FXUS62 KILM 050549 AFDILM Area Forecast Discussion National Weather Service Wilmington NC 149 AM EDT Mon Aug 5 2024 .SYNOPSIS... Bermuda high pressure to the east maintains an influence through Monday, while Tropical Storm Debby starts making landfall on the Florida Gulf Coast. Conditions start to deteriorate Monday night into Tuesday in association with Debby. Exceptionally heavy rainfall will be possible through Thursday, with some parts in the Grand Strand region possibly recording over a foot of rain. && .UPDATE... Cluster of showers currently moving across the Cape Fear region, with light radar returns around I-95. May see some patchy fog inland before sunrise. 6z aviation discussion below. && .NEAR TERM /THROUGH TODAY/... WV imagery shows a well defined trough moving through the Great Lakes with a healthy stream of moisture downstream. This moisture and the resulting clouds have limited instability for a slower onset of shallow and even moreso deep convection. Radar echoes have increased as of late and lightning has picked up a little. Both trends will reverse heading into tonight with loss of daytime heating. Tropical moisture increases from the south late tonight heading into Monday but the heavy rain will be relegated until after the period and have thus held off on an almost certain eventual Flood Watch. Similar to today the widespread cloud cover will keep temperatures a bit below climatology Monday whereas tonight will run a few degrees warm. && .SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/... Debby will be gradually exiting the Georgia-Florida coast this period and will linger over the extreme western Atlantic close to coastal SC. The center of Debby looks to have shifted more to the east in the latest forecast, but that doesn't necessarily change the impacts for here. This is when the fire hose turns on, particularly for the northeast SC coast. Overcast skies in place, with plenty of tropical moisture to work with. Flooding rain threat continues to be in play here, with life-threatening impacts possible. Rough surf is also a big threat here, with dangerous rip currents and hazardous marine conditions likely through much of this week. Highs in the lower 80s Tuesday afternoon. Lows each night in the mid 70s. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... Still have a good amount of uncertainty for Debby's track, but the general idea is that it stalls offshore for awhile before potentially moving inland by Thursday. Dangerous marine conditions continue, while land areas may amass over a foot of rain in some spots, particularly in the Grand Strand area. Go to weather.gov/media/ilm/LatestBriefing.pdf for more details on Debby's expected impacts. This briefing will be updated by 6 PM EDT this evening. Debby's impacts look to slowly decrease for the local area by late in the work week, but may still have some kind of influence going into the weekend before an upper air pattern in the Great Lakes and northeast finally sweeps it away. How this unfolds will determine more of the specifics in the forecast. Highs in the low-to-mid 80s each day, with lows in the low-to-mid 70s each night. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... Intermittent MVFR cigs near the coast and potentially IFR cigs inland through sunrise with moist low levels and light winds. May see MVFR vsbys at I-95 terminals for a few hours near dawn. Predominantly VFR this morning with widespread MVFR ceilings moving in from the south around midday/early afternoon, impacting coastal terminals by 18z and inland SE NC by 0z. Ceilings may lower to 800-1200 ft range towards end of TAF period. Expect lightning activity to be limited today with meager instability. Shower coverage increases late this morning through the afternoon, before activity briefly dwindles this evening. Winds generally 10 kts or less out of the south- southeast. Extended Outlook...MVFR/IFR expected as Tropical Storm Debby could bring very heavy rain through at least mid week. && .MARINE... Through Monday...Most of the period characterized by southerly winds brought by the Bermuda High. Backing will spread across southern waters on Monday as the outer isobars of Debby encroach. The 3-4ft wind wave will be dominant with a weak southeast swell continuing. Monday Night through Friday...Heavy rain and a few thunderstorms continue through at least Wednesday night, with winds gradually shifting from the SSE to the SE and ESE. Debby's center starts its very slow approach Tuesday, which causes an increase in the wind. The center doesn't finally approach until Wednesday night into Thursday, per the latest forecast. This would bring tropical-storm- force winds to the coastal waters. Seas at 3-5 ft initially jump up to 6-8 ft at the coast and 10-11 ft away from the coast at the height of this event. Winds and seas start to decrease Friday as the storm finally starts to leave the area, but significant impacts are still expected. && .TIDES/COASTAL FLOODING... Other - Rip Currents: There is a moderate risk of rip currents for all beaches Monday, becoming a high risk Tuesday through Thursday. A High Surf Advisory may be needed mid to late week. && .ILM WATCHES/WARNINGS/ADVISORIES... NC...None. SC...None. MARINE...None. && $$ SYNOPSIS...ILM UPDATE...VAO NEAR TERM...MBB SHORT TERM...IGB LONG TERM...IGB AVIATION...VAO MARINE...MBB/IGB TIDES/COASTAL FLOODING...