000 AXPZ20 KNHC 010950 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Tue Jan 01 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 0600 UTC surface analysis and satellite imagery through 0845 UTC. ...SPECIAL FEATURES... ...Gale Warning Gulf of Papagayo region... Strong to gale force tradewinds across the central and western Caribbean are producing strong offshore winds across the typical Central America gap wind zones, from the Gulf of Fonseca to the Papagayo region to the Gulf of Panama tonight. The Atlantic high pressure ridge producing this strong pressure gradient across the Caribbean will build slightly westward through Wednesday and act to increase the strong gap winds across these Central American coastal areas today through Wed. Latest computer model guidance indicates that winds across the Papagayo region will increase to gale force tonight by around midnight through Wed morning before diminishing slightly, and below gale force by around noon on Wed. .INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 09N74W TO 02N79W TO 04N87W. The ITCZ continues from 04N87W TO 06N125W to beyond 06N140W. Scattered to locally numerous moderate to strong convection is noted from 03.5N to 12N W of 111W. Widely scattered moderate isolated strong convection is noted from 12N to 16N between 110W and 130W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Deep layered low pressure across the SW U.S. is sinking slowly southward tonight, with the associated surface pattern producing gentle to moderate NW to W winds across the waters of Baja California. New northwesterly swell is propagating across the waters off Baja California Norte tonight, and raising seas to the 7-10 ft range, and 4-6 ft across Baja California Sur. Seas will peak overnight then generally subside below 8 ft Tue night through Wed. Gulf of California: This same weather system across the SW U.S. has begun to produce strong northerly winds across the far north portions of the Gulf tonight, and will spread southward across the Gulf waters today as a cold front moves southward across the Gulf waters. High pressure building from the Great Basin region will support these strong NWly winds spreading down the full length of the Gulf of California today through Wed night. Strong northerly winds will spill through the mountain gaps of the Baja Peninsula to produce narrow zones of strong and gusty NE winds across the offshore Pacific waters of Baja California Tue night through late Wed night. Gulf of Tehuantepec: Strong gap winds are expected to return to Tehuantepec late tonight, before diminishing on Wed. Another cold front is expected to move across the western Gulf of Mexico Thu and reach the Bay of Campeche early Fri. Winds behind the front will funnel into the Gulf of Tehuantepec Fri morning and likely strengthen to gale force by midday Fri. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... As mentioned above, strong gap winds across the Papagayo region will increase to minimal gale force tonight through Wed morning. Moderate to fresh N winds are expected across the Gulf of Panama through Thu, pulsing to strong during the overnight hours. Elsewhere, gentle to moderate NE winds will prevail N of 08N, while gentle to moderate southerly winds are expected S of 08N. REMAINDER OF THE AREA... The pressure gradient between strong high pressure N of the area and lower pressure in the vicinity of the ITCZ is maintaining a broad area of fresh to strong tradewinds N of the ITCZ to near 21N and W of 110W. This area of high pressure will remain in place N of the area helping to maintain this broad area of fresh to strong trades. Long period NW swell is merging with this tradewind swell to produce seas of 8 to 13 ft over much of the area north of the ITCZ west of 120W. Global models continue to indicate a cold-core upper low will dig southward into the base of a mid/upper level trough between 125W and 145W today through Fri. This will support the development of a sharp surface trough or even weak low pressure along the ITCZ between 120W and 130W by Wed. The resultant tightened pressure gradient will enhance trade winds north of the ITCZ and west of 120W, with near gale conditions possible developing north of the surface trough or low to near 15N. $$ Stripling