000 AXPZ20 KNHC 121552 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Wed Jul 12 2017 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 1530 UTC. ...SPECIAL FEATURES... Recently upgraded Tropical Storm Fernanda is centered near 12.0N 111.5W at 12/1500 UTC or about 660 nm south of the southern tip of Baja California moving westward or 270 degrees at 9 kt. Estimated minimum central pressure is 1006 mb. Maximum sustained wind speed has increased to 35 kt with gusts to 45 kt. First visible satellite images show that cyclone is acquiring new banding features, and deep convection is increasing near the system center. This convection consists of the strong type intensity within 45 nm south and 60 nm southwest of the the center. Scattered moderate isolated strong convection is elsewhere within 90 nm of the center in the southwest quadrants, and also from 08N to 10N between 111W and 113W, within 30 nm of 10N112W and of 14N111W. Scattered moderate convection is within 60 nm of the center in the northwest quadrants, and within 30 nm either side of a line from 09.5N113W to 11N114W. The cyclone is forecast to continue to intensify, and is forecast to reach hurricane intensity by early Friday near 11.7N 118.7W with maximum sustained winds of 65 kt gusts to 80 kt and continue to strengthen through Saturday as it moves in a general westward track. See the latest NHC Forecast/Advisory under AWIPS/WMO headers MIATCMEP1/WTPZ21 KNHC for more details. Recently downgraded Tropical Depression Eugene is centered near 23.6N 121.8W at 12/1500 UTC or about 440 nm west-southwest of Punta Eugenia Mexico moving northwestward or 320 degrees at 9 kt. Estimated minimum central pressure is 1006 mb. Maximum sustained wind speed is 30 kt with gusts to 40 kt. latest satellite imagery shows Eugene continuing to weaken as noted in its diminishing convective activity and decoupling cloud pattern. Only scattered moderate convection remains to the northern of the center from 24N to 25N between 120W and 121W. Otherwise, the system consists of large swirl of broken to overcast low and mid clouds from 20N to 27N between 118W and 127W. Scattered to widely showers are possible with these clouds. The depression is forecast to continue to weaken, becoming a post-tropical remnant low by early on Thursday as it moves in a general northwest direction across increasingly cooler waters, and into a more stable environment. See the latest NHC Forecast/Advisory under AWIPS/WMO headers MIATCMEP5/WTPZ25 KNHC for more details. ...TROPICAL WAVES... Tropical wave axis is along 97W north of 08N moving westward at 10-15 kt. Scattered moderate isolated strong convection is seen within 180 nm either side of the axis from 06N to 10N, and within 180 nm east of the wave from 13N to 16N. Scattered moderate convection is within 30 nm of 14N97W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The Monsoon Trough axis extends from 09N79W to 08N94W to 09N107W where it briefly ends. It resumes at 13N117W to 10N134W where scatterometer data indicates the ITCZ begins and extends to 10N134W to 09N140W. Scattered moderate to strong convection is occurring within 180 nm south of the axis between 100W-102W, and within 120 nm south of the axis between 102W-105W. Scattered moderate isolated strong convection is within 60 nm south of the axis between 92W-94W, and also within 60 nm south of the axis between 124W-131W and within 60 nm south of the axis between 135W-138W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Higher winds and large seas associated with Tropical Depression Eugene will remain to the west of the Baja California offshore zones through this evening. Swell generated by the tropical cyclone will maintain seas ranging from 6 to 9 ft in the offshore waters zones north of Cabo San Lazaro through late tonight as Eugene continues to weaken. The pressure gradient between ridging to the west of Baja California Norte, and troughing across the Baja California peninsula is supporting gentle to moderate southerly flow across the Gulf of California, which is expected to persist through much of this week. Pulses of fresh winds are possible across the Gulf of Tehuantepec each night through Sunday, briefly building seas to 6 to 7 ft in the morning. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate to fresh nocturnal winds are expected across the Gulf of Papagayo through Friday night, with the strongest push expected Thu night into early Friday with seas to 8 ft at that time. Gentle to moderate southerly winds are expected south of the monsoon trough axis. Long period cross-equatorial southerly swell and seas 6 to 7 ft are forecast west of Colombia and Ecuador beginning on Thursday. REMAINDER OF THE AREA... The remnant low of Tropical Storm Eugene is forecast to gradually dissipate over the north central waters Friday through Saturday as stronger high pressure builds southeastward across the northwest and north-central waters. Elsewhere outside conditions associated with tropical cyclone Fernanda, the pressure gradient between the ridging over the northwest and central waters will allow for moderate to occasional fresh trades to prevail north of the ITCZ, while gentle to moderate southerly winds will occur to the south of the ITCZ. Seas will be generally 5 to 7 ft. Tropical Storm Fernanda is forecast to track in a general westward direction through the next couple of days. It is forecast to intensify to a hurricane early on Friday. This will impact winds and seas over the south-central waters as the gradient tightens on the periphery of the cyclone. Otherwise little change is expected in the forecast waters S of 20N through Friday. $$ Aguirre