000 AXPZ20 KNHC 140247 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Fri Jul 14 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 0000 UTC surface analysis and satellite imagery through 0130 UTC. ...SPECIAL FEATURES... Hurricane Fernanda continues to strengthen this evening, centered near 11.0N 117.0W at 0300 UTC, or about 821 nm SSW of the southern tip of Baja California, moving W at 10 kt. Estimated minimum central pressure is 988 mb. Maximum sustained wind speed is 75 kt with gusts to 90 kt. Scattered to numerous moderate to strong convection is within 120 nm across the NE and 45 nm across the SW semicircles. Scattered moderate to strong convection is elsewhere within 150 nm NE and 90 nm SW semicircles. Fernanda is forecast to continue westward for the next few days, and gradually strengthen to a major hurricane by Sat. See latest NHC forecast/advisory under AWIPS/WMO headers MIATCMEP1/WTPZ21 for more details. ...TROPICAL WAVES... A tropical wave extends along 94-95W to across southeastern Mexico and the Gulf of Tehuantepec, moving W at 15 kt. Associated convection is described below, and continues mostly behind the wave. Afternoon scatterometer data depicted a broad weak cyclonic circulation along the monsoon trough at about 10N between 92W and 94W, with winds less than 15 kt. A tropical wave is along 102W moving W at 10 to 15 kt. Associated convection is described below. Satellite imagery suggests weak cyclonic turning in the middle levels of the atmosphere associated with this wave. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 09N75W to 10N90W to 11N111W, then resumes from 11N121W to 12.5N125W to 10.5N140W. Scattered to numerous moderate to strong convection is from 03N TO 10N east of 84W. Scattered moderate to strong convection is from 07.5N TO 13.5N between 90W and 110W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Moderate NW winds prevail offshore of Baja California this evening and are expected to remain gentle to moderate into the weekend. Winds will freshen modestly near the coast each afternoon through evening due to daytime heating through Friday night. The remnant circulation of Eugene continues to dissipate and move away from the area, leaving light and variable winds farther offshore, generally W of 117W. Swells generated by Eugene will continue to affect the W coast of Baja California and southern California during the next day or so causing zones of dangerous surf and strong rip current conditions. Seas continue to subside gradually and are expected to maintain a range of 4 to 6 ft in S to SW swell tonight through early next week. Winds are expected to become light and variable again by early next week as broad troughing sets up across the offshore waters. In the Gulf of California, mainly light and variable winds will prevail, except occasionally pulsing to moderate out of the SE in the northern Gulf each morning through noon. Seas will be 1 to 3 ft, except 3 to 4 ft near the entrance. In the Gulf of Tehuantepec, northerly winds will pulse to fresh during the nighttime hours through Saturday morning, then will be weaker each morning through Tuesday. Thereafter, winds will resume a fresh pulse each morning the remainder of the week. Elsewhere, mainly gentle variable winds and seas of 4 to 6 ft will prevail through the next several days. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... In the Gulf of Papagayo, moderate offshore nocturnal winds will pulse to fresh through Saturday morning, then will be weaker thereafter. Gentle to moderate southerly winds are expected S of the monsoon trough axis. Long period cross-equatorial southerly swell and seas 6 to 7 ft has begun to propagate through the waters W of Colombia and Ecuador, with a reinforcing pulse of swell moving across the area Friday night and reaching the Central America coast by Saturday night. REMAINDER OF THE AREA... Please see the special features section for information on Hurricane Fernanda. Post-tropical cyclone Eugene was analyzed near 26N126W as a 1012 mb low center. The center remains void of any deep convection, but moderate shallow convection is found within 120 nm from center across the NW quadrant. The remnant circulation will continue to move NW for the next couple of days before dissipation. Associated winds and seas will diminish through Friday. Otherwise, mainly moderate trades will prevail N of the convergence zone through the next several days, except increasing to fresh in the N central waters with a tight pressure gradient present offshore of central California Sunday night through early Tuesday. Seas of 4 to 7 ft outside of any tropical cyclone activity will prevail, except building to 8 to 9 ft in the N central waters when the stronger winds occur. $$ Stripling