000 AXPZ20 KNHC 222127 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Mon May 22 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 2115 UTC. ...SPECIAL FEATURES... Western Colombia, Panama, and Costa Rica Excessive Rainfall: Convection continues to flare-up along the monsoon trough E of 95W to the coast of Colombia, and across parts of Colombia, Panama and Costa Rica. A favorable upper-level pattern in combination with the monsoon trough will continue to bring enhanced moisture through Wed, leading to the potential for additional heavy rainfall. This activity could lead to significant flooding in the region. Latest GFS moisture guidance suggests that present favorable pattern will continue through Wed. Please refer to the latest forecast products from your local or national meteorological service for additional information. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from northern Colombia near 10N75W to 09N90W and to 08N103W. The ITCZ extends from 08N103W to 07N115W to 05N130W and to 03N140W. Scattered moderate to isolated strong convection is seen from 03N to 08N between 80W- 85W, within 180 nm south of trough between 85W-92W and within 180 nm N of the ITCZ between 116W-123W. Scattered moderate convection is from 03N to 08N between 78W-80W, within 120 nm S of trough between 95W-98W and within 60 nm S of ITCZ between 123W-129W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A ridge dominates the offshore forecast waters of Baja California producing mainly moderate NW to N winds. A small area of fresh to strong NW winds is near and within 60 nm southwest of the southern tip of Baja California. Seas are 4-6 ft W of Baja California. Fresh W to NW winds are in the Gulf of Tehuantepec region and downwind to near 15N, with seas of 5-7 ft due to a long-period S swell. A recent altimeter pass just caught the western edge of these seas. In the Gulf of California, mainly light and variable winds prevail with seas of 1-3 ft, except 3-5 ft in south swell at the entrance to the Gulf. Light and variable winds are seen across the remainder of the Mexican offshore waters with sea heights of 4-6 ft primarily in SW swell. For the forecast, the fresh W to NW winds in the Gulf of Tehuantepec region will shift to northerly late tonight into early Tue before diminishing in the afternoon. Seas of 5-7 ft due to a long-period S swell are present in the Gulf of Tehuantepec region. Moderate to fresh S to SW winds are expected in the northern Gulf of California at night Tue through Thu ahead of a surface trough forecast to persist over the Baja California Peninsula. Seas of 6-8 ft in NW swell will gradually propagate across the outer offshore waters N of Cabo San Lazaro tonight through Thu. Reduced visibilities in haze are possible in the southern offshore waters due to smoke produced by agricultural fires. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Please see the Special Features section above for details about a heavy rainfall event affecting Colombia, Panama and Costa Rica. Fresh NE to E winds are occurring in the Papagayo region, and downwind to about 88W along with seas of 5-7 ft. Gentle N winds are in the Gulf of Panama with seas of 4-6 ft due to a long- period S swell. Gentle to moderate S to SW winds are noted elsewhere, except for SW to W winds from the Equator to 05N between 78W-82W along with seas of 5-7 ft due to a long-period S to SW swell. For the forecast, the fresh NE to E winds in the Papagayo region will diminish this afternoon, then develop as fresh SE winds tonight and diminish on Tue. Gentle to moderate winds will prevail across the remainder of the offshore waters. Long-period S to SW swell producing seas of 5-7 ft will continue to cross the Equator through Thu night. Heavy showers and thunderstorms will continue offshore Costa Rica, Panama and Colombia today. Reduced visibilities in haze are possible from the Guatemala to the Nicaragua offshore waters due to smoke produced by ongoing agricultural fires. Looking ahead, seas building to 8-10 ft in long-period SW swell are expected between Ecuador and the Galapagos Islands by Fri, with little change through Sat night. ...REMAINDER OF THE AREA... High pressure dominates the forecast area north of 12N and west of 110W. Mainly moderate anticyclonic flow is noted under the influence of this system, with seas generally in the 5-7 ft range. Gentle to moderate winds prevail south of the monsoon trough/ITCZ. An area of 8-9 ft seas due to a mix of NE and SW long-period swell is located from 07N to 12N between 117W-125W, and also from 08N to 12N between 137W-140W. For the forecast, a ridge will continue to dominate the region N of 10N and W of 110W through at least mid-week. Fresh to locally strong trade winds will prevail across the southern periphery of the ridge, especially west of 120W. Northerly swell, with seas in the 8-10 ft range, will begin to propagate across the northern forecast waters by this evening, covering the area N of about 25N between 119W-140W by Tue evening. The swell is forecast to decay on Thu. $$ Aguirre