000 AXPZ20 KNHC 161615 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Mon Sep 16 2019 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 1600 UTC. ...SPECIAL FEATURES... Hurricane Kiko is centered near 17.3N 123.7 at 16/1500 UTC moving W at 4 kt. Estimated minimum central pressure is 971 mb. Maximum sustained wind speed has diminished to 90 kt with gusts to 110 kt. Kiko remains a small cyclone as it is being affected by northeasterly shear. Numerous strong convection is occurring within 60 nm of the center in the NE and SW quadrants. Elsewhere, scattered moderate to isolated strong convection is noted within 120 nm of the center in the SW quadrant and within 60 nm of the center in the NW quadrant. A westward motion is expected to continue through tonight. A west- southwestward motion is expected Tue and Tue night, followed by a turn back to the west on Wednesday. Gradual weakening is expected during the next couple of days. See latest NHC forecast/advisory under AWIPS/WMO headers MIATCMEP3/WTPZ23 KNHC for more details. Low pressure of 1009 mb is near 11N107W. A tropical wave axis is near 107W from 04N to 18N. Scattered showers and thunderstorms of moderate to strong intensity have increased during the morning within 120 nm of the low in the W and NW quadrants. Scattered moderate convection is within 60 nm east of the wave from 08N to 10N. Overnight satellite data depicted fresh to locally strong winds in the SE and NW quadrants of this system. Conditions are conducive for additional development, and a tropical depression could form within the next two to three days. After mid week, this system is likely to interact or merge with the disturbance to its east described below, and further development after that time is not anticipated. This system has a medium chance of tropical cyclone formation during the next 48 hours. Please see the Eastern North Pacific Tropical Weather Outlook for more information. A large area of disorganized cloudiness and showers centered a few hundred miles south-southwest of the Gulf of Tehuantepec is associated with a tropical wave near 97W. Low pressure of 1009 mb is along the wave axis near 12N97W. Scattered moderate to strong convection is within east of the wave from 11N to 15N. Scattered moderate to isolated strong convection is within west and 60 nm east of the wave. Environmental conditions are expected to be conducive for gradual development, and a tropical depression is likely to form around the middle of the week as the system moves west-northwestward near, or parallel to, the coast of Mexico. This system has a medium chance of tropical cyclone formation through 48 hours and a high chance during the next five days. Please see the Eastern North Pacific Tropical Weather Outlook for more information. ...TROPICAL WAVES... In addition to the tropical waves mention above: A tropical wave with axis along 84W north of 04N was introduced to the 12Z surface analysis. It is moving westward at 10-15 kt. Scattered moderate isolated strong convection is noted within 120 nm west and 60 nm east of the wave from 05N to 08N. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from northwestern Colombia to 11N86W to 11N93W to low pressure near 12N97W 1009 mb and to low pressure near 11N107W 1009 mb. It resumes to the southwest of Kiko near 14N125W and to low pressure near 13N134W 1008 mb and to 11.5N140W. Aside from convection described above with tropical waves and the lows, scattered moderate to isolated strong convection is occurring within 60 nm south of the monsoon trough between 90W and 94W, also within 60 nm south of the monsoon trough between 131W and 134W and from 07N to 10N west of 135W. moderate convection is within 120 nm south of the monsoon trough between 94W and 97W, and within 60 nm south of the monsoon trough between 101W and 105W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... The pressure gradient west of Baja California supports light to gentle northwest winds across these waters, while gentle SE winds are ongoing in the Gulf of California per recent satellite wind data. Farther south, fresh to locally strong northerly winds were noted across the Gulf of Tehuantepec. These winds are expected to diminish by this evening. Overnight altimeter data showed 3-5 ft seas over the waters between Cabo San Lucas and Cabo Corrientes. Moderate to fresh northwest winds will continue over the waters north of Cabo San Lazaro through mid week. Looking ahead, a tropical depression is likely to form around the middle of the week off the coast of Mexico and could produce hazardous marine conditions in the offshore waters. Local marine interests should continue to closely monitor the latest NHC products. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... A broad area of cloudiness and showers near and just west of Central America is associated with the tropical wave near 84W. Moderate to locally fresh southwest winds continue south of the monsoon trough, generally south of 10N, per overnight satellite wind data. Seas across this region are likely in the 6-8 ft range based on earlier altimeter data. Mainly fresh south to southwest winds will continue or the next several days with seas to 8 ft in mixed southwest swell and locally generated wind waves. REMAINDER OF THE AREA... Please see the Special Features section above for information about Hurricane Kiko, as well as the potential for additional tropical development later this week off the coast of Mexico. A high pressure ridge over the northern waters will maintain moderate NE winds north of the monsoon trough and west of 130W through Tue as Kiko continues moving westward. Weak low pressure near 13N134W is producing fresh to locally strong winds and 8-9 ft seas. This feature is expected to remain nearly stationary through Tue, before it begins to drift eastward and become absorbed into the circulation of Kiko later in the week. Elsewhere, low pressure of 1009 mb near 11N107W, as described above under Special Features, is producing fresh to locally strong winds and wave heights of up to 10 ft, primarily in its SE quadrant. This system has a medium chance of tropical cyclone formation during the next 48 hours. A broader area of waveheights in the range of 8-10 ft is present from 07N to 11N between 94W and 108W in association with enhanced southwest flow in the vicinity of two tropical waves. $$ Aguirre