Key MESSAGE 1, Zonal flow remains in place over eastern NC, forecast to eventually give way to strong ridging over the eastern CONUS later this week. At the surface, persistent wedge of high pressure continues to linger over much of the mid- Atlantic and Carolinas, but low level clouds have begun to erode and consequently temperatures have rebounded inland.
Main focus this afternoon and tonight will be sea fog, especially over the cooler waters along the Northern Outer Banks where warmer airmass will continue to linger. Regional webcams show low visibilities are persisting primarily over offshore waters this afternoon while land-based areas are clearing out, but expecting a return of lower visibilities after sunset as winds weaken once again, bleeding into the Albemarle Peninsula. Model guidance has handled current visibility trends rather poorly so overall confidence is lower than average.
Farther inland, with calm winds and saturated low- levels more widespread fog is forecast to develop overnight and linger through the morning commute Wed.
KEY MESSAGE 2, An anomalously strong ridge will set up over the southeast US tomorrow and remain in place into early next week. This will bring near record temperatures possible for some inland zones some afternoons, especially Thursday through this weekend (see Climate Section below). Highs will reach the upper 70s/low 80s generally along and west of US 17, and upper 60s/low 70s closer to the coast. The immediate coast will remain cooler due to very cold ocean/sound temperatures. A few isolated showers may develop at times in the sea breeze circulation, but overall expect strong subsidence and mostly dry conditions to persist until at least late this weekend.
00z Wednesday through Sunday Confidence has increased for widespread dense fog tonight across land and marine zones. Flight cats are expected to remain VFR until around midnight or shortly after when VIS and CIGs will tank quickly. Vis of 1/4 mile or less is expected to engulf most of the area (except between Cape Hatteras and Cape Lookout) by around 07/08Z and stay socked in until mid-morning. Stubborn sea fog may cause areas north of Cape Hatteras and south of Cape Lookout to hang on to sub-MVFR VIS through the day. Cigs will scatter out by mid-morning as well with a mixture of SCT mid and high clouds through the day. Winds will go calm tonight, becoming SW at 5-10 kt tomorrow.
Main concern this afternoon remains sea fog which webcams show lingering over the offshore waters primarily north of Oregon Inlet. Visibilities will likely oscillate between poor and fair through the afternoon, but with light winds think poor will be more predominant and likely under a mile at times. For that reason, the DFA has been extended for northern waters until 00z tonight. Further expansion may be needed tonight as winds weaken but moist airmass remains and Td depressions remain near zero. Dfas may need to be extended back over soundside waters after sunset.
Weakening northerly winds this afternoon will trend light and variable early this evening before light southerly flow eventually develops tonight. Light S/SW flow 5-10 kts will increase to around 10-15 kt tomorrow afternoon with increasing thermal gradient. Despite the light winds, small craft seas will linger over much of the coastal waters north of Ocracoke through tomorrow, ranging from 4-6 ft.
Outlook: Pleasant boating conditions are expected for the rest of the week and into this weekend. Winds generally be 10-20 kts out of the S/SW as high pressure remains offshore.
Nc, none. Marine, small craft advisory until 7 am EST Wednesday for amz150. Small craft advisory until 7 pm EST Wednesday for amz152-154.
