Marine Weather and Tide Forecast for Swansboro, NC

KEY MESSAGES
1) Seasonable and mostly dry through Saturday.

2) Warm front/coastal trough moves through Sunday morning, with above average rain chances Sunday into midweek.

Marine: SCA conditions likely to develop Sunday into Monday.

DISCUSSION
KEY MESSAGE 1...No real changes to forecast thinking through Saturday as high pressure will gradually build overhead today bringing light and variable winds to the area before pushing offshore tonight. Could see a few isolated sea breeze showers this afternoon and again on Sat afternoon but confidence is too low to include any mentionable PoPs either day given ample dry air and subsidence over ENC. Otherwise seasonable temps forecast today as highs reach the upper 80s to low 90s inland, and mid 80s along the coast. Lows tonight get into the upper 60s to 70s.
Southerly onshore flow begins in earnest on Sat allowing atmospheric profile to gradually moisten. As a result while we likely wont see much in the way of rain on Sat, we should see an increase in cloud cover, which will keep Highs in the upper 80s to low 90s inland, mid 80s along the coast once again.

KEY MESSAGE 2...No real changes to forecast thinking as ENC once again enters into a period of unsettled weather starting on Sunday.
An upper trough will be deepening over the Ohio Valley Sun morning as it moves towards the Eastern Seaboard, while at the surface an associated closed low is expected to traverse the Great Lakes region. As these features move east, they will encounter the Bermuda high which is expected to stall this upper trough, surface low, and its associated fronts before they reach the Eastern Seaboard. While the upper trough stalls, embedded shortwaves rounding the base of the trough are forecast to advect into the region Sun through at least Mon/Tue. These features, in addition to the sea breeze each afternoon/evening, will be the main forcing present for a notable increase in precip chances.

There will be two areas of focus for shower and thunderstorm activity on Sunday. The first will be Sun morning along and behind a N'ward moving warm front/coastal trough with much of the activity occuring near and east of Hwy 17. The second will be in the afternoon/evening with shower and thunderstorm activity coming in from the west associated with the stalled upper trough. Cloud cover will play a big role in how high instability can truly get, but with the dewpoints rising there should be enough instability entering the region for 1000-2000 J/kg of MLCAPE Sunday. While shear is not too impressive with the unidirectional SE flow, the combination of long, skinny CAPEs, PWATs over 2", and slow storm motions could result in heavy rainfall rates and wet microbursts where storms develop. Will note shower and thunderstorm activity will be scattered in nature on Sun so showers and storms will be "hit or miss".

Monday the trough is still stalled to our west, but is just a little bit closer allowing for weak height falls and weak embedded shortwaves to move through aloft. This better forcing, paired with another day of long skinny CAPEs and PWATs north of 2" brings high precip chances with heavy rainfall rates and a low end wet microburst threat and slow storm motion vectors. The better forcing likely brings with it better coverage of precip. All this brings flash flooding concerns to mind, especially with how much rain has been observed in many locations in the past 1-2 weeks. We are currently in a Marginal (level 1/5) Excessive Rain Outlook for Sunday. What prevents it from being higher is likely the uncertainty on instability with antecedent cloud cover and the lack of substantial ground-level forcing. With high temps forecast to only be in the low to mid 80s Sunday, the sea breeze may be weak in nature.

Beyond Monday, the trough/low is still expected to linger to our west until eventually it gets picked up and shifted to our north by another trough moving through the Great Lakes region. As a result, daily elevated precip chances continue through mid-week with a low end risk for flash flooding.

AVIATION /00Z SATURDAY THROUGH WEDNESDAY/
Pred VFR conditions expected through the TAF period with mainly diurnal Cu through peak heating. Another night with calm winds and clear skies allowing for good radiational cooling but HRRR and REFS probs for vsbys less than 5SM continue to show less than 15 percent during the pre-dawn hours. Given there hasn't been fog the past couple of nights it likely will not materialize. S to SW winds will be a bit stronger Saturday afternoon with gusts around 15-20 kt possible.

Outlook (Saturday night through Wednesday): It remains dry with primarily VFR conditions forecast through Sat evening as high pres remains offshore. Periods of sub-VFR may develop Sun into early next week as ENC enters into a more unsettled period of weather with daily chances for showers and thunderstorms with a stalled upper trough off to the west. Precip chances and thus the threat for sub- VFR conditions look to decrease beyond Wed.

MARINE
Benign boating conditions continue across our waters today as latest obs show widespread 5-10 kt winds and 2-3 ft seas across our waters today. Expect benign conditions to continue through Saturday with winds becoming S'rly as high pressure builds overhead and pushes further offshore on Sat.

Outlook (Saturday night through Wed): Southerly flow continues through Sat night with seas persisting at 2-3 ft. Southerly winds will strengthen Sunday to 15-25 kts with gusts up to 25-30 kts ahead of an approaching front. Seas will also respond building closer to 4-7 ft across the coastal waters bringing an increasing chance of SCA conditions to much of our waters Sun into Mon. In addition to this, increasing chances for showers and thunderstorms will be possible as well starting Sun.
Winds/Seas begin to ease later Mon night into Tue with weak high pressure building overhead and aforementioned front dissipating to the west.

MHX WATCHES/WARNINGS/ADVISORIES
NC...None.
MARINE...None.