textproduct: NWS Wilmington

SYNOPSIS

Dry high pressure and near seasonable weather arrive today following the passage of a cold front. Another frontal system will affect the area later this week with much cooler weather expected by the end of the week.

NEAR TERM /THROUGH TONIGHT/

Patchy fog and low clouds will accompany a cold front that is working its way southward across the region early this morning. The slow progression of the front will dictate low temperatures. A gradient of lows from mid 50s over SC and lower 50s over the northern part of our area.

High pressure builds behind a cold front on Sunday. Cooler and drier air expected on Sunday; highs in the upper 60s over southeastern NC and lower 70s in northeastern SC. After a mix of patchy fog and low clouds this morning, sunshine should dominate the late morning and afternoon. Clear skies and dry air tonight should allow things to cool off quite nicely. Lower 40s inland, mid 40s at the coast.

SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/

Seasonable and dry to start the work week as high pressure to the northwest migrates east during the day. Northeast flow will keep highs near to slightly below normal under sunny skies. High clouds will start to increase late in the day ahead of the mid-week system, but will have limited impact locally. Weak coastal trough develops Mon night into Tue as the high slips off the coast, but the progressive nature of the flow aloft keeps the high moving, preventing any real wedge development. Trough moves onshore around daybreak and in effect becomes a warm front as southerly flow sets up.

Warm, moist southerly flow Tue pushes temperatures well above normal. Weak surface based instability and increased moisture below 8k ft may lead to some shower development during the day, although instability is very weak, SBCAPE struggles to hit 200 J/kg, and subsidence/dry air above 700mb will keep any showers that develop under 5k ft in total depth. Not a recipe for much if any rainfall. Somewhat better rain chances Tue night as weak front moves into the area then stalls early Wed as it ends up parallel to the flow aloft. Limited dynamics, lingering mid-level dry air and lack of instability will keep coverage in the scattered realm, with best chances west of I-95 in the vicinity of the boundary.

LONG TERM /WEDNESDAY THROUGH SATURDAY/

Front stalled in the region Wed morning lingers into the evening, with deep moisture and increasing surface instability across the local area. Best chances for rain this week will be on Wed given the environment, the weak convergence along the front and modest divergence aloft. Front remains west of the area Wed keeping the region in the warm sector with temperatures well above normal. Northern stream shortwave moving through the larger 5h trough later Wed helps kick the stalled front in the region offshore Wed night night into Thu. The kicking shortwave also send a surge of cold air into the region Wed night, causing temperatures to tumble for Thanksgiving. Lows Wed night will end up near to above normal, but aided by wind/mixing. Strong cold advection will keep highs well below normal Thu with another shot of cold air Thu night into Fri ensuring the week ends dry, but with temperatures well below normal.

AVIATION /06Z SUNDAY THROUGH THURSDAY/

High confidence in restrictions persisting through the current 6 hour TAF period. Lower confidence regarding patchy fog and the potential for VIS restrictions, but CIG restrictions in LIFR or VLIFR will supersede VIS (CIGs less than 800 feet in most cases).

Low clouds disperse this morning and give way to mostly clear skies this afternoon. VFR developing after 13Z and continuing through tonight.

Extended Forecast... VFR outside of some morning fog during the middle of the week. The next chance for rain arrives Wednesday and Thursday with a cold front.

MARINE

Through Tonight... Northerly winds follow a cold front this morning. Cold air advection will be gradual and unlikely to promote the typical level of mixing we would expect with a late fall cold front. Winds begin to increase late tonight as an area of high pressure follows a secondary cold front offshore. Northeast winds increase to 10-15 knots for a brief period late tonight with gusts to 20 knots. Seas 2-3 feet this morning, decreasing to 1-2 feet this afternoon and 2-3 again late tonight.

Monday through Thursday... Northerly flow Mon turns onshore Mon night into Tue as coastal trough develops. Trough lifts northwest Tue morning with southerly flow continuing through Wed. Strong cold advection Wed night and Thu following the passage of a cold front results in strong offshore flow on Thanksgiving. Not much in the way of a pressure gradient Mon through Wed which will keep speeds under 15 kt. Gradient starts to tighten up late Wed or Wed night as the front approaches increasing southerly flow to 20 kt just prior to the frontal passage. Strongest winds will be Wed night and Thu as high pressure builds in. Brief period of 20-25 kt possible late Wed night and Thu which may require a brief duration SCA. Seas 2-3 ft for much of the period, building briefly to 3-4 ft Wed night before the strong offshore flow knocks seas back to 2-3 ft Thu. Wind wave will be dominant, first from the northeast then shifting around to south-southeast later Tue before going back to northerly Thu.

ILM WATCHES/WARNINGS/ADVISORIES

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