000 AXPZ20 KNHC 252125 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1931 UTC Sat May 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... ...Gulf of California Gale Warning... A cold front currently sweeping through Southern California will approach Baja California Norte late today, helping to strengthen SW gap winds across the northern Gulf of California. Strong winds will prevail tonight through Sun night north of 29.5N, with a brief period of gale force winds expected late tonight into Sun morning. Winds will shift to NW to N behind the front early Mon before the front weakens. Wind speeds will then diminish over the Gulf through mid week. ...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, prevails across Central America and the adjacent Caribbean and tropical Pacific waters between about 81W and 100W. This feature is expected to persist for several days and will continue bringing abundant moisture and locally heavy rains across portions of Central America during the next few days. 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 across northern Costa Rica to low pressure near 10.5N88W 1007 mb to 11N100W to 07N115W to 08N122W. The ITCZ continues from 08N122W to 07N130W to beyond 06N140W. Scattered moderate to isolated strong convection is from 06N to 12N between 84W and 100W. Similar convection is also noted from 06N to 10N between 115W and 120W, and from 06N to 09N between 125W and 129W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see special features section above for more on the upcoming gale event over the northern Gulf of California. A weak ridge dominates the offshore forecast waters off Baja California producing mainly light to gentle winds. Seas off the Baja California peninsula remain in the 6-8 ft range in NW swell, and 5-7 ft in mixed swell over the remainder of the open waters off the coast of Mexico. High pressure well NW of the region will build modestly SE into the region over the next few days and act to strengthen the pressure gradient across the offshore waters. This will increase winds into the moderate to fresh range through early Mon, with diurnal heating on Mon and Tue yielding areas of strong afternoon through early evening winds along the prominent points and capes of the Baja peninsula. NW swell moving through the regional waters today will diminish tonight through Sun and allow for seas to subside by 1-2 ft during that time. Gulf of Tehuantepec: Fresh to strong northerly winds will pulse across the Gulf of Tehuantepec region late tonight into early Sun. Seas will build to 8-9 ft by early Sun morning before subsiding below 8 ft by Sun evening. 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. Light to gentle SW to W winds prevail S of the monsoon trough, with seas in the 4-7 ft range. Light to moderate winds of varying direction, and seas in the 5-6 ft range prevail N of the monsoon trough. Low pres 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 will strengthening and shifting northward with the trough. Seas will build to 8-12 ft by mid week in this enhanced monsoon flow. REMAINDER OF THE AREA... High pressure well NW of the area extends a ridge SE to near 18N115W. The pressure gradient between the ridge and lower pressures in the vicinity of the ITCZ is supporting fresh NE winds across much of the area N of the ITCZ and W of 120W. The ridge will build modestly SE into the region over the weekend with the main repercussion being to veer winds more E to NE with little change in strength. SW swell producing seas to 8 ft covers the forecast waters from 04N to 10N between 95W and 115W, and will dominate seas there through Sun, before new SW swell enters the southern waters, and propagate northward through mid week. This will result in a large area of seas 8 ft or greater south of 10N between 85W and 122W by late Mon. $$ GR