000 AXPZ20 KNHC 301623 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Sat Jun 30 2018 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... At 1500 UTC Jun 30 newly downgraded TROPICAL DEPRESSION EMILIA was centered at 17.7N 119.2W, or about 610 nm WSW of the southern tip of the Baja California Peninsula, moving west- northwest, or 295 degrees at 10 kt. The estimated minimum central pressure is 1004 mb. The maximum sustained wind speed is 30 kt with gusts to 40 kt. Emilia has weakened overnight as it has moved into cooler waters, with scattered moderate and isolated strong convection confined to within 210 nm across the SW quadrant. Emilia is expected to continue to gradually weaken as it moves WNW and will likely degenerate to a remnant low later today or tonight. Refer to the latest NHC forecast/advisory under AWIPS/WMO headers MIATCPEP1/WTPZ31 KNHC for additional details. A 1008 mb surface low embedded along the monsoon trough is centered near 11N103W, moving WNW 12 kt. Satellite imagery shows a large and well defined cyclonic circulation associated with this low between 98W and 109W. Deep convection continues about the periphery of this circulation, with scattered moderate to strong convection noted within 300 nm across the N semicircle and 120 nm across the SW quadrant. Environmental conditions are favorable for continued improved organization and this system is likely to become a tropical cyclone during the next 48 hours. Even if the convection does not organize into persistent banding, the tightening pressure gradient will produce easterly winds near gale force north of the center tonight through Sun, with minimal gale force conditions forecast across the northeast quadrant on Sunt. This system will continue to move WNW at 10-15 kt over the next few days, with near gale force winds and high seas brushing across the far outer waters offshore the area from Acapulco to Manzanillo this afternoon and tonight. Global models suggest that this system may intensify quickly Mon and Tue and reach hurricane strength. Refer to the latest high seas forecast under AWIPS/WMO headers HSFEP2/FZPN03 KNHC for additional details on this developing gale. ...TROPICAL WAVES... A tropical wave is along 90W, moving west at 10 kt. Scattered moderate to strong convection is observed south of the monsoon trough, and ahead of the wave between 90w and 99W, and more widely scattered elsewhere to the south of the Gulf of Tehuantepec. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09.5N74W TO 08.5N90W TO LOW PRES 11N103W TO 14N108W. The ITCZ continues west from 11Nn124W to beyond 07N140W. Scattered moderate isolated strong convection is observed from 02.5n to 09.5N between 78W and 88W. Scattered moderate to strong is noted from 03.5N to 09.5N between 90W and 99W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... See the special features section for details regarding the developing low pressure system centered near 10N101W. A northwest to southeast orientated low level ridge will extend across the Pacific waters west of the Baja California Peninsula through early next week. Light to occasionally moderate winds are expected around this ridge. Gulf of California: Fresh south to southwest winds are forecast along 30N through late this morning followed by moderate winds through tonight. Light and variable winds forecast elsewhere across the gulf waters through Sun. Gulf of Tehuantepec: Variable winds at less than 15 kt are expected through Mon. Extended guidance is suggesting strong northerly winds late Wed night. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... See the special features section for details regarding the developing low pressure system centered near 10N101W. Gulf of Papagayo: Strong offshore winds have spread from the Gulf of Papagayo downstream to near 94W this morning, where seas have built 6-8 ft. Fresh to occasionally strong offshore winds will continue across and within 150 nm downstream of the Gulf of Papagayo through the middle of next week. Gentle to occasionally moderate easterly winds are forecast elsewhere north of the monsoon trough which is meandering between 08N and 10N, and gentle to moderate southerly winds are forecast south of the monsoon trough through the weekend. REMAINDER OF THE AREA... See the special features section for further details on Tropical Storm Emilia and the developing low pressure system currently near 10N101W. Elsewhere, a surface ridge extends into the area from near 32N134W to beyond 26N118W. Moderate to locally fresh northeasterly winds, and 6 to 8 ft seas, are expected to continue across the area through late Sun. Fresh to locally strong north winds, accompanied by 7 to 9 ft seas, will reach along 32N between 125W and 135W on Sun night. These conditions will propagate south to along 29.5N between 130W and 140W by early Mon, with seas of 8 to 10 ft forecast west of a line from 32N123W to 23N140W, in the wake of a weak cold front passing through the discussion area north of 30N. $$ Stripling