000 AXPZ20 KNHC 020918 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Sat Sep 2 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...SPECIAL FEATURE... Tropical Storm Lidia is centered SE of Punta Eugenia near 27.2N 113.6W at 2 am PDT moving NW at 11 kt, with estimated minimum central pressure of 994 mb. Maximum sustained winds are 40 kt with gusts to 50 kt. Latest satellite imagery shows scattered moderate to strong convection within 90 nm NE of the center, and scattered moderate isolated strong convection elsewhere from 25N to 29N between 110W and 115W. Very heavy rainfall along the Baja California peninsula has the potential for life-threatening flash floods and mudslides. Lidia will move NW along the west coast of the Baja California Peninsula today, then move offshore and weaken to a depression tonight. Please see the latest NHC forecast/advisory under AWIPS/WMO headers MIATCMEP4/WTPZ24 KNHC for more details, and for the Public Advisory please see the latest NHC forecast/advisory under AWIPS/WMO headers MIATCPEP4/WTPZ34 KNHC. ...TROPICAL WAVES... A tropical wave is analyzed N of 10N along 89W, moving westward at 10 to 15 kt. Convection associated with the wave is inland over Guatemala and southern Mexico. A tropical wave is analyzed N of 10N along 102W with a 1010 mb surface low along on the wave axis near 15N102W. The system is moving W at 10 to 15 kt. Scattered moderate isolated strong convection is observed within 30 nm W and 120 nm E of the wave. ..INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 10N85W to 13N104W, then resumes from 17N123W to 16N128W to 13N132W to 12N140W. Scattered moderate isolated strong convection is within 150 nm N of the trough between 92W and 97W. Similar convection is occurring in the gap between monsoon trough segments over an area from 11N to 16N between 105W and 117W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Refer to special features for information on Tropical Storm Lidia. A weak ridge will build eastward along 23N Sun as Lidia exits the area, with a moderate to fresh NW breeze setting up across the open waters W of the Baja California Peninsula. Gulf of Tehuantepec: Moderate offshore nocturnal flow is expected through Monday. Model guidance indicates an early season cold front reaching southern Mexico could initiate very strong gap winds Thu night and Fri. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Gentle to locally moderate offshore nocturnal flow is expected tonight, becoming moderate to fresh Sun night. Otherwise, light and variable flow is expected N of the monsoon trough axis through early next week, while moderate to locally fresh southerly winds are expected to the S of the trough axis. REMAINDER OF THE AREA... Broad cyclonic flow dominates most of the area N of 12N between 104W and 126W. Abundant deep moisture throughout this region has very dry air aloft NW of the area based on water vapor imagery. Mostly gentle NE winds exist N of the monsoon trough W of 126W with 5-6 ft seas. Fresh southerly monsoonal winds and seas of 5- 8 ft are observed S of 15N between 100W and 130W primarily in mixed SE and SW cross-equatorial swell. The swell is forecast to begin to dissipate on Sunday allowing for seas to slowly subside into early next week. $$ Mundell