textproduct: NWS Wilmington

WHAT HAS CHANGED

Slow moving convection continues to result in a few Flood Advisories across inland portions of the forecast area. Expect this convection to weaken over the next couple hours with the loss of heating. In the meantime the slow movement coupled with some mergers and boundary interactions will support pockets of heavy rainfall. Made some adjustments to the forecast to account for these trends. Otherwise, the aviation discussion was updated for the 00Z TAFs.

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 /21Z SATURDAY THROUGH THURSDAY/

VFR conditions will prevail through the evening outside of any convection. KFLO has the best chances during the next couple hours. During the overnight and early morning hours KFLO/KLBT have the best shot at VSBY/CIG restrictions. Otherwise, showers and thunderstorms from offshore nocturnal storms may approach the coastal terminals generally after 08-10Z. KILM has the better chances at brief restrictions resulting from these SHRA/TSRA during this time compared to KCRE/KMYR.

Extended Forecast...There is moderate potential for MVFR to IFR conditions in low clouds and fog each morning through mid next week. The coverage of SHRA/TSRA is expected to be lower Monday through Thursday with a drier air-mass in place during that time.

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.