000 AXPZ20 KNHC 172145 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Sat Mar 17 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 1800 UTC surface analysis and satellite imagery through 2145 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough is analyzed from the Pacific coast of Colombia at 04N77W to 06N90W to 06N108W where scatterometer winds indicate an ITCZ develops, and continues W to beyond 07N140W. Scattered moderate isolated strong convection is noted within 120 nm either side of a line from 08N83W to 02N92W, and within 90 nm either side of a line from 06N99W to 06N111W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A weakening cold front will pass through the open Pacific waters north of 27N this evening accompanied by a moderate southwest to west to northwest windshift. A north to south ridge will develop will develop in the wake of the front with it's axis from 30N120W to 20N110W to 12N95W on Sun. The ridge will shift slightly southwest on Mon and Tue. Fresh to locally strong northerly winds will set up south of 25N and east of the ridge briefly on Sun with the pressure gradient then relaxing some on Mon. Light to gentle northerly winds and 2 to 4 ft seas are then expected through the middle of next week. Gulf of California: A strong SW breeze is developing along 30N ahead of a cold front that will move through the northern gulf waters tonight, followed by strong northwest winds that should diminish on Sun morning. Moderate northwest flow is forecast across the entire gulf waters on Sun, increasing to a fresh breeze on Sun night, with locally strong northwest winds possible across the southern gulf waters late Mon through late Tue. Seas may build to 6 ft in the longer fetch waters. Fresh to locally strong northwest to north flow expected across the open Pacific waters from 18N to 23N east of 110W on Sun through Mon night with seas building to 8 ft. Gulf of Tehuantepec: Strong north flow will surge through the gulf waters on Tue night, increasing to minimal gale force around sunrise on Wed. Gale conditions of 30 to 40 kt are then expected to continue through late Thu night, with seas building to 15 ft downstream near 14.5N95.5W on Wed night. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Fresh to locally strong NE nocturnal winds expected tonight and again on Sun night with seas building to 7 ft downstream. Gulf of Panama: Fresh northerly winds are expected tonight and again on Sun night. Elsewhere, gentle to moderate offshore flow will prevail N of 08N while light to gentle SW winds are forecast S of 08N. REMAINDER OF THE AREA... As a cold front approaches 32N140W tonight strong southerly flow will develop across the Pacific waters from 25N to 32N west of 136W. The front will reach from 32N137W to 26N140W on Sun night, with strong southerly flow continuing north of 25N within about 270 nm east of the front. By then a secondary cold front will reach 140W, accompanied by a strong to near gale force wind shift north of 28N along the front, with seas building to 18 ft in northwest swell west of the front which should reach a position from 32N137W to 24N140W on Tue. $$ Nelson