000 AXPZ20 KNHC 100300 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 300 UTC Sat Mar 10 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 0000 UTC surface analysis and satellite imagery through 0230 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 06N78W to 05N88W. The ITCZ axis continues from 05N88W to 02N110W to 04N125W to 07N140W. Scattered moderate convection is from 10N to 13N between 136W and 139W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... High pressure of 1021 mb centered near 27N121W ridges SE across the open waters W of the Baja California peninsula. Mainly light to moderate NW-N winds prevail beneath this ridge, except moderate to locally fresh winds adjacent to the Baja California peninsula. These conditions will prevail through Sat. Winds will increase to between 15 and 20 kt Sun through Tue as the high gradually builds, with the high then weakening by mid-week as a decaying cold front approaches. Winds near Cabo Corrientes could become locally strong on Sun. Gulf of California: Light to gentle winds are expected across the northern Gulf through Sat, with mainly gentle to moderate winds prevailing across the central and southern waters. Winds will increase to 10-15 kt across the northern Gulf Sun through early next week in response to building high pres just NW of the offshore zones. Winds will become fresh to locally strong across the central and southern waters Sun night and Mon. The pressure gradient across the region will weaken Tue through Wed allowing for winds to diminish to gentle to moderate across the Gulf of California. Gulf of Tehuantepec: Light to moderate onshore winds will prevail through the weekend. Model guidance suggests another northerly gap wind event commencing late Sun night and early Mon as expansive high pressure builds southward over the western Gulf of Mexico behind the next cold front. Winds will rapidly increase to gale force Mon afternoon or evening, and approaching strong gale force Mon night into Tue morning. Gale force winds may diminish by the end of the week. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... The Fuego Volcano located in Guatemala near 14.5N90.9W continues to intermittently vent light amounts of smoke and ash. Any significant ash emissions that do occur will likely remain over land to the west of the summit during the next 12 to 24 hours. High pressure ridging SE over the Caribbean is generating fresh to strong offshore gap winds over the Gulf of Papagayo, but the ridge has weakened. Strong winds will continue over the Gulf of Papagayo through Sun morning, but the areal coverage will be minimal. Winds will spike to 30 kt tonight into early Sat morning, with seas building to around 8 ft. The ridging will continue to weaken by the end of the weekend into early next week, and winds will only pulse to moderate to fresh Sun night through mid-week. Over the Gulf of Panama, moderate N winds will pulse to fresh during the overnight and early morning hours through Sat morning. Seas are expected to be 5-6 ft as N wind waves mix with moderate cross-equatorial SW swell. Elsewhere, expect gentle to moderate winds and 4-7 ft seas to prevail during the next couple of days. REMAINDER OF THE AREA... A rather complex set of surface troughs and broad low pressure is present across the NW portion and N central waters. Deep tropical moisture extends from across the Hawaiian Islands into the discussion waters, with scattered moderate and isolated strong convection within an area bounded by 30N135W to 30N124W to 19N133W to 14N140W to 25N140W to 30N135W. Model guidance indicates fresh to strong winds embedded in this area centered near 28.5N130W through Sat morning, with seas to 8 ft. The next cold front will breach 30N140W from the NW by Sun afternoon. An area of fresh to strong SW winds will precede the front, as well as follow it, diminishing by Mon night. Large NW swell will also accompany the boundary reaching up to 14-16 ft by Mon evening. The front will weaken as it moves across the NW portion, then a weaker cold front will introduce a round of reinforcing NW swell Tue night through Wed night. Moderate to locally fresh trades combined with decaying NW swell is supporting combined seas of 7-9 ft across the W central waters to the N of the convergence zone. The pressure gradient will weaken this weekend allowing for the seas to subside to less than 8 ft. $$ Lewitsky