000 AXPZ20 KNHC 182205 RRA TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Wed Jan 18 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 2145 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from low pressure of 1011 mb over northwest Colombia westward to central Costa Rica, then southwestward to 06N91W and northwestward to 08N100W, to low pressure near 07N105W 1012 mb and to 06N110W, where latest scatterometer data indicates that it transitions to the ITCZ and continues to 05N118W to 07N128W and to 06N129W to beyond 06N140W. Scattered moderate convection is within 60 nm north of the ITCZ between 130W-139W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Recent scatterometer data depicts generally gentle to moderate northwest to north winds across the offshore waters of Baja California under the influence of a ridge. A small pocket of fresh northwest winds is near and just offshore Cabo San Lazaro. Light to gentle north winds are noted in the southern Gulf of California, and between Los Cabos and Las Marias Islands. Light and variable winds persist in the Gulf of Tehuantepec. Latest altimeter data passes reveal seas in the range of 8-11 ft north of 10N and west of about 110W. For the forecast, the above mentioned ridge will dominate the offshore forecast waters of Baja California through at least Fri, producing mainly gentle to moderate northwest to north winds. Light to gentle winds will persist in the Tehuantepec region through the rest of the week along with 4-6 ft seas due to west-northwest swell. Long-period northwest swell will continue to propagate over the offshore waters of the Baja California Peninsula through Thu while subsiding, however, lingering northwest swell will be over the waters west of Baja California Norte through Fri, with seas of 8-10 ft. A cold front will sweep southward across the Gulf of California and the Baja California Peninsula Fri through Sat. Looking ahead, winds are forecast to increase in the Gulf of California during the upcoming weekend as the gradient tightens over the area after passage of the aforementioned cold front as strong high pressure builds east-southeast in its wake. As a result, fresh to locally strong northwest winds are forecast to funnel through the Baja California gaps and into the offshore waters, especially between Punta Eugenia and Cabo San Lazaro. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... A recent ASCAT data pass showed moderate to fresh northeast winds in the Gulf of Papagayo. Gentle northerly winds are in the Gulf of Panama, reaching downstream to near 05N, while light and variable winds are now near the Azuero Peninsula. Light to gentle winds prevail elsewhere based on scatterometer data. Seas of 5-8 ft between Ecuador and the Galapagos Islands are due to long-period northwest swell propagating through those waters as noted in the most recent altimeter data pass over this part of the area. Elsewhere, seas are generally in the 4-6 ft range. A trough extends from low pressure of 1011 mb over northwest Colombia southwestward to the coast of Colombia near 07N78W and continues southwestward to near 04N81W. Scattered moderate convection is seen from 04N to 06N between 77W-81W. For the forecast, mainly moderate to fresh winds will prevail in the Papagayo region through Fri, then winds are forecast to increase again to fresh to strong speeds Fri night and Sat. Gentle to moderate winds are expected in the Gulf of Panama, and east of the Azuero Peninsula through the rest of the week. Seas of 5-8 ft due to a long-period northwest swell west of Ecuador, including the waters west of the Galapagos Islands, will subside slightly to 5-6 ft tonight and change little through Fri. Winds will be moderate or weaker elsewhere through at least the next several days. REMAINDER OF THE AREA... A 1026 mb high center is analyzed north of the area near 33N133W. High pressure covers the area north of 10N and west 110W, and is controlling the weather pattern throughout. The associated gradient supports mainly gentle to moderate northeast to east trade winds across this part of the area, except for light and variable winds north of 26N and west of 127W and mostly fresh northeast winds from 07N to 20N west of 128W. Seas over this area are in the 8-10 ft range due to a long-period northwest swell. For the forecast, long-period northwest swell will continue to propagate across most of the forecast waters through Thu, while slowly decaying allowing for a subsiding trend of the seas. High pressure will dominate most of the forecast waters north of about 15N and west of 10W for the rest of the week. The high pressure will strengthen some during the upcoming weekend, with the resultant gradient increasing the trade wind flow over this part of the area. The next swell event is expected to reach the far northwest corner of the discussion area by Fri evening. $$ Aguirre