Marine Weather and Tide Forecast for North Topsail Beach, NC

KEY MESSAGES
1) An Arctic cold front arrives Saturday. A Cold Weather Advisory will be needed Saturday night.

DISCUSSION
KEY MESSAGE 1...An Arctic cold front arrives Saturday. A Cold Weather Advisory will be needed Saturday night.

KEY MESSAGE 1 DESCRIPTION...
One final jet max will rotate around the southern periphery on the through in the NE Saturday into Sunday. Low pressure develops well off the MidAtlantic coast, driving an Arctic cold front through the Carolinas Saturday. Temperatures at 850mb will bottom out at -7C to -12C from south to north. Saturday night's lows will be near 20 away from the beaches with some upper teens over northern zones. Even as the gradient relaxes considerably the few kt of wind that remain the apparent temperature will drop below the Cold Weather Advisory thresholds of 15F for all but perhaps Williamsburg County.

AVIATION /12Z FRIDAY THROUGH TUESDAY/
There is a good likelihood KFLO will experience at least temporary MVFR ceilings and visibility through 14z, with lower probabilities continuing through the remainder of the morning hours. Low level moisture pooled across central and southern South Carolina is to blame for this area of low clouds. There are lower probabilities for this moisture to stream eastward to the coast affecting KMYR and KCRE with MVFR ceilings possible.
KLBT and KILM should remain VFR.

Southwest winds will increase this afternoon as a weak surface ridge axis slides offshore. Inland wind gusts could exceed 20 kt, particularly at KFLO.

An arctic cold front will approach from the north after sunset.
Although moisture is limited with this feature, there may be enough depth of clouds for some showers or sprinkles affecting the KLBT and KILM airports between 23z Fri-03z Sat. As the front pushes through, winds will turn northwesterly at 10-12 knots as dry air pushes across the area. Low level wind shear conditions have potential to develop near the front as models at 1000 and 2000 feet AGL show speeds increasing to 30kt and 40 kt, respectively, after 00z.

Extended Forecast...Ground fog could develop late Monday night.

MARINE
Through Tonight...A period of relatively light winds is expected this morning as a weak ridge of high pressure pushes across the area. Mariners wanting benign boating conditions should take advantage of this lull as much stronger winds are expected to develop tonight behind an arctic cold front. This front should push offshore between 8-11 PM followed immediately by a burst of northwest winds 20-25 knots gusting to 30 knots. A Small Craft Advisory is being issued for this period of adverse weather conditions which will last through Saturday.

Saturday through Tuesday... Arctic frontal passage early in the period to bring advisory-worthy wind gusts through Saturday and most of Saturday night. It is on Sunday when the gradient between the incoming high and the well offshore low eases for decreasing and slightly backing winds. Wind waves will be abating but there will be an emergence of some ENE swell energy. The surface high will sink to our south on Monday further veering the still lightening winds, falling to 10kt or less. The gradient will remain poorly defined on Tuesday bringing a further decrease in wind wave energy though spectral plots continue to show a 12 second easterly swell.

ILM WATCHES/WARNINGS/ADVISORIES
NC...None.
SC...None.
MARINE...Small Craft Advisory from 10 PM this evening to 7 AM EST Sunday for AMZ250-252-254.
Small Craft Advisory from 6 PM this evening to 7 AM EST Sunday for AMZ256.