000 AXPZ20 KNHC 131556 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1555 UTC Tue Sep 13 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 500 UTC. ...SPECIAL FEATURES... Hurricane Orlene centered near 19.8N 118.7W at 13/1500 UTC or about 525 nm west-southwest of the southern tip of the Baja California Peninsula moving north-northeast at 4 kt. Estimated minimum central pressure is 975 mb. Maximum sustained wind speed is 85 kt with gusts to 105 kt. Numerous moderate and isolated strong convection is within 60 nm of the center, except within 120 nm extending around Orlene as a band in the northeast quadrant. Orlene is forecast to continue to the north with a slowing forward speed, then will drift north-northwest later today, followed by a turn to the west on Wednesday. See latest NHC forecast/advisory under AWIPS/WMO headers MIATCMEP1/WTPZ21 KNHC for more details. ...TROPICAL WAVES... A tropical wave is analyzed north of 10N along 94W moving west at around 5 to 10 kt. Scattered moderate to isolated strong convection is noted north of 10N between 90W and 96W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 10N94W to low pressure near 12N101W to low pressure near 11N108W to 10N112W.where it is discontinuous resuming at 15N123W and extending to 13N137W to 11N140W. Scattered moderate convection is within 60 nm either side of monsoon trough axis between 105W and 108W. Scattered moderate convection is noted within 90 nm north of the monsoon trough axis west of 138W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Strong southerly winds are likely ongoing over the far northern extent of the Gulf of California this morning on the eastern side of a surface trough reaching through the central Gulf region. These winds will diminish through late today as the trough and low pressure north of the area weaken. Relatively light northerly flow off the Pacific coast of Baja California Norte will increase to 10 to 15 kt through late today as high pressure builds. Meanwhile swell generated from Hurricane Orlene will impact the offshore areas of Baja California Sur although beyond 150 nm offshore and near Clarion Island through late Wednesday. Farther south, the tropical wave moving into the Gulf of Tehuantepec enhanced the overnight coastal showers and thunderstorms off coasts of Chiapas and eastern Oaxaca. This activity is starting to diminish, but additional overnight coastal showers and thunderstorms are likely off Oaxaca as the tropical wave shifts west. Light to moderate winds and modest seas prevail elsewhere and little change is expected through the next couple of days. Looking ahead, An area of low pressure is expected to form late this week or this weekend several hundred miles south or south- southwest of the southwestern coast of Mexico. Slow development of this system is possible after that time while the low moves generally west- northwestward. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Light to gentle winds are forecast to the north of 10N through tonight and south of 07N on Wednesday through Saturday, while moderate southwest to west low level flow is expected across the discussion waters generally to the south of these positions. Forecast combined seas of 4 to 6 ft across the entire area through the period primarily in long-period southwest swell. REMAINDER OF THE AREA... Except as previously mentioned in the special features section concerning Hurricane Orlene, a sub-tropical ridge is rebuilding from west to east across the northern waters. $$ CHRISTENSEN