000 AXNT20 KNHC 160933 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Sun Jun 16 2024 Tropical Weather Discussion for North America, Central America Gulf of Mexico, Caribbean Sea, northern sections of South America, and Atlantic Ocean to the African coast from the Equator to 31N. 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 FEATURES... Heavy Rainfall over Central America and Mexico: A broad area of low pressure is centered over northern Central America and southern Mexico. This weather pattern is known as a Central American Gyre (CAG), and often persists for several days resulting in life- threatening conditions that include flooding and mudslides. With the current CAG, the circulation is producing strong SW monsoonal flow in the eastern north Pacific that will advect abundant tropical moisture northward into the coastal terrain of Central America and southern Mexico. The pattern is expected to persist through at least the middle of this week across northern Central America and southern Mexico, with the threat to life and property increasing as the event persists. The main areas impacted by the heavy rainfall will be northwest Nicaragua, southwest Honduras, northwest Nicaragua, and coastal sections of Honduras, El Salvador, Guatemala, and the Mexican state of Chiapas. Heavy rainfall is also possible across Quintana Roo, Yucatán, Tabasco, Veracruz, NE Queretero, NE Hidalgo, and San Luis Potosi this week. The persistence of the moist pattern will create very hazardous conditions in the region that could be life-threatening. Please refer to your local meteorological office bulletins for more detailed information. ...TROPICAL WAVES... The axis of an eastern Atlantic tropical wave is near 23W, from 15N southward, moving westward around 10-15 kt. Scattered moderated convection is from 07N to 09N within 60 nm of the wave axis. The axis of a central Atlantic tropical wave is analyzed near 54W, extending from 17N southward. It is moving west at 10-15 kt. Scattered moderate convection is from 06N to 10N between 50W and 54W. ...MONSOON TROUGH/ITCZ... The monsoon trough enters passes off the coast of Africa near 13N17W to 06N31W. The ITCZ continues from 06N31W to 04N51W. Scattered moderate convection is noted from 03N to 07N between 29W and 50W. GULF OF MEXICO... Please read the SPECIAL FEATURES section for information on the possibility of heavy rainfall across Quintana Roo, Yucatán, Tabasco, Veracruz, and San Luis Potosi this week. A Central American Gyre is currently over southern Mexico and Central America. A surface trough extends from 26N91W to just west of the Yucatan peninsula. Moderate to fresh winds are noted S of 25N and E of 91W, with gentle to moderate winds elsewhere. Seas are in the 4-6 ft range E of 90W, and 2-4 ft W of 90W. For the forecast, the gyre center is expected to persist through the middle of this week, while shifting WNW to NW into the SW Gulf of Mexico. Environmental conditions appear conducive for a tropical cyclone to develop from this broad area of low pressure, and a tropical depression could form over the southwestern Gulf during the middle part of this week, then move west or west- northwestward. Active convection across the southeast Gulf, along with increasing winds and building seas, is expected to shift westward with this system into the middle part of the week, impacting the south-central and northwest Gulf. CARIBBEAN SEA... Please read the SPECIAL FEATURES section for information on the potential for heavy rainfall across Quintana Roo and Yucatán this week. A Central American Gyre is currently over southern Mexico and Central America. The circulation around the gyre is supporting fresh to strong SE winds over the NW Caribbean. Moderate to fresh winds are noted elsewhere. Seas are in the 6-8 ft range over the NW Caribbean, and 4-6 ft elsewhere except the far NE Caribbean where seas are in the 3-4 ft range. For the forecast, the gyre center is expected to persist through the middle of this week, while shifting WNW to NW into the Gulf of Mexico. The resultant pattern will produce fresh to strong SE winds and scattered showers and thunderstorms across portions of the western and northwestern Caribbean today, then shift across the NW Caribbean and Gulf of Mexico tonight through Wed. ATLANTIC OCEAN... A surface trough extends from 31N70W to central Florida. Scattered showers and thunderstorms persist east of the trough. A second trough extends from 30N62W to 21N70W. Scattered showers are within 60 nm east of this trough N of 25N. To the east of 55W, high pressure prevails. Light to gentle winds generally prevail W of 55W, with seas in the 2-4 ft range. Elsewhere, moderate to fresh winds prevail, with seas in the 4-7 ft range. For the forecast west of 55W, the trough NE of the Bahamas will shift eastward and exit the region through early this week, with active convection continuing ahead of it. Expect fresh E winds north of 26N and west of 65W by Tue, as high pressure builds north of the area behind the exiting trough. Low pressure is forecast to develop a few hundred miles northeast of the central Bahamas by midweek. Environmental conditions could be conducive for some development of this system thereafter while it moves westward or west- northwestward. $$ AL