000 AXPZ20 KNHC 242203 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2045 UTC Thu Jan 24 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 1800 UTC surface analysis and satellite imagery through 2145 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: The pressure gradient over SE Mexico has begun to slacken as high pressure ridging S over the Gulf from Louisiana slowly shifts E. However, high pres moving SE from the central plains will reinforce the ridge over the Gulf and allow NE to N gale force winds to pulse over the Gulf of Tehuantepec in conjunction with nocturnal drainage flow through Sat morning. Thereafter, the ridge will shift over the SE United States. Seas currently in the 9-14 ft range will gradually taper off through Sat, then will subside more rapidly as the current event shuts down. The area of 8 to 10 ft seas generated by this event will spread well to the S and SW of the Gulf as far as 10N100W tonight and Fri, then subside. Another strong cold front will be entering the Gulf of Mexico on Sunday. Gales will be possible over the basin again by Sun night. Please read the latest High Seas Forecast issued by the National Hurricane Center under AWIPS/WMO headers FZPN03 KNHC/HSFEP2 or at website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for further details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends SW from 1007 mb low pressure centered over northwest Colombia near 10N76W to 04N81W to 04N95W. The ITCZ continues from to 04N95W to 04N103W to 06N109W, then resumes from 06N114W to 09N134W. Scattered moderate convection is occurring N of the ITCZ within 210 nm W of 124W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gulf of California: Fresh to strong NW winds are occurring almost all of the basin. High pressure over the Great Basin will remain strong through Sat night and maintain the pressure gradient over the Gulf of California. Seas associated with these winds will peak around 8 ft. Elsewhere, high pressure to the N and NW of the area is supporting moderate to fresh northerly winds west of the Baja California peninsula. Winds will diminish across this area Fri night and Sat morning as the high weakens and shifts north. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Fresh to strong NE winds will continue pulsing across the Gulf of Papagayo through Sun afternoon. Seas in this area will peak around 8 ft on Fri morning. Gulf of Panama: Fresh N to NE winds will pulse over the Gulf will occur mainly at night and into the early afternoon through Sat. Winds could become locally strong Fri night. REMAINDER OF THE AREA... Broad 1034 mb high pressure centered well N of the area near 39N133W ridges across the forecast waters north of 10N. A surface trough curves NE from 04N138W to 12N136W. This trough interrupts the ITCZ. The surface trough is receiving strong upper-level support from a mid to upper-level trough that extends SSW from low pres near 31N137W to 09N144W. The pressure gradient between the ridge and the surface trough is generating fresh to locally strong trades from about 11N to 17N and between 129W and 138W and associated seas of 9 to 11 ft. Model guidance suggests the strong dynamics E of the upper-level low could possibly spin up a surface low along the trough near 12N on Fri. The resultant gradient could bring strong NE to E winds and seas as high as 10 to 14 ft from 15N to 23N between 125W and 138W by early on Sat. An extensive area of seas 8 to 11 ft in mixed NE and NW swell will cover the waters to the west of a line from 32N125W to 18N122W to 14N122W to 09N130W and to 03N140W by early on Sat. $$ CAM