172 FXUS62 KILM 061943 AFDILM Area Forecast Discussion National Weather Service Wilmington NC 343 PM EDT Mon Sep 6 2021 .SYNOPSIS... Temperatures and humidity will continue to return to normal tomorrow with afternoon showers and storms possible. A series of cold fronts will bring additional rain chances Wednesday and Thursday before the forecast dries out by next weekend. Hurricane Larry continues to stay at sea, but swells will enter local waters this week, creating dangerous rip currents and rough surf at area beaches. && .NEAR TERM /THROUGH TUESDAY NIGHT/... Widely scattered light showers beginning to appear on radar as weak frontal boundary is reaching our CWA boundary. Boundary continues its slow movement through the evening into overnight hours, stalling across the area in a SW-NE orientation into tomorrow. Spotty light showers will continue through overnight with pops generally around 20%. Isolated thunderstorm possible inland NE SC this evening. Depending on front location in the early morning hours, could see patchy fog develop, generally west of front, for a few hours. Lows tonight around 70 degrees. Lingering boundary tomorrow morning will be pushed northward, while starting to wash out, as sea breeze develops in the afternoon. Increased instability tomorrow with CAPE over 1000 J/kg will aid in the development of scattered storms, particularly along sea breeze and the potential boundary in the area. Pops in the 30-40% range for Tuesday afternoon and highs in the upper 80s. Southerly flow continues Tuesday night ahead of a second approaching cold front with low temps again around 70, and another chance for patchy fog. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... Lingering stationary front will dissipate on Wednesday with the remnant environment capable of producing scattered showers and thunderstorms. Best chance of storms should remain inland along the previous trough axis. Highs around 90 with the typical summer-time humidity. Cold front over the southern Appalachians will begin to push southward on Thursday. Deep SW flow will bring ample moisture ahead of the cold front which should produce widespread showers and storms on Thursday into Thursday afternoon. Highs slightly cooler, in the mid to upper 80s due to the widespread cloud cover and cooling air mass. By Thursday evening, there should be some drier air building into the area associated with the digging trough and the passing front. Will see rain chances end quickly from west to east after sunset. Mid to upper 60s return with the cooler and drier air mass filtering toward the coast. && .LONG TERM /FRIDAY THROUGH MONDAY/... Beautiful on Friday behind the front and underneath a cooler upper- trough. Northerly flow should continue to provide cooler air and temperatures in the low to mid 80s across the area. Have held onto a slight chance of showers along the coast as models flirt with the potential for the cold front to stall just off of the SC coastline. Models continue to hint at the development of a coastal low along the SE coast on Friday evening into early Saturday. This low would likely develop along the offshore front and seems to have little to no chance of developing tropical characteristics. Despite this, we could see a good chance of decent rainfall along the coast if the low tracks along the typical wintertime baroclinic zone. Still alot to work out regarding how far offshore this could develop because it will depend greatly on the offshore push of the surface front and the speed at which the mid-level trough axis approaches the central Carolinas. Conclusion at the moment is that the low will develop further offshore and keep us dry for Saturday. The sphere of influence for this low should be fairly small given the surrounding RH environment and therefore, if anyone was to see rain this weekend, it would be confined to the immediate coastal areas. The upper-trough will eventually prevail and a dry air mass will build over the area by Sunday into at least early next week. We will lose our cooler air as solar insolation moderates the overall air mass and mid-level W or NW flow descends over the terrain of the southern Appalachians. Highs should warm to near 90 on Sunday with lower 90s on Monday. Overnight lows in the low or mid 60s. && .AVIATION /20Z MONDAY THROUGH SATURDAY/... A frontal boundary will stay just west of the CWA, with isolated convection possible west of the I95 corridor. An isolated strong storm is possible. Moisture on the increase tonight with a mid cloud ceiling. Extended Outlook...Mainly VFR. Isolated to scattered showers and thunderstorms Tue though Thu could bring brief flight category restrictions. && .MARINE... Through Tuesday Night... Weak front approaches the coast from the northwest late this evening and is expected to linger inland. Southwest winds this evening are still expected to weaken and become variable with front nearby through Tuesday morning. Southerly winds redevelop Tuesday afternoon and night as a previous boundary washes out and a second cold front approaches from the west. Seas around 2 feet tonight and Tuesday will be a on a slow rise beginning Tuesday night as long period swells from Hurricane Larry, which enter the coastal waters tonight, increase into late week. Wednesday through Saturday... Southerly flow increases on Wednesday near a stationary front over the central Carolinas. Meanwhile, swells from distant Larry will increase to near 4-5 feet at 15 seconds. This could easily become dangerous for Small Craft, especially given the near perpendicular wind wave generated by SSW winds. Winds out of the SSW around 10-15 knots on Wednesday evening will veer to westerly by Thursday as a stronger cold front approaches the area and passes offshore by Thursday evening. Northerly flow develops by Friday morning behind the front around 10- 15 knots, becoming NE by Friday afternoon. Swells continue to increase with indications of 5-6 feet around 15 seconds, steepening due to the competing wind directions. Low pressure may begin to develop on Friday night into Saturday along the offshore boundary and this could move into the area, bringing further elevated seas and hazardous Small Craft conditions. Still a lot of uncertainty regarding this disturbance for now. Winds become offshore by Saturday with a drier and cooler air mass settling in for the end of the weekend. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...None. NC...None. MARINE...None. && $$ SYNOPSIS...ILM NEAR TERM...VAO SHORT TERM...21 LONG TERM...21 AVIATION...43 MARINE...VAO/21