000 AXPZ20 KNHC 281515 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1515 UTC Tue May 28 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 1200 UTC surface analysis and satellite imagery through 1500 UTC. ...SPECIAL FEATURES... ...Heavy Rainfall Potential Over Central America... A large low level cyclonic circulation that is typical for this time of the year, called a Central American Gyre, is forecast to persist across the far eastern tropical Pacific and Central America for the next several days. Abundant moisture and increasing instability are expected through Wed, which could lead to a very significant rainfall event over portions of Central America. Life-threatening flash flooding and mudslides will be possible in areas of mountainous terrain. Please refer to your local meteorological service for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 11N86W to 1008 mb low pressure near 11N88W to 09N130W. The ITCZ continues from 09N130W to beyond 06N140W. Scattered moderate to isolated strong convection is observed from 06N to 10N between 85W and 95W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A ridge extends across the forecast waters west of the Baja California peninsula. Recent scatterometer and altimeter satellite data along with various ship observations indicate fresh to strong winds and 6 to 8 ft prevail west of the Baja California peninsula. Light to gentle winds, with seas in the 4-6 ft range prevail elsewhere over the open waters off Mexico. Light winds and seas 2 ft or less prevail over the Gulf of California. High pressure will weaken slightly by Wed. This will diminish winds to 20 kt or less west of the Baja California peninsula, with seas subsiding below 8 ft. SW winds will strengthen south of the Gulf of Tehunatepec by midweek. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Please see the Special Features section for more information about the Central American Gyre, which will continue to bring locally heavy rains to parts of Central America and the adjacent offshore waters through at least mid week. Latest surface observations indicate moderate to fresh S to SW winds south of the monsoon trough, with seas in the 6-8 ft range. Moderate to locally fresh winds, and seas of 5-6 ft prevail north of the monsoon trough. 1008 mb low pressure embedded within the broad gyre remains west of the Gulf of Papagayo. The monsoon trough and the embedded low pressure will lift northward tonight. Seas will also build to 8-11 ft by mid week as locally generated wind waves in the enhanced monsoon flow combines with cross equatorial SW swell. REMAINDER OF THE AREA... A ridge extends from 1027 mb high pressure centered near 33N136W southeastward through the Revillagigedo Islands. The pressure gradient between the ridge and lower pressure in the vicinity of the ITCZ is supporting moderate to fresh NE winds across much of the area north of the ITCZ and west of 120W. Moderate to fresh winds will continue to prevail over this area the next several days. Long period cross equatorial SW swell will continue to dominate much of the forecast waters. Seas 8 ft or greater cover the waters south of 11N between 95W and 130W. Seas will slowly subside the next couple of days, with areal coverage of seas 8 ft or greater decreasing. $$ Christensen