textproduct: NWS Wilmington

WHAT HAS CHANGED

Discussions updated. Another round of scattered showers and storms appears likely near the coast late tonight into Sunday morning.

KEY MESSAGES

1) Unsettled weather is expected through the weekend with scattered showers and thunderstorms and heavy rainfall at times.

2) Heat and humidity will return during the upcoming week.

DISCUSSION

KEY MESSAGE 1...Unsettled weather is expected through the weekend with scattered showers and thunderstorms and heavy rainfall at times.

Mid-upper troughing over the eastern US will gradually weaken and lift away over the next day while upper-level high pressure builds eastward in its place. Near the surface, a stalled front will remain nearby or over the area and keep unsettled weather in the picture through Sunday. Guidance tools suggest scattered heavy showers storms this afternoon into this evening across inland areas, where greater sunshine is occurring. Another round of coastal showers and storms also appears increasingly likely late tonight into Sunday morning. With precipitable water values near 2 inches, rainfall rates of 1-2"/hr can easily occur in a slow-moving thunderstorm. Thus, heavy rainfall capable of producing localized flooding is the primary concern, especially if storms end up backbuilding over the same area.

KEY MESSAGE 2...Heat and humidity will return during the upcoming week.

As upper-level high pressure builds eastward early next week, temperatures will rise above normal and shower/thunderstorm chances will decrease to below seasonal norms. With the core of the high pressure center shifting overhead by midweek, expect well-above normal highs in the middle to potentially upper 90s. Heat Advisory criteria may be reached in some areas between Wednesday and Friday, although enough dry air in the lower atmosphere may be able to keep heat indices from reaching 105F or greater across much of the area. Regardless of whether a Heat Advisory is needed, a period of mostly sunny, dry, and abnormally hot conditions (with heat indices of 100F or higher) is becoming more likely.

AVIATION /18Z SATURDAY THROUGH THURSDAY/

VFR conditions exist across all terminals at this point, although transient MVFR cigs may still occur as daytime cumulus continue to form and scattered showers and storms develop across the inland terminals. Confidence is too low at the immediate coast for any impactful showers, but the potential is still just high enough at KILM to maintain a PROB30 there. Otherwise, expect VFR to prevail outside of any passing showers into the first half of tonight. Guidance seems bullish on the potential for fog and low stratus at inland terminals tonight, especially given the continuation of passing high-level cloudiness which prevented restrictions from developing last night. Nevertheless, given the moist conditions and lack of winds, just enough thinning or breaks in the high cirrus can still result in MVFR to LIFR restrictions late tonight into early tomorrow morning. Near the coast, scattered showers and thunderstorms are possible once again, with passing restrictions possible. VFR should return by noon, although this will depend on the extent of fog and low stratus at sunrise.

Extended Forecast...There is moderate potential for MVFR to IFR conditions in low clouds and fog each morning through mid next week. Scattered showers and thunderstorms are possible late tonight through Sunday, with little to no activity expected Monday through Thursday.

MARINE

Through Wednesday... Light east to southeast flow is in place as a stalled front remains inland of the coast with high pressure north of the area. As this front washes out and surface high pressure moves offshore early in the new week, a return of south to southwesterly winds at 5-10 kts is expected. Seas are expected to run 1-2 ft in the 0-20nmi zones and 2-3 ft in the 20-60nmi zones primarily driven by east-southeast 8-9 sec swells. Wind waves of 1 ft or less will continue in tandem with the daytime increase in winds. A longer period swell of 11-12 sec should reach the Southeast coast over Tuesday night into Wednesday, bringing seas into the 2-3 ft range in the 0-20nmi zones and 3-4 ft in the 20-60nmi zones.

CLIMATE

Wilmington, NC is currently matching its hottest summer on record. The average temperature (the simple average of each day's high and low temps) is currently in line with 2011 and 2010 as of the official daily climate report from August 28.

#1 2026 81.8 deg F (with three days left) #2 2011 81.8 deg F #3 2010 81.8 deg F #4 2016 81.4 deg F #5 2022 81.1 deg F

Continuous temperature records began in Wilmington in 1874.

ILM WATCHES/WARNINGS/ADVISORIES

NC...None. SC...None. MARINE...None.