000 AXPZ20 KNHC 140406 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Sun Jan 14 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 0245 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Storm Warning: Gale to minimal storm force northerly winds of 35 to 50 kt are blowing across the gulf tonight, extending downwind to near 13.5N96W, with maximum seas of around 20 ft. The storm force conditions should end around sunrise on Sun, but strong gale conditions will persist through the middle of the week ending around sunset on Thu, with winds forecast at 20 kt or less on Fri afternoon. The resultant plume of NE swells, in the form of 8 to 11 ft seas, will propagate S and SW, crossing the equator between 93W and 109W on Mon night, while reaching far W as 10N125W by late Mon. Gulf of Papagayo Gale Warning: Strong NE winds currently observed across the Gulf of Papagayo will continue to spread SW and reach as far SW as 07N93W by sunrise Sun, when gale force winds will commence from the gulf to near 09N87.5W and continue until mid afternoon, before diminishing slightly, then will increase to gale force again Sun night through Mon morning. Seas will build to 11 ft during this time, and continue through Mon. Strong high pressure across the U.S. behind a W Caribbean cold front is the force behind these winds, and will begin to weaken Tue and Tue night, with winds and seas subsiding modestly across the Papagayo region. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends WSW from the Pacific coast of Colombia W across Panama to the Pacific coast near 08.5N83W TO 06.5N97.5W. Afternoon scatterometer winds indicated a transition to ITCZ at 06.5N97.5W to a 1011 mb surface low near 07N112W to 09.5N129W to beyond 07.5N140W. Scattered moderate to strong convection is observed from 04N to 08N between 77W and 90W. Scattered to locally numerous moderate to strong convection is observed from 06N to 09.5N between 106W and 116W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... W of the Baja California Peninsula: A gentle variable breeze is forecast around a weak N to S orientated trough along 114W, with the possibility of weak surface low forming briefly. The trough will shift W reaching along 119W on Sun, then move back E again on Sun night into Mon and then gradually lose identity along 115W as as ridge axis builds E into the area along 23N117W to 16N105W on Mon night. Seas will subside to 4 to 7 ft overnight and continue through midday Sun. The leading edge of large NW swell will arrive near 30N120W early Mon, with seas of 8 to 13 ft expected W of Baja on Mon night primarily due to 20 to 23 second long-period NW swell. Gulf of California: Fresh to locally strong NW winds, and 3 to 5 ft seas are currently observed across the far northern gulf waters. These winds should diminish by late this evening. Moderate NW breezes will continue elsewhere through late Tue before diminishing to a light NW breeze. See special feature section above for information about the storm warning and gale conditions across the Gulf of Tehuantepec. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... See special feature section above for information about the gale warning for the Gulf of Papagayo. Gulf of Fonseca: Strong N to NE winds behind a W Caribbean cold front will surge across Central America and through the gaps across the Pacific waters to the N of 11N and E of 92W, including the Gulf of Fonseca overnight. The NE swell from these gap winds, and large E swells from the Gulf of Papagayo event further to the S, will merge on Sun with N swell propagating S from the Gulf of Tehuantepec, resulting in 7 to 11 ft seas across the offshore waters from roughly 04N to 14N W of 87W. These seas will continue through Tue before subsiding from the E. Fresh N winds across the Gulf of Panama will continue through sunrise on Mon. Elsewhere, light to moderate SW winds will persist S of Costa Rica and Panama through Sat with seas generally between 3 and 5 ft. REMAINDER OF THE AREA... Strong to near gale force southerly winds are observed across the waters from 29N to 32W W of 137W ahead of a cold front that will reach 32N140W overnight. Although the front will nearly stall from near 32N125W to 27N140W on Tue, large 10 to 16 ft seas primarily due to long period 17 to 22 second NW swell, will propagate SE across the discussion area Mon through Wed. A secondary cold front will reach 32N140W on Sun night and help to maintain seas 15-18 ft along 32N. $$ Stripling