000 AXPZ20 KNHC 220242 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Mon Aug 22 2016 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 Kay is centered near 21.8N 115.9W at 22/0300 UTC or about 312 nm west-southwest of the southern tip of southern tip of Baja California moving west-northwest, or 300 degrees at 6 kt. The estimated minimum central pressure is 1000 mb, with maximum sustained wind speeds of 45 knots with gusts to 55 kt. Latest Satellite imagery shows a persistent flare up of deep convection over and near the center of Kay in a very symmetrical pattern indicative of a central dense overcast (CDO) feature. The observed convection consists of numerous strong within 45 nm of the center in the southwest quadrant. Scattered moderate convection is elsewhere within 90 nm of the center in the southwest quadrant, and within 60 nm of the center in the southeast quadrant. Kay is forecast to maintain intensity through early on Monday as it approaches near 22.1N 116.7W, then begin to gradually weaken over the next couple of days as it encounters less conducive atmospheric conditions. It is forecast to become a minimal tropical storm by early on Tuesday and a remnant low by Tuesday evening and dissipate on Wednesday. Please read the latest NHC forecast/advisory under AWIPS/WMO headers MIATCMEP2/WTPZ22 KNHC for more details, and the latest public advisory MIATCPEP2/ WTPZ32 KNHC, for more details. ...TROPICAL WAVES... Tropical wave axis extends from 08N97W to 16N96W moving w at 15 kt. Scattered moderate convection is within 30 nm of 12N97W. Tropical wave axis is along 113W/114W from 05N to 16N moving west at 10 to 15 kt. Scattered moderate convection is within 60 nm west of the wave from 08N to 11N. The next tropical wave is forecast to reach the central portions of Honduras and Nicaragua and to northern Costa Rica on Tuesday. Expect increasing showers and thunderstorms in those areas with the wave. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 10N85W to 08N93W to 10N102W to low pressure near 10N108W 1011 mb to 08N116W. Scattered strong convection is within 120 nm south of the axis between 107W and 110W, and within 120 nm north of the axis between 110W and 112W. Scattered moderate to isolated strong convection is within 120 nm south of the axis between 88W and 93W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Tropical Storm Kay continues to impact the waters to west- southwest of the southern tip of Baja California. Light to moderate winds prevail outside of Kay in a relatively weak pressure pattern, which will persist into early next week. Combined seas of 4 to 7 feet outside of Kay will subside gradually early next week. Scattered showers and thunderstorms that earlier developed just inland the east side of far southern Baja California are weakening. Similar activity is just along the coasts of Manzanillo and Cabo Corrientes. This activity being steered to the southwest under a strong upper level north-northeast wind flow. Additional scattered showers and thunderstorms have recently formed along the coast of Mexico between Puerto Angel and Acapulco, and between Manzanillo and Cabo Corrientes. The Gulf of Tehuantepec: northerly offshore winds will continue to pulse to fresh levels during the late night and early morning hours with nocturnal drainage flow. Northerly flow may increase further to fresh to strong beginning on Tuesday night into Wednesday as high pressure builds over the Gulf of Mexico, and tightens the pressure gradient between the Gulf of Mexico and the monsoon trough over the eastern north Pacific. Wavewatch guidance projects that seas will build to 6 to 7 ft in the Gulf with the fresh to strong northerly flow. Seas may possibly reach 8 ft Wednesday if the duration of these winds is longer than anticipated. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Offshore winds will pulse to moderate to fresh through the Gulf of Papagayo and vicinity today and on Monday, with locally strong winds possible early Tuesday as the southern portion of the next tropical wave to enter the far eastern part of the area passes through the areas of southern Honduras and northern Costa Rica further enhancing the gradient there. Light to moderate winds will prevail on either side of the monsoon trough. Combined seas of 4 to 7 feet will slowly subside through Monday as long period south-southwest swell decays. Seas are expected to be about 5 to 6 ft downstream of the Gulf of Papagayo through Monday, then build to 6 to 8 ft Tuesday. ELSEWHERE... The surface analysis reveals a weak pressure pattern with a 1017 mb high centered at 29N127W. The resulting weak pressure gradient is maintaining generally light to gentle winds with seas in the 4 to 6 ft range. These general conditions will prevail into Tuesday. Cross-equatorial southerly swell with combined seas to 8 ft is forecast to propagate into the far southern waters beginning late tonight with the northern edge of the swell train reaching to near 08N between 109W and 119W on Tuesday. $$ Aguirre