textproduct: NWS Wilmington

WHAT HAS CHANGED

Aviation section updated for 00Z TAFs.

KEY MESSAGES

1) Dry and seasonable through Saturday.

2) Unsettled weather expected to commence on Sunday and continue at least through Tuesday.

DISCUSSION

KEY MESSAGE 1... Dry and seasonable through Saturday.

Through Saturday, mid-upper troughing will gradually shift eastward, followed by a shortwave ridge. Abundant dry air and subsidence through the mid-upper troposphere will maintain mainly dry conditions across the area while a front remains stalled to the south. While an isolated brief shower cannot be ruled out along the sea breeze, the vast majority of the region will stay dry given this setup.

Temperatures are expected to remain near normal during this period with highs mainly in the low 90s and lows in the upper 60s to low 70s.

KEY MESSAGE 2... Unsettled weather expected to commence on Sunday and continue at least through Tuesday.

As an abnormally strong mid-upper trough slides southeastward out of the Midwest, moisture will increase significantly on Sunday as the stalled front lifts back northward. Precipitable water values are forecast to rise to 2.2-2.5", which is 120-140% of normal for this time of year. Although the evolution of this trough (e.g., whether it closes off into a closed low) carries low confidence, its progression is expected to be slow, which results in an extended period of unsettled weather that lasts from Sunday through Tuesday. Daily shower and storm coverage is likely to be enhanced above normal summertime levels in this setup due to the abundant moisture in the atmosphere, but the degree of coverage is dependent on the evolution and positioning of the trough. Thus, while the potential for beneficial rainfall is present, the range of observed amounts will be very wide with some areas picking up little to no rain while others could see multiple inches within an hour or two.

Guidance tools generally agree that the troughing will weaken from Wednesday onward with more typical isolated to widely scattered showers and storms taking over.

AVIATION /00Z FRIDAY THROUGH TUESDAY/

Widespread VFR to start off the 00Z TAF period. Plenty of dry air and subsidence will make for a clear night. Although calm winds all night may be able to produce shallow ground fog in areas which have seen rain over the last 7 days, the conditions above the ground are unfavorable for fog to grow vertically. There is still a low chance for fog, mainly for the SC terminals, but not confident enough to include in the TAFs for now.

Little to no wind in the boundary layer will result in light and variable winds between 12-18Z tomorrow except for steady onshore winds commencing at the coastal terminals around midday with the passage of the sea breeze.

Extended Forecast... VFR likely into Saturday. At least transient MVFR to IFR restrictions become likely between Sunday and Tuesday as a slow-moving disturbance brings abundant moisture and scattered to widespread showers and storms back into the picture.

MARINE

Through Monday... Expect winds to subside to 10 kts or less this afternoon as the pressure gradient weakens. Light and variable winds become light southeasterly by late Friday afternoon as weak high pressure passes north of the area. Southeast winds gradually increase on Saturday and veer to southerly over Saturday night as a stalled front lifts back to the coast. Winds increase considerably on Sunday as the pressure gradient tightens and the front lifts inland, resulting in breezy south winds with gusts likely to pass SCA criteria on Sunday and possibly into Monday.

Weak winds will yield benign seas between 1-3 ft through Saturday night. Seas rapidly increase to 4-6 ft as winds increase on Sunday and these continue into Monday before relaxing gradually on Monday night.

ILM WATCHES/WARNINGS/ADVISORIES

NC...Coastal Flood Advisory from 10 PM this evening to 1 AM EDT Friday for NCZ107. SC...None. MARINE...None.