000 AXPZ20 KNHC 131538 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1449 UTC Sat Oct 13 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 1200 UTC surface analysis and satellite imagery through 1500 UTC. ...SPECIAL FEATURES... Satellite-derived surface winds and radar data from Acapulco indicate that a small but well-defined low pressure system has developed less than 100 miles southwest of Acapulco, Mexico. Associated shower and thunderstorm activity has increased and become much better organized overnight, and further development of the low is possible during the next few days while the system moves slowly westward to west-northwestward parallel to the southern coast of Mexico. However, only a slight deviation to the right or north of the expected track would bring the small disturbance and its heavy rains closer to or even inland along the southwestern coast of Mexico. Interests in this area should monitor the progress of this system. See latest Tropical Weather Outlook under AWIPS/WMO Headers MIATWOEP/ABPZ20 KNHC for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from southern Guatemala near 15N90W to 1007 mb low pressure system located near 16N100W to 13N110W to 11N120W to 11N130W to beyond 09N140W. Scattered moderate convection is from 10N-14N between 87W-95W, and from 07N-10N between 104W-108W. Scattered moderate to isolated strong convection is noted on either side of the monsoon trough from 08N-11N between 110W-130W, and from 07N-13N between 130W-134W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A ridge dominates the offshore waters W of Baja California Peninsula producing mainly light to gentle winds. Seas of 7 to 8 ft are still noted per altimeter data just W of Baja California Sur, and near the entrance of the Gulf of California. These seas, associated with long period SW swell, are expected to subside to 5-6 ft by tonight. Gentle to moderate NW-N winds are expected beginning on Mon as high pressure builds across the northern forecast waters. Gulf of California: Surface troughing over the Baja Peninsula will support light to gentle winds over the Gulf of California through Sun night. On Mon, strong to near gale force NW winds are expected N of 27N in response to very strong high pressure building over the Great Basin of the United States. Winds could gust to gale force for the waters N of 29N when this event peaks late on Mon. Seas to 9 ft are possible in the northern Gulf Monday, then seas will gradually subside below 8 ft by Tue evening as winds die down. Gulf of Tehuantepec: Next gap wind event is forecast to start early on Wed with seas rapidly building to 10 ft by Wed night. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate to fresh SW monsoonal flow will continue across the region through Tue, with showers and thunderstorms expected to continue along the Pacific coast of Central America. Heavy rainfall during the past few days has already produced significant flooding in Nicaragua. Long period cross-equatorial southwest swell will maintain 5 to 8 ft seas across the forecast area during this time frame. Looking ahead, global models are indicating development of broad low pressure over the southwest Caribbean. This area of low pressure will move west over Central America next week, enhancing convection across Panama and Costa Rica. REMAINDER OF THE AREA... A cold front will enter the NW waters early on Tue. Moderate to fresh monsoonal flow will generally prevail until the middle of next week across the waters S of 10N with seas to 9 ft. Gentle to moderate trades and seas of 5 to 7 ft can be expected for the waters N of the monsoon trough, S of 20N and W of 120W. $$ GR