000 AXPZ20 KNHC 182222 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Mon Jun 18 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 1800 UTC surface analysis and satellite imagery through 2115 UTC. ...SPECIAL FEATURES... The center of Tropical Depression Carlotta is near 18.1N 103.3W at 18/2100 UTC, or 65 nm W of Lazaro Cardenas, Mexico, moving NW at 4 knots. The estimated minimum central pressure is 1007 mb. The maximum sustained winds remain at 25 knots with gusts to 35 knots. Please read the latest NHC forecast/advisory under AWIPS/WMO headers MIATCPEP4/WTPZ34 KNHC for more details. Scattered moderate to strong convection is noted within 75 nm across the east and 120 nm across the west semicircles. Rough seas and surf can be expected in the nearshore waters of southern Mexico associated with this system, especially from Tecpan De Galeana to Lazaro Cardenas. Carlotta is expected to continue moving slowly NW and generally parallel to the coast. Interaction with the mountainous Mexican terrain across this area is expected to cause dissipation of the central circulation of the depression within the next 12 to 24 hours. However, areas of heavy rain will continue over southern portions of the states of Guerrero, Michoacan, and Colima during this time. ...TROPICAL WAVES... A tropical wave is analyzed along 92W/93W moving slowly westward near 10 kt. Convection associated with this wave is occurring along the monsoon through with isolated convection elsewhere both to the east and west of the wave axis. This wave will also provide moisture for active convection across the coastal zones of Guatemala and southeastern Mexico during the next 24 to 48 hours. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 08N75W TO 09N91.5W TO 08.5N101W, where it breaks to the SE of Carlotta, then resumes from 113N109W TO 08.5N125W, where it transitions to ITCZ, continuing to 09N136W to beyond 07N140W. Scattered to numerous moderate to strong convection is noted from 03.5N to 09.5N from 90W eastward to the coast of Colombia. Scattered moderate to strong convection is noted from 06N to 12N between 106W and 128W, and within 150 nm either side of the ITCZ between 131W and 140W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please read the Special Features section for details about Tropical Depression Carlotta. Moderate NW winds prevail across the offshore waters of Baja California this afternoon, with afternoon heating enhancing winds to near 20 kt across a few coastal areas. This pattern is expected to continue for the next few days, with late afternoon heating enhancing winds to around 20 kt through the evening hours. Seas currently range 5 to 7 feet in NW swell and will diminish very slightly through Wednesday. Increasing NW to N winds are forecast along and offshore of southern and central California, which will generate an increase in northerly swell moving into the Baja waters Thu through Sat. Gulf of California: Weak low pressure prevails across the far northern Gulf, producing light and variable winds N of 31N and moderate to fresh W to SW winds From 30N to 31N. Otherwise, light to gentle W to NW are expected elsewhere across the Gulf during the next few days, with afternoon heating leading to 15 kt seabreezes each day. Seas of 3 feet or less are expected across north and central section through Wed, and 3 to 5 feet near the entrance of the Gulf. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... The monsoon trough will meander between 07.5N and 10N for the next few days. Long period SW swell will maintain seas of 5 to 7 ft S of 10N through tonight before subsiding. A new and larger pulse of long period SW to S swell will reach the waters W of Ecuador by Thursday, with combined seas building to 7 to 9 ft, except in the lee of the Galapagos Islands. Light to gentle winds will prevail elsewhere N of the monsoon trough, and gentle to moderate S to SW winds will prevail S of the monsoon trough. REMAINDER OF THE AREA... Northerly swell propagating into the northern waters N of 25N W of 118W, has subsided this afternoon east of 125W. Residual swell is maintaining seas 7 to 8 feet N of 24N and west of 125W, and will gradually diminish during the next 24 hours, leaving seas in the 5 to 7 ft range through mid week. Light to gentle anticyclonic wind flow covers the area north of 15N and westward of 115W, as a weak and narrow ridge extends SE into the area from a 1023 mb high near 37N137W. The ridge will change little in strength and orientation through Wed before ti begins to strengthen. Mainly moderate tradewinds and seas less than 8 ft will prevail through Wed south of this ridge, before the strengthening high produces a modest increase in tradewinds and seas south of 26N and west of 128W Thu and Fri. Long period cross-equatorial SW swell has begun to subside across the eastern waters today, with afternoon seas generally 4 to 7 ft. However, a new and larger pulse of SW to S swell is currently begin generated across and east of French Polynesia, and will cross the equator on Wed, and arrive across the regional waters Wed night. Seas across the offshore waters of Central America will build Thu through Fri, reach 6-9 ft on Friday. $$ Stripling