textproduct: NWS Wilmington

WHAT HAS CHANGED

No significant changes have been made to forecast thinking.

KEY MESSAGES

1) Scattered showers and thunderstorms along the coast this morning, translating inland this afternoon. Showers and storms remain possible well into next week.

DISCUSSION

KEY MESSAGE 1...Scattered showers and thunderstorms along the coast this morning, translating inland this afternoon. Showers and storms remain possible well into next week.

Unseasonably high levels of moisture will continue across southeast NC and northeast SC through Saturday while a nearly stationary front lingers inland and some mid-level energy impacts the area. This will lead to higher than normal rain chances for much of the period, although rainfall amounts should generally be a few tenths of an inch or less tonight thru Saturday. The most rainfall is likely to be well inland closer to the front, possibly exceeding an inch locally.

An extended period of high precipitable water values and largely uncapped/uninhibited deep instability should yield scattered to numerous showers and thunderstorms each day next week. While perhaps not the best news for those planning weather-sensitive outdoor activities, this is excellent news from a drought/water supply perspective.

The upper air pattern next week should feature a 500 mb ridge centered south of Bermuda and a trough extending from the western Great Lakes southward into the Arklatex region. Sustained deep southwest flow originating from the Gulf should bring a stream of 1.8 to 2.0 inch precipitable water across the Carolinas. That's about 0.5 inches above normal at the KCHS upper air site and above the 90th percentile for late May. With the offshore ridge remaining far enough east, the capping inversion that can sometimes inhibit warm season convection should be absent except perhaps along the coast Tuesday into Wednesday.

As has become typical, NBM PoPs are higher than GFS or ECMWF MOS values by about 20 percent each day. Even following the lower MOS guidance numbers, scattered to numerous showers and thunderstorms are expected almost each day next week. Bulk- shear values don't appear significant, at least at this time range, so convection is likely to be garden- variety single cells capable of producing locally heavy rain, but not organized severe weather. Forecast seven day rainfall totals range from 1-1.5 inches along the coast to as much as 3 inches along and west of I-95.

AVIATION /18Z FRIDAY THROUGH WEDNESDAY/

High confidence in mainly VFR conditions thru much of the 18Z TAF period. However, do expect periodic restrictions possibly down to IFR or lower levels from low clouds and possible fog (mainly at KLBT/KFLO late tonight into early Sat) as well as from showers/storms (mainly at KLBT/KFLO).

Extended Forecast...Moderate to high confidence in at least MVFR cigs (and to a lesser extent vsbys) each morning (mainly in the 08z- 12z timeframe at KLBT/KFLO), as well as from showers/storms (mainly in the aftn/eve).

MARINE

Through Saturday...High confidence in mainly benign, summer-like conditions due to prevailing Bermuda high pressure. Southerly winds will mostly be 10-15 kt or less, generally highest eastern portions near the Gulf Stream and closer to the coast due to the aftn/eve sea breeze. Waves will continue to be dominated by 2-5 foot, ~8 second southeast swells.

Saturday night through Wednesday...Generally light southwesterly winds are expected the first half of next week between high pressure over the Western Atlantic and lower pressures along a front stalled to our north and west. Daytime seabreezes and nighttime landbreezes will add to nearshore wind variability, as will scattered showers and thunderstorms. This will be a very summerlike pattern with a humid tropical airmass in place.

Seas should mainly consist of two 8-second swell groups, one from the southeast and a smaller one from the east. With a small wind chop added into the mix, combined seas should average 3-4 feet through the period, a little over a foot larger than is typical for this time of year.

ILM WATCHES/WARNINGS/ADVISORIES

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