000 AXPZ20 KNHC 120955 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Sat May 12 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 0600 UTC surface analysis and satellite imagery through 0930 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 08N79W to 10N95W to 09N113W to 08N120W to 10N125W. Latest scatterometer data indicated that the Intertropical Convergence Zone (ITCZ) begins at 10N134W to beyond 08N140W. Scattered moderate to strong convection is within 180 nm south of the axis between 103W and 106W, from 10N to 14N between 110W and 113W, and within 120 south of the axis between 110W and 115W. Scattered moderate isolated strong convection is within 240 nm south of the axis between 114W and 118W, and also within 120 nm north of the axis between 104W and 106W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Deep low pressure over the southwestern United States and northwest Mexico is creating a tight pressure gradient across the northern Gulf of California and Baja California Norte. Winds have increased from south to southwest in direction to near gale force, with seas to 9 ft. These winds will slowly diminish to strong winds by early Sun, with seas to 8 ft. Winds diminish further to moderate to fresh winds on Sun afternoon as the gradient slackens. Seas subside to less than 8 ft Sun night. Meanwhile, gentle to moderate winds will dominate the offshore waters W of Baja California with seas of 6-9 ft in long period NW swell. These marine conditions will persist this upcoming weekend. Seas will subside to 5-7 ft by early Sun evening. Farther south in the Gulf of Tehuantepec, mainly light to gentle winds are expected through the upcoming weekend, with seas of 4-6 ft in long period southerly swell. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Moderate to fresh NE-E winds are expected across the Gulf of Papagayo through Sat night then diminishing thereafter. Seas are forecast to be in the 4 to 6 ft range through early next week. 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 1032 mb high pressure, centered well north of the area near 45N135W, southeastward to near the Revillagigedo Islands. Low pressure, remnants of Tropical Depression One-E, is located near 13N130W with a central pressure of 1009 mb. The small cyclonic circulation of the low is clearly exposed, and will becomes ill-defined with time. Latest satellite imagery shows remaining deep convection well removed to the northeast of the cyclonic circulation. It consists of scattered moderate isolated strong convection from 13N to 14N between 129W and 130W, while scattered moderate convection is within 30 nm of 14N128W. Isolated showers and thunderstorms are seen from 13N to 15N between 130W and 131W. The pressure gradient between the aforementioned ridge and the remnant low is supporting generally moderate to locally fresh trade winds over the area to the west of 130W, with the exception strong winds within 90 nm in its NW quadrant with seas in the 8 to 10 ft range. The low is forecast to maintain its present slow west- northwest motion as it reaches near 14N131W this evening, then briefly become stationary before it tracks back to the east- southeast through Sun night as it weakens further and eventually opens up to a trough. Northwest swell producing seas of 8 to 9 ft will continue to propagate south of 32N reaching as far south as 22N by early Sun afternoon before decaying below 8 ft by Sun night. Seas will reach 8 ft south of the monsoon trough between 100W and 120W today due to the fresh southwest flow and southerly, cross- equatorial swell. Seas will subside to less than 8 ft by late Sun. Satellite imagery is revealing the existence of a broad area of deep convection made of scattered strong to scattered moderate to isolated type intensity as described above under the ITCZ/Monsoon trough section. This area of convective activity lies to the south and southeast of an upper level trough that is helping to sustain with upper level diffluence occurring to its east. Will have to watch this area of active weather for the possibility of low pressure forming there during the next 48 hours. $$ Aguirre