613 AXPZ20 KNHC 270902 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 514 UTC Mon May 27 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 0600 UTC surface analysis and satellite imagery through 0900 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. This will continue bringing abundant moisture and areas of heavy rainfall across portions of Central America. Computer model forecasts have begun to indicate the chance for a further increase in moisture and instability associated with this feature Tue through Wed, which could lead to a very significant rainfall event. 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 09N86W to 13N97W to 09N105W to 09N124W. The ITCZ extends from 09N124W to 05N140W. Scattered moderate to strong convection is noted from 12N to 15N between 91W and 98W. Scattered moderate isolated strong convection was noted from 05N to 10N between 85W and 100W. Scattered moderate convection was noted from 05N to 10N between 106W and 130W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gulf of California: A cold front is moving across the northern Gulf of California. Fresh to strong SW to W winds and seas in the 4-6 ft range prevail. Winds will diminish to 20 kt or less today. A cold front extends from Baja California Norte to near 22N130W, with high pressure building in its wake. A trough extends along the Gulf of California. The pressure gradient between the building high pressure and the trough over the Gulf of California is supporting fresh to strong winds over the waters off Baja California Sur. High pressure will continue to build. This will further tighten the pressure gradient across the offshore waters to support fresh to locally strong NW to N winds across the waters off Baja California through Tue night, with seas building into the 6 to 8 ft range. 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. Gentle to moderate SW to W winds prevail S of the monsoon trough, with seas in the 4-7 ft range. Moderate to locally fresh winds, and seas in the 5-6 ft range prevail N of the monsoon trough. Low pressure of 1008 mb embedded within the broad gyre will meander offshore the coast of Nicaragua the next couple of days. The monsoon trough will lift northward through the early part of the week, with southerly monsoon flow strengthening, potentially to 20-25 kt by Tue. Seas will build to 8-12 ft by mid week in this enhanced monsoon flow. REMAINDER OF THE AREA... High pressure of 1027 mb centered NW of the area near 34N139W extends a ridge SE to near 26N118W. 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 N of the ITCZ and W of 120W. Moderate to fresh winds will continue to prevail over this area the next several days. SW cross equatorial swell will dominate the forecast waters S of 10N and W of 95W for the next few days, with new swell arriving late Tue. Seas 8 ft or greater will cover much of the forecast waters S of 11N between 85W and 111W by late Tue. $$ AL