000 AXPZ20 KNHC 300407 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 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 0000 UTC surface analysis and satellite imagery through 0345 UTC. ...SPECIAL FEATURES... At 29/2100 UTC Tropical Storm Emilia was centered at 16.8N 117.8W, or 665 miles SW of the southern tip of the Baja California Peninsula moving west-northwest at 9 kt. The estimated minimum central pressure is 1000 mb. The maximum sustained wind speed is 40 kt with gusts to 50 kt. Easterly shear continues with numerous strong convection observed within 210 nm over the west semicircle of the center. Emily is forecast to move over cooler surface waters and gradually weaken to a tropical depression on Sun. Refer to the latest NHC forecast/advisory under AWIPS/WMO headers MIATCPEP1/WTPZ31 KNHC for additional details. A 1009 mb surface low is centered near 10N100W, drifting westward. Scattered moderate and isolated strong convection is observed to the north of the system within 180 nm either side of a line from 14N95W to 10N108W. Environmental conditions are favorable for continued development with a high chance for this system to become a tropical cyclone during the next 48 hours. Even if convection does not organize, the tightening pressure gradient will produce easterly winds near gale force north of the center on Sat, with minimal gale force conditions forecast within 210 nm over the northeast quadrant by late Sun. Fresh to strong east winds are forecast south of 13N between 95W and 105W through early Sun. Strong to near gale force easterly winds are forecast south of 15N between 100W and 108W on Sun, and south of 17N between 106W and 110W on Sun night. Fresh winds will develop across the waters well southwest of the south tip of the Baja Peninsula early next week. 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 analyzed north of 07N along 87W and is moving west at 12 kt. Scattered moderate and isolated strong convection is observed within 75 nm of 11N86W and 05N87W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends west across off the Pacific coast of Colombia at 08N78W through a tropical wave along 87W to the tropical low pressure at 10N100W, then resumes southwest of tropical cyclone Emilia at 14N122W to 09N135W where scatterometer winds indicate a transition to an ITCZ which continues west to beyond 08N140W. Aside from the convection associated with T.S. Emilia and the tropical wave along 87w and the surface low at 10N100W, Scattered moderate isolated strong convection is observed within 75 nm either side of a line from 07N82W to 11N88W, and within 120 nm either side of a line from 04N86W to 07N96W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... See the special features section for details regarding the developing low pressure system centered near 10N100W. 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 Sat morning followed by moderate winds through Sat night. Light and variable winds forecast elsewhere across the gulf waters through Sun. Gulf of Tehuantepec: Extended guidance is suggest 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 10N100W. Gulf of Papagayo: Fresh to occasionally strong offshore winds will occur 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, 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 10N100W. Elsewhere, a surface ridge extends into the area from near 32N136W 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 behind a weak cold front passing through the discussion area north of 30N. $$ Nelson