Key MESSAGE 1, Strong high pressure building into the Mid-Atlantic and low pressure well off the SE coast will result in a period of breezy to strong NE winds through early next week with strongest winds along the coast, especially south of Cape Hatteras where gradients will be tightest. This, combined with upcoming King Tide cycle lead to additional minor coastal impacts (coastal flooding and rough surf).
For Hatteras Island, seas offshore have increased yet again to 8-10 ft, and these higher seas will continue today, and only very slowly subside through the coming week, and likely remain above 6 ft through mid week. Guidance available in our system continues to be underdone so went with NBM (highest available) and manually bumped up values for waters N of Cape Hatteras. This will continue to bring the threat of ocean overwash to vulnerable areas where the dune structure has been compromised, especially around the times of high tide. For ocean-side: high tide is between 1830-1930EDT this evening, and 0700-0800EDT SUN. Soundside high tides lag from 2 to 3 hours behind the oceanside tides. The National Parks Service and NCDOT have reported substantial beach erosion from south Nags Head to Buxton, along with significant overwash occurring on side streets in Rodanthe. Due to hazardous road conditions and flooding, NC-12 remains closed from the Marc Basnight Bridge to Rodanthe.
The region is also entering a King Tide cycle this weekend that will build and peak early to mid next week. With a trend in higher seas coinciding with the building tides next week, coastal flooding will be likely well into next week. Even with winds diminishing by mid week, "sunny day" coastal flooding across much of the tidal regions of ENC around times of high tide will continue through mid week. The areas most susceptible to street flooding will be low lying areas along the Neuse and Bay rivers as well as Downeast Carteret County to North Topsail Beach which has already been seen during the last two morning's high tides. The morning high tide will be the highest of the daily tides this weekend and next week with the King Tide peaking TUE and Wed.
Have extended the coastal flood advisories into WED afternoon, with King Tides lasting through mid week. There is still potential that the headlines for TUE and WED may need to be upgraded to coastal flood warnings. Will wait for this decision after we see what SUN and MON bring. In addition, if seas increase any further than currently forecast, a period of coastal flood warnings may be needed for parts of the OBX, and will need to monitor trends.
KEY MESSAGE 2, POckets of moisture continue to be squeezed between the inland high and offshore low. Though almost all guidance keeps the bulk of precip activity off the coast and perhaps skirting OBX, some light returns are evident on KMHX radar this afternoon. Have added a 15-19% chance for portions of the Inner Banks this afternoon into this evening. Pleasantly cooler and drier air mass will remain with us through much of the extended period with near average highs, to slightly below avg lows, esp mid week when high pres builds and good radiational cooling yet again sets up with lows well down into the 40s with some 30s again possible. Maximum temperatures through the period are expected to remain in the mid 60s (OBX) to lower 70s range.
18z Saturday through Thursday Primarily VFR conditions forecast across all terminals through the period despite some diurnal STCU around FL040. Gradient tightens further today with 10-15 kt NE'rly winds and gusts up around 20 kts at times across ENC through the day.Steady NE winds tonight at 5-10 kts inland and 10-20 kts along the immediate coast and OBX will keep the fog threat low.
Outlook (Sunday through Wednesday): Generally, expect VFR conditions to continue through the next several days with strong high pressure building in from the north. However, coastal sections could see MVFR STCU at times. Breezy NE winds are expected to continue into early next week.
High pressure will build in from the north will act to tighten the pressure gradients across the region with NE winds increasing to 15-20 kt with gust cont 25-30 kt. Gradient will strengthen back again Sunday/Sunday Night, and have issued new Gales for the offshore waters south of C Hatteras. Nearshore waters should remain in the SCA range, as well as the sounds and Alligator/Neuse river, before gradient begins to diminish early next week.
Outlook (Sunday through Wednesday): Have inc seas during the mid week period, as AIFS/NBM seas have trended higher with latest 24/00Z model suite. Should therefore see SCA conditions extending into at least mid week for all coastal waters zones despite high pres building in and bringing a diminishing trend in winds into mid week.
Nc, coastal flood advisory until 2 pm EDT Wednesday for ncz094- 194>196-199-203>205. Beach hazards statement until 8 pm EDT this evening for ncz196- 203>205. High surf advisory until midnight EDT tonight for ncz203-205. Marine, small craft advisory from 8 pm this evening to 2 am EDT Monday for amz131-230-231. Small craft advisory until 4 pm EDT Monday for amz135. Small craft advisory until 6 am EDT Monday for amz137. Small craft advisory until 3 am EDT Saturday for amz150-152- 154-156-158. Gale warning from 8 pm this evening to 2 pm EDT Sunday for amz184. Gale warning until 1 am EDT Monday for amz186-188.
