


Area Forecast Discussion
Issued by NWS Wilmington, NC
Issued by NWS Wilmington, NC
336 FXUS62 KILM 031756 AFDILM Area Forecast Discussion National Weather Service Wilmington NC 156 PM EDT Sun Aug 3 2025 .SYNOPSIS... A cold front will remain stalled to our south through at least Wednesday. Temperatures and humidity will remain below normal for August today and Monday, but should begin to creep back toward normal later in the week. Periods of isolated to scattered showers and thunderstorms may become more widespread late in the week. && .NEAR TERM /THROUGH MONDAY/... Over the next few hours, a few light showers may work their way through the dry air in place over the southern Grand Strand. These echoes have not been uniformly precipitating in CHS`s area and their battle against the dry air to the north is a losing one. If any rain manages to fight through the expansive dry layer, expect only a brief drizzle. High pressure continues to dominate the Carolinas, bringing below normal temperatures and a refreshing reprieve from the multi-month trend of humidity and sweltering high temperatures. With very little change in the position and strength of the high tonight, expect a similar forecast to last night. Lows in the low to mid 60s with help from a light NE wind. Mid-level clouds tonight will signal the gradual return of moisture north of the stalled boundary to our south. With this, there will not be quite as much sunshine on Monday morning, but cool temperatures and crisp dew points should make for a fantastic start to the work week. Trends for controlling high pressure to our north will be weaker and a little farther north through Monday afternoon. Any showers that develop should remain light as the depth of saturations remains limited by dry air at the surface. Coastal northeastern SC appears to have the best chance of a few afternoon showers, but isentropic lift along the northern fringe of this precip shield has been weak, so confidence remains low. Most of the precip has remained well inland, east of the main trough axis, and this axis remains generally stationary on Monday. Highs a touch warmer than Sunday: low to mid 80s. Early clouds and precip chances will heavily influence these temperatures (i.e. upper 70s are not out of the question for portions of the area that see rain). && .SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/... The key players in the weather pattern through this period will be a stalled front south of the area, high pressure shifting eastward across central Quebec keeping a "cold" air damming wedge in place east of the Appalachians, and a sharpening mid-upper trough axis centered over the Mississippi River. While the surface front should hold near the Florida-Georgia border vicinity through the period, the flow aloft will back to southwesterly as the trough west of the area exerts an increasing influence on our weather. This will promote a return of moisture northward over the surface wedge and result in pwats returning to around and perhaps above 2" on Tuesday. However, with the surface front so far south, it is questionable how much precip we may see during this period. While guidance is depicting multiple shortwave impulses embedded in the flow over Monday night into Tuesday, the placement of the trough axis should keep these impulses and their associated precip mainly west of the forecast area. On Tuesday, the trough axis slowly drifts eastward and should bring increasing rain chances to our southern and western zones during the afternoon and evening, primarily in the form of showers with isolated thunderstorms. During Tuesday night, yet another shortwave is depicted which may bring enhanced coverage of showers and isolated storms, but guidance currently keeps the main precip zone just far enough west. However, this will depend highly on the trough axis placement and magnitude, so rain chances may increase for the overnight period in future updates. Temperatures will remain near to slightly below normal under this "cold" air damming setup, with lows in the upper 60s to low 70s away from the immediate coast and Tuesday`s highs in the mid-upper 80s. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... Confidence decreases going into the long-term period as the aforementioned trough gets squeezed between a strong mid-upper anticyclone over the Desert Southwest and a subtropical high over the Atlantic, which will be retrograding westward. The trough is expected to become increasingly sharp and may close off into a weak closed low somewhere east of the Mississippi River and west of the Appalachians. Deep-layer south-southwesterly flow east of this trough/low will keep plenty of moisture aloft in place through the latter half of the week and weekend while that surface high pressure wedge on the east side of the Appalachians continues to impart light north to northeast winds. The stalled front offshore will waver and may drift back towards the coast depending on the evolution of the mid-level trough. In addition, passing shortwave impulses aloft should bring periodic chances for showers and storms, but this will depend on their timing and placement. Something to note here is surface winds are expected to remain light northerly or northeasterly through most of this period, keeping temperatures near- to below-normal in the mid-upper 80s and keeping dew points at more "comfortable" levels in the upper 60s to low 70s instead of the mid-upper 70s seen in July. With air and water temps expected to be near each other this week, the sea breeze should remain generally weak and may not be able to develop anything more than an isolated shower or two at the worst. In addition, while the surface wedge is not terribly strong, convective inhibition associated with this wedge should keep daytime pop-up activity very isolated unless a well-timed shortwave can bring rising motion into play at the right time during the afternoon, or the stalled front drifts close enough to the coast. Therefore, while NBM-based PoPs are in the likely range daily across eastern areas, these may need to come down in future updates as the surface pattern is just not as supportive for summertime afternoon pop-up convection in the typically- favored zones (sea breeze and Piedmont trough), which would normally become quite active in this setup if the high pressure wedge was not in place. Instead, favored times for showers and storms will more likely depend on passing shortwaves aloft and may occur during atypical times, such as overnight or in the early morning. Something else to keep an eye on is the GFS`s insistence on a tropical or subtropical low taking shape along the stalled front and nearing the NC coast around or on August 8, a solution that has been shown for the last few runs, but generally lacks support from other global guidance and their ensemble systems. Nevertheless, the 12Z CMC is showing a shift towards the GFS solution and NHC has recently outlooked a 20% chance for tropical cyclone formation of the coast of the Carolinas for mid-late week. Thus, this is a low confidence scenario, but one that will be monitored closely for changes in future model runs. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... Confidence is High in VFR conditions through Monday. With moisture gradually working its way northward on Monday and high pressure weakening, a few showers will be possible during the late morning and afternoon. If any showers develop prior to the end of this forecast period, it would be near the Grand Strand. Dry air near the surface should keep restrictions to MVFR at the worst, likely too light to even bring terminals below VFR. Extended Outlook... Isolated showers and brief MVFR restrictions are possible on Monday afternoon. Rain chances increase on Tuesday with returning moisture, but confidence remains low at this time. Rain chances increase later this week and so too will the chance for widespread restrictions. && .MARINE... Through Monday... Northeast winds continue to power through the nearshore waters. High pressure to our north and low pressure to our southeast have separated enough to see winds return to 15-20 knots and seas 3-5 feet. This has been enough to lower the SCA, but is by no means comfortable for small craft. An isolated gust to 25 knots is still possible for the NC nearshore waters. Improvement will be gradual, but consistent overnight. High pressure over the northeast will weaken through the day on Monday. Seas 3-5 feet tonight, settling to 2-4 feet on Monday. Monday night through Friday... A surface high pressure wedge is expected to dominate the weather through the period, with east to northeast winds through the first half of the week tending towards northeast and eventually northerly by Friday. Speeds should hold around 10-15 kts unless a tropical or subtropical low forms along the stalled front and approaches the coast near the end of the week (currently a very-low confidence scenario). Seas generally hold around 2-4 ft, with east-northeasterly swells being the primary contributor with a period of 8-9 sec, followed by weak wind waves and a subtle southeasterly swell of 1-2 ft with a period of 7-8 sec. && .ILM WATCHES/WARNINGS/ADVISORIES... NC...Beach Hazards Statement until 8 PM EDT this evening for NCZ106- 108. Coastal Flood Advisory from 5 PM this afternoon to 8 PM EDT this evening for NCZ107. SC...Beach Hazards Statement until 8 PM EDT this evening for SCZ056. MARINE...None. && $$ SYNOPSIS...ILM NEAR TERM...21 SHORT TERM...ABW LONG TERM...ABW AVIATION...21 MARINE...21/ABW