FZUS52 KJAX 091218 CWFJAX Coastal Waters Forecast for Northeast Florida/Southeast Georgia National Weather Service Jacksonville FL 818 AM EDT Thu Jul 9 2026 Atlantic Coastal Waters from Altamaha Sound GA to Flagler Beach FL out to 60 nm. Seas are provided as a range of the average height of the highest 1/3 of the waves, along with the occasional height of the average highest 1/10 of the waves. AMZ400-100330- Synopsis for Altamaha Sound GA to Flagler Beach FL out to 60 nm- 818 AM EDT Thu Jul 9 2026 .SYNOPSIS... High pressure ridge will remain anchored across central and south Florida this week as low pressure troughing develops to the north. This pattern will maintain a southwest flow through early afternoon followed by late afternoon and evening wind surges from the south and an increase to Small Craft Exercise Caution wind speeds. The offshore flow will allow for a slight chance of afternoon and evening thunderstorm over the local coastal waters through Friday, with increased chances of thunderstorms Saturday through early next week. Mariners should expect locally strong wind gusts and frequent lightning with any developing thunderstorms. .GULF STREAM... The approximate location of the west wall of the Gulf Stream as of Jul 08, 2026 at 0000 UTC... 46 nautical miles east of Flagler Beach. 44 nautical miles east of Saint Augustine Beach. 56 nautical miles east southeast of Jacksonville Beach. 71 nautical miles east southeast of St Simons Island. This data derived from NCEP Global RTOFS model. $$ AMZ450-452-454-100330- Coastal waters from Altamaha Sound to Fernandina Beach FL out 20 NM- Coastal waters from Fernandina Beach to St. Augustine FL out 20 NM- Coastal waters from St. Augustine to Flagler Beach FL out 20 NM- 818 AM EDT Thu Jul 9 2026 ...SMALL CRAFT EXERCISE CAUTION IN EFFECT FROM 6 PM EDT THIS EVENING THROUGH LATE TONIGHT... .REST OF TODAY...Southwest winds 5 to 10 knots, becoming south 10 to 15 knots this afternoon. Seas 2 to 3 feet. Wave Detail: Southeast 3 feet at 5 seconds and east 2 feet at 9 seconds. Intracoastal waters a moderate chop. A slight chance of showers and thunderstorms this afternoon. .TONIGHT...South winds 15 to 20 knots, becoming southwest 10 to 15 knots after midnight. Seas 2 to 4 feet, occasionally to 5 feet. Wave Detail: Southeast 3 feet at 5 seconds. Intracoastal waters choppy. A slight chance of showers and thunderstorms in the evening. .FRIDAY...Southwest winds 5 to 10 knots, becoming south 15 to 20 knots in the afternoon. Seas 2 to 4 feet, occasionally to 5 feet. Wave Detail: Southeast 3 feet at 5 seconds. Intracoastal waters choppy. .FRIDAY NIGHT...South winds 15 to 20 knots, becoming southwest 10 to 15 knots after midnight. Seas 2 to 4 feet, occasionally to 5 feet. Wave Detail: Southeast 4 feet at 5 seconds. Intracoastal waters choppy. .SATURDAY...Southwest winds 5 to 10 knots, becoming south 15 to 20 knots in the afternoon. Seas 2 to 3 feet. Wave Detail: Southeast 3 feet at 5 seconds. Intracoastal waters choppy. A slight chance of showers and thunderstorms in the afternoon. .SATURDAY NIGHT...Southwest winds 10 to 15 knots. Seas 2 to 3 feet. Wave Detail: Southeast 3 feet at 5 seconds. Intracoastal waters a moderate chop. A chance of showers and thunderstorms in the evening. .SUNDAY...Southwest winds 5 to 10 knots. Seas 2 to 3 feet. Intracoastal waters light chop. A chance of showers and thunderstorms through the night. A slight chance of showers and thunderstorms after midnight. .MONDAY...Southwest winds 5 to 10 knots, becoming west. Seas around 2 feet. Intracoastal waters light chop. A chance of showers with a slight chance of thunderstorms in the morning, then thunderstorms likely in the afternoon. Showers through the night. A chance of thunderstorms in the evening, then achance of showers after midnight. Winds and waves higher in and near thunderstorms. $$ AMZ470-472-474-100330- Waters from Altamaha Sound GA to Fernandina Beach FL from 20 to 60 NM- Waters from Fernandina Beach to St. Augustine FL from 20 to 60 NM- Waters from St. Augustine to Flagler Beach FL from 20 to 60 NM- 818 AM EDT Thu Jul 9 2026 ...SMALL CRAFT EXERCISE CAUTION IN EFFECT FROM 6 PM EDT THIS EVENING THROUGH LATE TONIGHT... .REST OF TODAY...Southwest winds around 10 knots, becoming south this afternoon. Seas 2 to 3 feet. Wave Detail: South 3 feet at 5 seconds and southeast 3 feet at 9 seconds. .TONIGHT...Southwest winds 10 to 15 knots. Seas 3 to 4 feet, occasionally to 5 feet. Wave Detail: South 3 feet at 5 seconds and southeast 2 feet at 9 seconds. .FRIDAY...Southwest winds 5 to 10 knots, becoming south 10 to 15 knots in the afternoon. Seas 2 to 3 feet. Wave Detail: South 3 feet at 5 seconds and southeast 3 feet at 8 seconds. .FRIDAY NIGHT...South winds 15 to 20 knots, becoming southwest 10 to 15 knots after midnight. Seas 3 to 5 feet, occasionally to 6 feet. Wave Detail: South 4 feet at 5 seconds and southeast 2 feet at 8 seconds. .SATURDAY...South winds 10 to 15 knots. Seas 2 to 4 feet, occasionally to 5 feet. Wave Detail: South 3 feet at 5 seconds and southeast 3 feet at 8 seconds. .SATURDAY NIGHT...Southwest winds 10 to 15 knots. Seas 3 to 4 feet, occasionally to 5 feet. Wave Detail: South 3 feet at 5 seconds and southeast 3 feet at 8 seconds. A slight chance of showers and thunderstorms in the evening. .SUNDAY THROUGH MONDAY...West winds 5 to 10 knots. Seas 2 to 3 feet. Showers likely with a chance of thunderstorms. Winds and seas higher in and near thunderstorms. $$