000 AXPZ20 KNHC 050416 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Sat Jan 5 2019 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 0300 UTC. ...SPECIAL FEATURES... ...GALE WARNING... A cold front moving across the southern Gulf of Mexico is supporting minimal gale force northerly winds across the Gulf of Tehuantepec north of 14.5N. These winds will continue through Sat morning, then diminish to 20-30 kt throughout the day Sat, then increase to minimal gale force overnight Sat. Winds will then diminish below gale force by sunrise Sun and then remain strong through Tue. For further details please see the High Seas Forecast issued by the National Weather Service under WMO/AWIPS headers FZPN03 KNHC/HSFEP2. .INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 08.5N85W TO 05.5N89W. The ITCZ extends from 04.5N91W TO 10N120W TO 05.5N126W TO 07N133W to beyond 06N140W. Scattered to numerous moderate to strong convection is within 240 nm across the N semicircle of low pres near 14N125.5W. Widely scattered to scattered moderate isolated strong convection is from 06N to 21N between 110W and 133W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Weak high pressure centered near 29N121W extends a ridge SE to southern Baja supporting light to gentle northerly winds across the offshore waters of Baja California, with seas of 4-6 ft in fading NW swell. A low pressure center currently near 14N125.5W will track N-NE through Sat night, when it will dissipate into an elongated trough from near Cabo San Lucas in Baja California Sur to 20N120W. This will coincide with the arrival of a weakening cold front into Baja California Norte Sun morning. Associated high pressure behind the front will build eastward into the offshore waters Sun through Mon to produce fresh northerly winds across the waters. NW swell associated with the dissipating cold front will bring seas of 8-11 ft into the northern waters early Sun morning spread SE into the remaining waters through Mon. Gulf of California: N to NW winds have continued to slowly subside across the Gulf today, and are presently 15-20 kt across the gulf this evening. These winds will continue to slowly diminish through Sat night, ahead of the approaching cold front. Moderate southerly winds will occur briefly Sat night and early Sun morning across north portions just ahead of the front, then become variable less than 15 kt behind the front Sun and Sun night, while moderate NW flow develops across the remainder of the Gulf waters. Gulf of Tehuantepec: Strong to minimal gale force northerly winds will prevail across the Gulf waters and downstream to around 13N through the weekend, as mentioned above. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Strong NE to E winds are expected across and downstream of the Gulf of Papagayo through Tue. Moderate to fresh offshore gap winds are expected in the Gulf of Panama through Tue, briefly increasing to strong on Sun. Elsewhere, gentle to moderate southerly winds are expected S of 08N. REMAINDER OF THE AREA... The pressure gradient between high pressure near 29N121W and lower pressure in the vicinity of the ITCZ and complex low pressure near 14N125.5W is maintaining a zone of fresh to strong tradewinds N of the ITCZ to about 22N between 110W and 136W. This high pressure will begin to shift NE tonight ahead of an approaching cold front and gradually reduce the areal extent of these fresh to strong winds. A cold front over the NW portion of the discussion area will move eastward through the weekend, and cross 120W Sat evening as it weakens. Long period NW swell generated behind the front is merging with this tradewind swell to produce seas of 8 to 11 ft over much of the area north of the ITCZ west of 120W. Seas will increase behind the front as large NW swell raises seas to 10-14 ft to the N of 23N through Sun. $$ Stripling