For the North Atlantic...Caribbean Sea and the Gulf of Mexico: 1. Central Tropical Atlantic: Shower and thunderstorm activity has increased in association with a tropical wave located about 950 miles east-southeast of the southern Windward Islands. Environmental conditions appear conducive for further development, and a tropical depression is likely to form during the next couple of days before the system reaches the Windward Islands Tuesday night or possibly while moving westward across the southern Caribbean Sea Wednesday through Friday. A NOAA Hurricane Hunter aircraft is scheduled to investigate the system this afternoon. Interests in the Windward Islands and along the northeastern coast of Venezuela should monitor the progress of this system, and tropical storm watches or warnings could be required for portions of these areas later today. Regardless of development, locally heavy rainfall is possible over the Windward Islands and the northeastern coast of Venezuela Tuesday night and Wednesday. * Formation chance through 48 hours...high...70 percent. * Formation chance through 5 days...high...90 percent. 2. Northern Gulf of Mexico: Disorganized showers and thunderstorms over the north-central and northeastern Gulf of Mexico are associated with a trough of low pressure. Development of this system is expected to be slow to occur while it moves west-southwestward at about 10 mph toward the northwestern Gulf of Mexico and approaches the coasts of southern Texas and northeastern Mexico during the next few days. * Formation chance through 48 hours...low...10 percent. * Formation chance through 5 days...low...20 percent. 3. Eastern Tropical Atlantic: A tropical wave located several hundred miles southwest of the Cabo Verde Islands is producing disorganized showers and thunderstorms. Environmental conditions could become conducive for gradual development later this week while the system moves west-northwestward at around 15 mph over the central tropical Atlantic. * Formation chance through 48 hours...low...near 0 percent. * Formation chance through 5 days...low...20 percent.