000 AXPZ20 KNHC 031540 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Wed Aug 3 2016 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 1500 UTC. ...SPECIAL FEATURES... Tropical Storm Ivette centered near 14.6N 120.4W at 1500 UTC, moving WNW or 285 degrees at 15 kt. Estimated minimum central pressure 1004 mb. Maximum sustained winds 40 kt with gusts to 50 kt. Satellite imagery indicates Ivette is becoming better organized, with scattered moderate to strong convection within 120 nm of 14N121W. Microwave data shows the low level center displaced northeast of the deepest convection due to moderate vertical shear. Ivette is forecast to continue moving W to WNW across warm waters of the open ocean during the next 48 hours under favorable atmospheric conditions, and is expected to strengthen and reach hurricane intensity within 48 hours. See latest NHC forecast/advisory under AWIPS/WMO headers MIATCMEP5/WTPZ25 KNHC for more details. Tropical Storm Howard centered near 21.1N 133.8W, moving WNW or 295 degrees at 1 kt. Estimated minimum central pressure 1006 mb. Maximum sustained winds are 35 kt with gusts to 45 kt. Howard has lost all of its deep convection as it moves over cooler waters, and is expected to transition to a post-tropical remnant low during the next 12-24 hours as it continues moving WNW. Seas associated with this system will shift west of 140W by Friday. See latest NHC forecast/advisory under AWIPS/WMO headers MIATCMEP4/WTPZ24 KNHC for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A discontinuous monsoon trough extends from 10N102W to 12N113W, then continues from 11N122W to 08N132W. The ITCZ extends W from 12N136W to beyond 12N140W. Scattered moderate convection from 09N to 12N between 105W-110W. Scattered moderate isolated strong convection from 08N-13N between 83W-93W. ...DISCUSSION... N of 15N E of 120W: Weak surface troughing will persist along the Baja California peninsula through Friday. Light to moderate S winds will prevail across the north central Gulf of California the next few days. In the Gulf of Tehuantepec, fresh N winds will continue across the area through Thu, and pulse to 25 kt overnight into early morning hours. Seas will build to 7-9 ft in the morning...then subside to 5-7 ft each afternoon. Heavy rain associated with widespread showers and thunderstorms occurring ahead of Earl in the western Caribbean will shift westward across central America into the Tehuantepec region and southern Mexico Thu and Fri. Elsewhere, a weak surface ridge extends into the area from the NW. This ridge will support gentle to locally moderate NW winds across the open Pacific waters offshore of Baja California, with seas 4-6 ft range in mixed N and SW southern hemisphere swell. S of 15N E of 120W: East of 100W, light to moderate monsoonal winds are expected through Thu as Earl moves across central America. Widespread showers and a few thunderstorms are occurring over Central America well ahead of Earl. This very active weather is expected to continue across the tropical eastern Pacific and central America during the next couple of days and will generally shift westward with the tropical cyclone. Torrential rainfall and flash flooding will be possible during this time. See the latest bulletins and advisories from your local weather agencies. Long-period cross-equatorial SW swell will produce 4-7 ft seas across the region the next few days. W of 120W: TS Ivette is moving across 120W and TS Howard will weaken and exit the forecast waters. See the special features section for details. Ridging extending into the region from NW of the area is maintaining moderate to occasionally fresh NE to E winds. Fresh to strong NE winds offshore of California will generate fresh NNE swell that will move into the northern waters. Seas to 8 ft will propagate southward toward 30N at times through Fri. $$ Mundell