000 AXPZ20 KNHC 131550 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Sun May 13 2018 Tropical Weather Discussion for the eastern Pacific Ocean from the Equator to 32N, east of 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. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 08N80W to 07N95W to 10N102W to low pressure near 11N114W 1009 mb to 06N122W to another 1011 mb low near 13.5N130W to 09N136W. The ITCZ continues from 09N136W to beyond 08N140W. Scattered moderate isolated strong convection is noted from 04N to 10N E of 95W to the coast of Colombia, and within 150 nm NW of a line from 14N111W to 08N118W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... The combination of low pressure over the southwestern United States that covers the northern and central Mexico, with high pressure that noses eastward towards northern Baja California continues to induce a tight pressure gradient over the northern Gulf of California and northern Baja California. This supports southwest winds of 20 to 25 kt. The gradient will relax enough to allow for these winds to diminish to the gentle to moderate speeds, with seas of 3 to 5 ft by this afternoon. Winds over the rest of the gulf will be light to gentle. Then, winds are forecast to increase to 15-20 kt across the northern Gulf of California tonight and Mon night. Northerly gentle to moderate winds will remain over the offshore waters W of Baja California through Tue afternoon, then increase to fresh to strong winds beginning Wed night as high pressure W of Baja California strengthens slightly and while at the same time it builds east-southeastward. Seas of 6 to 8 ft in long period NW swell, will subside to 5 to 7 ft tonight. Farther south in the Gulf of Tehuantepec, mainly light to gentle winds are expected today, with seas of 5 to 7 ft in long period southerly swell. Winds will briefly become NW to N at moderate to fresh speeds early on Mon before becoming moderate south to southwest winds during the afternoon. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: light to gentle winds will dominate the gulf most of the forecast period with seas of 4 to 6 ft in long period SW swell. Gulf of Panama: Gentle to occasionally moderate SW winds are forecast during the next several days, with seas of 4 to 6 ft in long period southerly swell through Mon before subsiding slightly Tue. REMAINDER OF THE AREA... A ridge extends from a 1024 mb high pressure, centered well north of the area near 44N136W, southeastward to near the Revillagigedo Islands. Low pressure, remnants of recent Tropical Depression One-E, is nearly stationary near 13.5N130W with a central pressure of 1011 mb. The small cyclonic circulation of the low is clearly exposed, and will become ill-defined with time. Latest satellite imagery shows a small cluster of moderate convection well to the northeast of the low covering the waters from 13N to 15N between 125W and 128W. The low is forecast to begin to drift southward this afternoon through tonight as the high pressure ridging to its N begins to build southward. The low is then forecast to open up to a trough Mon afternoon. Northwest swell producing seas with peak values of up 10 ft will continue to propagate across the forecast waters reaching as far south as 22N by early this afternoon before decaying below 8 ft by tonight. As previously mentioned, a 1009 mb low is embedded within the monsoon through near 11N114W. Latest satellite imagery shows a cluster of moderate to isolated strong convection within about 180 nm N quadrant of low center. A diffluent pattern aloft is helping to support this convective activity. According to the global models, the low should persist over the next 48 to 72 hours as it tracks in a general west to west-southwest direction. $$ GR