW swell to the Baja California Norte waters. The next Gulf of Tehuantepec gap wind event is forecast to begin early Wed with fresh to strong N winds becoming strong to locally near-gale force Wed evening/night. 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 over NW South America through late next week. Numerous moderate and isolated strong convection is noted on satellite imagery offshore of Costa Rica from 05.5N to 10.5N between 85W and 89W. Moderate ENE to E winds are occurring over the Gulf of Papagayo region with seas 3 to 4 ft. Moderate SE winds are offshore southern Costa Rica and western Panama with seas 4 to 5 ft. Elsewhere, light to gentle variable winds prevail with seas of 3-6 ft, highest along the equatorial offshore waters between Ecuador and the Galapagos Islands. For the forecast, moderate NE to E winds in the Gulf of Papagayo and moderate SE winds across the Costa Rica offshore waters will diminish to light to gentle by late this afternoon. Light to gentle variable winds are expected elsewhere through the remainder of the forecast period. The heavy showers offshore Costa Rica will migrate inland Mon, producing periods of heavy rain over Costa Rica through early Tue. REMAINDER OF THE AREA... A 1021 mb high pressure is centered near 26N126W. Light to gentle variable winds are being provided by the high to the N of 21N and W of 119W where decaying W to NW swell continues to support seas of 8 to 10 ft, observed by recent altimeter data and drifting buoys. South of 21N to 04N and W of 115W, winds are moderate from the NE and seas are in the 6 to 9 ft range, highest between 125W and 140W. For the forecast, little change is forecast through tonight. Current NW swell across the western waters will continue to push southeastward while gradually diminishing, dropping below 8 ft by Mon. Fresh to strong SW winds ahead of a cold front should move from west to east across the waters north of 25N on Mon through early Tue. The cold front will extend from 30N133W to 25N138W early Tue, and from 30N117W to 25.5N132W early Wed before weakening and dissipating late Wed. Otherwise, a new frontal boundary will approach the NW forecast waters Wed evening and will support fresh to strong winds along with building seas north of 27N and west of 130W through Thu evening. $$ Hagen