textproduct: NWS Wilmington

WHAT HAS CHANGED

Updated Aviation discussion for 12Z TAFs.

KEY MESSAGES

1) Deep tropical moisture in place this week will keep rain chances elevated and maintain the potential for isolated flooding.

DISCUSSION

KEY MESSAGE 1...Deep tropical moisture in place this week will keep rain chances elevated and maintain the potential for isolated flooding.

Not much pattern change through mid-week with southerly low- level flow promoting moisture transport into the Carolinas and upper-level ridging staying offshore. Forcing will be provided by the daily sea breeze, heating, convective outflows, and weak upper-level divergence. Tough to pinpoint exactly where and when it will rain each day, but the expectation is for a typical summertime pattern with higher rain chances inland during the day, while higher over the coast and offshore overnight.

Precipitable water (pwat) exceeds 2" for much of today and Wed and at times is among the highest values recorded at CHS/MHX for those days. The combination of extreme pwat, deep warm cloud layer (13k ft+) and slow storm motion creates a setup perfect for significant rainfall and minor flooding. Multi-day rainfall totals in excess of 5" will be possible in any locations that experience multiple rounds of storm or training storms.

Slightly drier mid-level air works its way north by Thursday, however a sfc boundary in the vicinity will keep rain chances elevated, especially towards the coast. There continues to be model disagreement over how far south the front pushes, but regardless it should be close enough to keep rain chances in the forecast Thu. Better mid-level energy will keep chances of rain around Fri into the weekend, with higher rain chances over southern areas as surface high pressure and drier air try moving in from the north.

AVIATION /12Z TUESDAY THROUGH SATURDAY/

A stray shower is possible at the coastal terminals this morning. Low clouds will gradually lift at inland terminals this morning as low level mixing increases. Widespread IFR will become VFR by late morning or early afternoon. MVFR at the coast will also trend toward VFR by late morning.

Showers and thunderstorms are expected to develop today, primarily inland and just east of I-95. Impacts are likely to occur at inland terminals, but winds just west of south could bring some showers and storms into the ILM vicinity. Maintained a PROB30 for ILM. The sea breeze should keep activity inland at CRE/MYR. Low stratus and some shallow ground fog will be possible at inland sites tonight. Coastal terminals should see enough wind to maintained MVFR.

Extended Forecast... Low stratus or fog will continue through much of this week with the best potential at KFLO and KLBT. Afternoon and evening showers and thunderstorm may develop each day this week: the sea breeze near the coast will keep most of this activity inland through Wednesday, however convective activity shift preferentially toward the coastal airports for Thursday and Friday.

MARINE

Through Tonight... Bermuda high pressure remains dominant feature through tonight. South winds 10-15 knots with gusts around 20 knots will be possible through Wednesday morning. Seas 3-4 feet out to 20 nmi, and 4-6 feet from 20-60 nmi. SSE 7 second swell remains the primary component with a diminishing 1 ft ENE swell. Scattered showers and thunderstorms forecasted over the waters tonight into early Wednesday.

Wednesday through Saturday... Southerly flow Wed through Thu will increase as gradient on the west side of the Bermuda High tightens up. Potential for sustained 15-20 kt, especially beyond 20nm. Front dropping in from the north Thu night into Fri may lead to a period of northeast or east flow to end the week, but confidence in the timing and how far south the front moves before stalling is low. Seas around 4 ft Wed briefly build to 4-5 ft within 20 nm and 5-6 ft 20-60nm late Wed night before flow becomes more westerly, pushing the higher seas farther east. Seas drop to around 4 ft Thu afternoon, settling in the 3-4 ft range for Fri and Sat.

ILM WATCHES/WARNINGS/ADVISORIES

NC...Beach Hazards Statement through this evening for NCZ106-108. SC...Beach Hazards Statement through this evening for SCZ054-056. MARINE...None.