000 AXPZ20 KNHC 161007 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 653 UTC Fri Sep 16 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...SPECIAL FEATURES... Tropical Storm Orlene is centered near 19.9N 125.2W at 0900 UTC moving W at 10 kt. Estimated minimum central pressure is 1002 mb. Maximum sustained winds are 45 kt with gusts to 55 kt. Scattered moderate convection is seen in the SW semicircle within 120 nm of the center. Orlene is expected to continue weakening and moving W through Sun. orlene could become a tropical depression by tonight or Saturday. See latest NHC forecast/ advisory under AWIPS/WMO headers MIATCMEP1/WTPZ21 KNHC for more details. A broad and disorganized area of low pres is centered in the monsoon trough about 450 nm SW of Acapulco Mexico. This system is expected to become a tropical depression during this weekend or early next week while it moves WNW to NW at 10 mph, parallel to the coast of Mexico. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 08N77W to 13N100W to a 1007 mb low pres near 12N106W to 10N113W to 10N132W. The ITCZ continues from 10N132W to 10N140W. Scattered moderate and isolated strong convection is present from 03N to 06N between 77W and 81W and from 07N to 17N between 92W and 109W. Scattered moderate convection is found from 07N to 11N between 110W and 120W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Surface ridging reaches from 1027 mb high pres near 35N145W to near the southern tip of Baja California Sur at 22N112W. The ridge is supporting moderate to locally fresh NW to N winds along the Pacific coast of Baja California and 4 to 6 ft seas. Winds will diminish tonight through Sunday, with gentle to moderate winds prevailing W of Baja California. A surface trough over the Baja peninsula will maintain light to gentle winds over the Gulf of California. Low pres currently SW of Acapulco is still expected to develop this weekend and approach the Revillagigedo Islands early on Sunday. Even if it does not become a tropical cyclone, the potential for strong southerly winds between Revillagigedo and Cabo Corrientes and Cabo San Lucas will be present Sunday through Monday with seas to 11-13 ft. In the Gulf of Tehuantepec, N winds will pulse to between moderate and fresh during the overnight and early morning hours Sunday through Tuesday. N winds could become strong Tuesday night through early Wednesday morning. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... The monsoon trough will linger in the vicinity of 09N through Monday. Light to gentle winds are expected S of 07N through early next week. Mainly moderate SW to W winds expected over the waters S of 05N. Combined seas of 4 to 6 ft are likely across the entire area through the weekend into next week as long period SW swell continue to propagate across the equator from the southern hemisphere. Scattered showers and isolated thunderstorms are possible at night over the offshore waters. REMAINDER OF THE AREA... The ridge over the northern waters will support fresh to strong trades through the end of the week N of 11N and W of 129W. This will cause seas to build to between 8 and 9 ft from 11N to 24N W of 129W. Winds and seas will diminish this weekend as the ridge weakens and Orlene moves W. SW winds feeding into the monsoon trough are expected to increase this morning from 07N to 11N between 100W and 108W, S of the developing low pres area, then diminish in this area through Sunday as the low moves N. $$ cam