textproduct: NWS Wilmington

WHAT HAS CHANGED

High temperature forecasts have been increased by 1-2 degrees Sunday and Monday.

KEY MESSAGES

1) Multiple surges of Gulf moisture could bring rain to the area Saturday, Sunday, and Monday ahead of the next cold front.

DISCUSSION

KEY MESSAGE 1...Multiple surges of Gulf moisture could bring rain to the area Saturday, Sunday, and Monday ahead of the next cold front.

The first of what appears to be three distinct shortwaves will approach from the west on Saturday, drawing a slug of Gulf moisture northward across the Carolinas. The best overlap between synoptic lift and deep moisture appears to occur between mid morning and early afternoon on Saturday. Even without the benefit of daytime heating lapse rates aloft may be steep enough to bring a few thunderstorms mixed in with the showers. Forecast PoPs range from 40- 50 percent west of I-95 to 60-80 percent along the coast. It's worth noting that the NBM ensemble mean shows more coverage than deterministic GFS/NAM/ECMWF guidance suggests on Saturday.

Shortwave number two arrives from the Gulf late Saturday night into Sunday bringing another round of scattered showers with embedded thunderstorms. Forecast PoPs range from 30 percent west of I-95 to 40-50 percent along the Grand Strand coast.

The final shortwave should arrive on Monday coincident with a surface cold front that should extend from Nova Scotia all the way into northern Mexico. Models are hinting at a late afternoon or early evening frontal passage across the eastern Carolinas with deep moisture and reasonably good upper dynamics present, all factors that support the NBM's 80 PoP.

To summarize, rain chances spread out across three days on the back of measurable rain yesterday won't be enough to end the drought, but should prevent further degradation from occurring over the next one or two weeks. QPF of one-half to one inch is expected through Monday.

AVIATION /06Z FRIDAY THROUGH TUESDAY/

All VFR through the 06Z TAF period. FEW to SCT clouds at 3000-5000 ft continue to sweep through the terminals, but cloud decks will lift over the next few hours. Some fog is settling in across parts of the Piedmont to the north, and may try to reach KFLO and KLBT as we head towards sunrise. Confidence is still too low to include in the TAF at this time.

Whatever fog that forms should erode by 13-14Z at the latest. Light NNE winds at 5 kts will veer to the SE at the coastal terminals by 16-18Z, due to the seabreeze. Winds become more variable inland. Winds calm or become light and variable by sunset, with more cirrus pouring in.

Extended Forecast...VFR should continue through at least Saturday morning. Restrictions become more likely Saturday afternoon, especially at the coast, due to increased rain chances. More widespread unsettled weather expected Sunday and Monday. VFR expected Tuesday.

MARINE

Through Tonight...Moderate breeze out of the NNE will come down towards a gentle breeze by late this afternoon, veering to the east, and then southeast by this evening. Seas currently 2-4 over the coastal waters out 20 nm, 4-5 ft out 60 nm, but come down throughout the day towards 1-2 ft along the coastal waters, 2-4 ft along the offshore waters. Outside of wind waves with 4-7 second periods, look for a 1 ft swell out of the ESE at 9-11 seconds.

Saturday through Tuesday...High pressure over the western Atlantic and low pressure across the Plains should produce a south to southwest synoptic wind across the area Saturday into Sunday. A pair of upper level systems passing across the area will bring scattered to numerous showers and thunderstorms across the area this weekend. Some of the storms may bring briefly stronger wind gusts.

A cold front should approach from the west Monday with another wave of showers and thunderstorms expected to move across the coastal waters. The front itself should move offshore during the evening hours with cooler northerly winds and dry weather building in for late Monday night into Tuesday. Wind speeds behind the front could exceed 20 knots and we'll have to monitor for a possible Small Craft Advisory next week.

ILM WATCHES/WARNINGS/ADVISORIES

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