000 AXPZ20 KNHC 211004 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Sun Aug 21 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 0600 UTC surface analysis and satellite imagery through 0830 UTC. ...SPECIAL FEATURES... The center of Tropical Storm Kay at 21/0900 UTC is near 21.0N 114.1W, or about 260 nm to the WSW of the southern tip of Baja California. Kay is moving northwestward, or 305 degrees, 6 knots. The estimated minimum central pressure is 1005 mb. The maximum sustained wind speeds are 35 knots with gusts to 45 knots. Convective precipitation: numerous strong within 45 NM in the SW quadrant. Scattered strong elsewhere within 45 nm of the center in the E quadrant, and within 75 NM of the center in the SW quadrant. 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... A tropical wave is along 91W/93W from 18N southward, moving westward 15 to 20 knots. The northern part of the wave is moving through western Guatemala near the border with Mexico. Convective precipitation: scattered to numerous strong within 90 NM of the coast of Guatemala. A tropical wave is along 109W/111W from 15N southward. The wave is moving westward 10 to 15 knots. Convective precipitation: Scattered moderate to isolated strong from 07N to 12N between 108W and 113W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough is along 10N86W TO 11N88W TO 09N95W TO 10N103W TO 07N112W TO 08N114W. Convective precipitation: Scattered moderate to isolated strong within 240 NM S of the monsoon trough between 83W and 88W...within 210 NM to the south of the monsoon trough between 90W and 96W...within 120 NM to the north of the monsoon trough between 93W and 95W, and within 75 nm to the north of the monsoon trough between 103W and 104W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Tropical Storm Kay continues to impact the waters that are to the southwest of the 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. 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. The northerly flow may pulse briefly to moderate to strong intensity around sunrise on Tuesday with passage of the forecast tropical wave. Model guidance then suggests that the northerly flow may increase further to fresh to strong intensity on Wednesday and Thursday of next week as high pressure ridging from the Gulf of Mexico presses southwest across southeastern Mexico. 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, and then to strong on Tuesday. Light to moderate winds will prevail on either side of the monsoon trough. Combined seas of 4 feet to 7 feet will slowly subside through Monday as supporting long period south- southwest swell decays. Seas are expected to be about 5 to 6 ft downstream of the Gulf of Papagayo through Monday. A tropical wave, currently along 91W/93W, will move into the Gulf of Tehuantepec today and tonight. ELSEWHERE... High pressure of 1030 mb centered northwest of the area extends a weakening ridge southeastward to 27N140W and to 21N120W. 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 Monday. Cross-equatorial mixed southeast and southwest swell, originating from a long- duration ongoing swell event in the South Pacific Ocean, is forecast to propagate into the far southern waters of the high seas area during the early morning hours of Monday, to the south of 02S between 110W and 118W. The resultant seas are forecast to reach 8 feet. Wavewatch model guidance projects this area of swell to spread eastward to near 98W by Mon night. $$ mt