790 AXPZ20 KNHC 080403 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Wed Aug 8 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 0000 UTC surface analysis and satellite imagery through 0300 UTC. ...SPECIAL FEATURES... Hurricane John centered near 19.2N 111.1W at 0300 UTC or 300 nm S of The Southern Tip Of Baja California moving NW at 9 kt. Estimated minimum central pressure is 969 mb. Maximum sustained winds are 90 kt with gusts to 110 kt. Numerous moderate to strong convection is within 150 nm of the center, except to 60 nm in the NW quadrant. Scattered moderate isolated strong convection is noted elsewhere within 240 nm either side of a line from 23N110W to 14N106W. See latest NHC forecast/advisory under AWIPS/WMO headers MIATCPEP2/WTPZ32 KNHC for more details. Tropical Storm Kristy centered near 14.2N 127.8W at 0300 UTC, moving W at 7 kt. Estimated minimum central pressure is 1002 mb. Maximum sustained winds are 45 kt with gusts to 55 kt. Scattered moderate to strong convection is within 30 nm of the center, and scattered moderate isolated strong convection is elsewhere within 75 nm N and 150 nm S of the center. See latest NHC forecast/advisory under AWIPS/WMO headers MIATCPEP3/WTPZ33 KNHC for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough stretches from 09N78W to 09N110W. Scattered moderate convection is noted within 60 nm either side of the trough axis west of 105W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... See the Special Features Paragraph above for details on Hurricane John. John is expected to affect the offshore waters between Manzanillo and Baja California Sur with winds and seas tonight through Friday night. Gulf of Tehuantepec: Moderate to fresh nocturnal northerly drainage flow is expected in and up to 120 nm downstream of the gulf through Fri night. Gulf of California: Large southerly swell from John will cause seas S of 25N to build to 8-12 ft with S winds will increase to 20-25 kt through Wed night as the hurricane move NW, passing SW of Cabo San Lucas. Outside of the tropical cyclones, a weak pressure pattern will be in place through the end of the week due to weak ridging NW of the region. A large extratropical low pressure system west of California and Oregon will maintain a weakened pressure gradient and support gentle to moderate winds over forecast waters. The extratropical low is expected to weaken this weekend, allowing the ridge to rebuild. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Fresh NE to E nocturnal flow is expected through the end of this week. Gentle to occasionally moderate E winds are forecast elsewhere N of the monsoon trough, which will meander between 07N and 11N. Moderate to locally fresh S to SW winds are expected S of the trough through the end of this week. 4-6 ft seas will generally prevail, except for 6- 7 ft seas near the Galapagos Islands. REMAINDER OF THE AREA... See the Special Features Paragraph above for details regarding Hurricane John and Tropical Storm Kristy which will affect the waters N of 10N during the next several days. Large swell greater than 8 ft will propagate well away from from Hurricane John through the end of this week as a very large system. The areas of 8 ft seas generated by swell from Hurricane John and Tropical Storm Kristy will merge on Thu, with a large area of 8 ft seas likely enveloping most of the waters N of 15N and W of 110W through the remainder of this week. Ridging N of the area will weaken during the next few days as John and Kristy dominate the synoptic environment. John will have the most effect on the ridge due to its large size. Strong NW winds west of California will produce N swell that will cause seas to build to 7-8 ft N of 30N between 120W and 124W tonight. $$ Mundell