000 AXPZ20 KNHC 281543 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1321 UTC Sun Apr 28 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 1200 UTC surface analysis and satellite imagery through 1520 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A trough extends from just SW of Costa Rica near 10N84W to 08N91W. The ITCZ continues from 06N100W to 05N119W, then resumes from 05N124W to beyond the discussion area near 03N140W. Scattered moderate and isolated strong convection is seen from 04N to 08N between 130W and 140W. A surface trough that splits the ITCZ extends from 05N121W to 11N115W. Scattered moderate and isolated strong convection is present within 60 nm of the trough axis. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A ridge of high pressure extends SE from 32N139W to near the Revillagigedo Islands. The ridge is weakened by a trough that extends from 30N126W to 27N130W to 24N132W. The pressure gradient on the eastern periphery of the ridge is maintaining gentle to moderate NW to N winds over the forecast waters. Seas are in the 4 to 6 ft range. With the exception of winds briefly becoming fresh along and just offshore the central part of the Baja California Peninsula during the afternoons and at night, expect near steady state conditions through Thu night. A new set of N swell will propagate S of 32N Mon, then affect the offshore waters N of 27N through Tue night. This will cause seas in this area to build about a foot higher, then seas will subside back to the current 4 to 6 foot range Thu. Gulf of California: Fresh SW winds over the northern Gulf of California will become strong Mon night and Tue as a weakening trough approaches. Winds will then diminish to fresh around midday Tue then become generally light to gentle S to SW winds Tue afternoon through Thu night. Seas over the northern part of the Gulf are presently 3 ft or less, but will build to 5 to 7 ft on Mon, then subside to 2 to 4 ft on Tue as winds diminish. Gulf of Tehuantepec: Light to moderate onshore winds and seas ranging between 4 and 6 ft are expected for the Gulf of Tehuantepec through Thu night. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Fresh NE to E winds over the Gulf of Papagayo region will become strong tonight through Thu night. Gulf of Panama: Fresh N winds over the Gulf of Panama will become light to moderate tonight. Seas in this area will be maintained in the 3 to 5 ft range as a result of the long-period S to SW swell originating from the Southern Hemisphere. Satellite-derive sea height data from around 03Z this morning indicate combined seas between Ecuador and the Galapagos Islands range between 5 and 7 ft in S to SW swell. The aforementioned long period S to SW swell will maintain combined seas near current heights through Wed, then seas will subside slightly Wed night through Thu night. Visible GOES-16 satellite images received this morning clearly depicted a widespread area of smoke and haze, some of it dense, along and adjacent to the coast of Central America and the coast of SE Mexico, including the Gulf of Tehuantepec region. The imagery revealed that the smoke and haze had spread SW as far as 10N100W. This area closely correlates with the smoke guidance issued by NOAA/NESDIS. Ongoing agricultural burning, as normally carried on during this time of year in SE Mexico and in Central America is generating the smoke and haze. Latest surface based observations highlight reduced visibility of 2 to 6 nm. The smoke could persist over the region for at least several days if burning continues while light to moderate low-level winds continue across this region. REMAINDER OF THE AREA... Moderate to fresh NE to E trades are observed over the waters from about 06N to 17N and W of 110W. NW and SW swell will help maintain combined seas in the range of 6 to 8 ft. Rather weak high pressure ridging over the northern waters will generally maintain moderate trades across the trade wind belt through early next week, with little change in combined seas expected. A new batch of N swell will cross 32N and between 124W and 132W during Mon afternoon, then propagate south to near 28N between 121W and 133W by late Mon night, with associated wave heights in the range of 7 to 9 ft. Cross-equatorial SW swell will propagate NE through much of the forecast area east of 120W through Mon night, then Tue through Thu. Combined seas of 8 ft or higher will generally be confined to the waters south of the 02S and west of 100W. Wave model guidance is remains consistent in calling for a more robust Southern Hemisphere swell event that will arrive on the Equator by Thu night. A large portion of the discussion area S of 10N and W of 110W could experience seas between 8 and 9 ft by Fri night. $$ CAM