834 AXPZ20 KNHC 252159 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2159 UTC Tue Jun 25 2019 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 1800 UTC surface analysis and satellite imagery through 2100 UTC. ...SPECIAL FEATURES... Tropical Depression One-E centered near 15.2N 105.7W at 25/2100 UTC moving WNW at 13 kt. Estimated minimum central pressure is 1007 mb. Maximum sustained wind speed is 25 kt with gusts to 35 kt. T.D. One-E may intensify slightly to a minimal tropical storm as it moves WNW of the coast of Mexico, then diminish thereafter as it continues to the Revillagigedo Islands. Scattered moderate to strong convection is evident within 90 nm of the center of the developing depression. See latest NHC forecast/advisory under AWIPS/WMO headers MIATCMEP1/WTPZ21 KNHC for more details. ...TROPICAL WAVES... A tropical wave entering the eastern Pacific from the Caribbean has an axis extending N from 05N83W into Costa Rica, moving W around 20 kt. Scattered moderate convection is seen within 90 nm of 06N78W. A weak tropical wave with an axis along 97W from 04N to 11N is moving westward around 15 kt. Scattered moderate convection is located near its axis. A tropical wave has an axis along 113W from 04N and 11N and is moving W between 15 and 20 kt. Minimal convection is evident where the tropical wave intersects the monsoon trough. A tropical wave has an axis along 124W from 03N to 15N, moving westward around 10 kt. Despite being in an area of deep layer moisture, no significant convection is evident near the wave, as this is in an area of mid to upper northerly subsidence. Scattered convection is active however just west of the tropical wave along the monsoon trough. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 08N83W to T.D. One-E to 11N125W. The ITCZ continues from 11N125W to beyond 16N140W. Scattered moderate convection is noted within 90 nm north of the monsoon trough between 85W and 90W. Scattered moderate convection within 120 nm south of the ITCZ between 125W and 135W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... See the Special Features section above for details regarding the gradual development of a low pressure system a few hundred nm SW of Acapulco. This system has a high chance of developing into a tropical cyclone during the next couple of days. A ridge axis extends southeast from 1022 mb high pressure centered well to the northwest of the area near 34N139W to near the Revillagigedo Islands. The pressure gradient on the east side of this ridge is supporting moderate NW winds over the offshore waters west of Baja California Sur. Earlier altimeter data revealed waveheights in the range of 4 to 6 ft for the offshore waters of Mexico. Aside from the potential impact of the developing low pressure over the outer offshore waters of southern Mexico, strong gap winds are possible over the Gulf of Tehuantepec Wed night through Sat night, possibly peaking at minimal gale force Thu night and Fri. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gentle to moderate winds will continue for most areas, although pulses of fresh to strong NE to E gap winds will impact the Papagayo region through Sat. The plume of gap winds could extend W from the Gulf of Papagayo as far W as 100W by Fri evening. Seas within the plume are expected to range between 8 and 10 ft. Combined seas are primarily comprised of long period S to SW swell originating in the southern hemisphere. Recent altimeter satellite passes indicated waveheights ranging between 5 and 7 ft adjacent to Central America and along the coasts of Colombia and Ecuador. The long period swell will maintain combined seas near these heights in these areas for at least the next several days. A tropical wave with an axis along 81W is producing shower and thunderstorm activity over the Gulf of Panama and the waters along the Colombia coast. For further details on this activity see the Tropical Waves section above. REMAINDER OF THE AREA... A 1024 mb high pressure system is centered well N of the area near 34N139W. A ridge extends SE from the high to the Revillagigedo Islands. To the south of this high, the pressure gradient between the ridge and lower pressure over the tropics is generating moderate northeast to east trades north of the ITCZ to about 20N and west of about 120W. Little change in the position of the high or the speed of trades is expected for the next several days. Waveheights in this area will generally run between 5 and 7 ft. Farther south, long-period cross-equatorial swell is maintaining waveheights around 8 ft to the south of 02S and west of 110W. As the swell energy continues to decay, this area of 8 ft seas will respond by slowly subsiding through Thu. A new round of cross- equatorial swell will cause seas south of 05N between 105W and 125W to build to between 7 and 9 ft by Sun evening. $$ Christensen