000 AXPZ20 KNHC 120235 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0235 UTC Sat Aug 12 2017 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 0215 UTC. ...SPECIAL FEATURES... Tropical Storm Jova centered near 19.3N 109.8W at 12/0300 UTC or 217 nm S of the southern tip of Baja California moving W-NW at 12 kt. Estimated minimum central pressure is 1003 mb. Maximum sustained wind speed is 35 kt with gusts to 45 kt. Numerous moderate and isolated strong convection within 150 nm in the SW semicircle. Scattered moderate convection is elsewhere within 210 nm in the SW semicircle and also within 150 nm in the E quadrant. Additional tropical storm force/gale force winds are occurring from 18N to 22N within 90 nm of the coast of Mexico due to funneling offshore up against the higher terrain along the coast. Jova is forecast to modestly strengthen through Saturday, then will weaken as it moves over cooler waters, becoming a post- tropical cyclone/ remnant low by Sunday night. See latest NHC forecast/advisory under AWIPS/WMO headers MIATCMEP2/WTPZ22 KNHC for more details. ...TROPICAL WAVES... A tropical wave is N of 07N along 98W/99W moving W at 15 kt. Scattered moderate and isolated strong convection is S of 14N within 210 nm W of the tropical wave axis. This tropical wave will continue to move to the W-NW during the weekend. .INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 09N75W to 07N80W to low pressure near 10N95W to 13N100W, then resumes from 16N104W to 13N120W to 11N140W. Scattered moderate and isolated strong convection is N of a line from 07N77W to 04N82W to 05N84W, and also from 05N to 10N between 87W AND 90W. Scattered moderate convection is from 09N to 12N between 91W and 93W, and also within 180 nm S of the axis between 104W and 140W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section for information on newly developed Tropical Storm Jova. Deep convection has developed over interior portions of NW Mexico during the past few hours with scattered moderate to strong from 23N to 28N. This convection is propagating westward into the Gulf of California. Expect locally higher winds and seas and frequent lightning as the convection moves across the Gulf waters during the next several hours before dissipating. Otherwise, a gentle to moderate breeze will prevail off the northern and central Baja California Peninsula through early next week. Overnight gap winds through the Gulf of Tehuantepec will increase to fresh tonight through Saturday morning, then again Saturday night through Sunday morning, as high pressure builds N of the area in the wake of a tropical wave. Long period southerly swell will propagate toward the coast of southern Mexico from Sunday morning through Monday with seas building to 7 to 9 ft, then gradually decaying through Tuesday. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Nocturnal offshore winds will pulse to fresh in the Gulf of Papagayo during the next several nights/mornings. Otherwise, moderate S to SW winds are expected S of the monsoon trough, with mainly light to gentle variable winds N of the monsoon trough anticipated through Sunday. A new and more robust set of Southern Hemisphere swell is forecast by wave model guidance to cross the equator by early Saturday, bringing seas to 9 ft along the Central American coast Saturday through Monday, decaying thereafter. REMAINDER OF THE AREA... Weak 1012 mb low pressure centered near 11N95W is forecast to drift W through the weekend, possibly merging with the tropical wave just to the W. Some slow development of this low/tropical wave early next week. Otherwise, a broad surface ridge dominates the waters N of the monsoon trough. Gentle to moderate NE winds persist N of the monsoon trough, with moderate to locally fresh flow converging into the monsoon trough from the S-SW, supporting plentiful scattered showers and a few thunderstorms. No major changes are anticipated through the weekend. $$ Lewitsky