000 AXPZ20 KNHC 102152 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1925 UTC Wed Jan 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 1800 UTC surface analysis and satellite imagery through 2030 UTC. ...SPECIAL FEATURE... Gulf of Tehuantepec Gale Warning: Winds over the Gulf are light and variable with seas running between 2 and 4 ft. The current lull in the action will be be brief. A very strong cold front blasting southward through the western Gulf of Mexico Thu night and Fri morning will set the stage for a long and robust gap wind event projected to begin abruptly over the Gulf around dawn Fri morning as winds quickly increase to gale force. Once winds increase to gale force, they are not expected to fall below gale force until at least Wed night. This event is forecasted to peak at storm force on Sun. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 09N83W to 08N86W to 06N89W to 05N93W. The ITCZ continues from 05N93W to 07N122W to beyond 08N140W. Scattered moderate convection is present from 05N to 08N between 81W and 87W and from 12N to 16N between 129W and 138W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A cold front moving SE across Baja California Sur crosses the Gulf of California from 27N110W to 25.5N111W. The front continues SW across the Baja Peninsula to 24.5N112W, across the Pacific to 21.5N115.5W, then continues as a weakening cold front to 17N124W. Winds on the Pacific side of the Baja Peninsula are moderate to fresh on either side of the front. Large seas of 12 to 14 ft are located west of the front to 124W and north of 26.5N. The front will continue advancing SE across the remainder of Baja California Sur and the southern Gulf of California this evening, then dissipate tonight. Winds in the vicinity of the front will subside to moderate by dawn. The large NW swell will gradually decay off Baja California through Thu. Seas in the vicinity of the Revillagigedo Islands will subside below 8 ft Fri morning. Strong high pressure building over the U.S. Great Basin will generate strong NW winds over the southern two thirds of the Gulf of California Thu evening through Fri night, with seas peaking close to 8 ft around dawn on Fri morning near 26N. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... A weak pressure gradient over central America is maintaining moderate to fresh gap winds over the Gulf of Papagayo. Strong winds are expected to redevelop there Sat morning as high pres builds over the western Caribbean. Winds could reach gale force on Mon morning. The area of seas developing S of the Gulf of Papagayo will merge with the larger area of seas already present south of Tehuantepec on Sun. Elsewhere, light to moderate SW winds will persist S of Costa Rica and Panama. Seas will remain generally between 3 and 5 ft. N winds over the Gulf of Panama could become fresh by Mon morning. REMAINDER OF THE AREA... As noted above, a cold front extends across the forecast waters from 24.5N112W to 21.5N115.5W, then continues as a weakening cold front to 17N124W. The pressure gradient between 1029 mb high pres centered near 31N133W and lower pressure in the vicinity of the ITCZ will generally support fresh to strong NE winds from 15N to 18N between 122W and 137W this evening through Thu morning. The areal coverage of 8 ft seas over the forecast waters will peak on Thu as the area of seas encompasses virtually all of the waters W of 110W and N of 10N. This area of seas will slowly decay on Fri and Sat. A cold front approaching 30N140W Sun will generate more large long period NW swell that could cause seas to build to as high as 21 ft in the far northwest waters near 30N140W by Sun evening. $$ CAM