textproduct: Charleston

WHAT HAS CHANGED

Aviation section updated for the 12Z TAFs.

KEY MESSAGES

- 1) Minor coastal flooding is possible expected along portions of the South Carolina coast early this afternoon. - 2) Continued risk for rip currents this weekend.

- 3) Quiet conditions continue with somewhat unsettled weather possible Sunday into Monday.

DISCUSSION

KEY MESSAGE 1: Minor coastal flooding is possible along portions of the South Carolina coast early this afternoon.

Northeast winds will strengthen along the SC coast around sunrise this morning. Gusty northeast winds should increase through the high tide cycle this morning into early this afternoon. As a result, tidal departures should gradually increase through mid-day. The astronomical tide within the Charleston Harbor will peak at 6.31 ft MLLW around 12:58 PM. Given the gusty northeast winds, water levels in Charleston Harbor may crest within minor flood stage early this afternoon. A Coastal Flood Advisory could be needed for Charleston and Coastal Colleton Counties.

KEY MESSAGE 2: Continued risk for rip currents this weekend.

Gusty northeast winds and building seas expected along all beaches of GA and SC today. A High Risk of rip currents will remain until 8 PM this evening.

Reminder: The local rip current program will end later today, October 31 with the afternoon Surf Zone Forecast.

KEY MESSAGE 3: Quiet conditions continue with somewhat unsettled weather possible Sunday into Monday.

Today: Upper level ridging begins to degrade as a wedge of high pressure meanders along the northeast coast, setting up a coastal trough just offshore. As noted in the previous discussion, should see winds pick up through the afternoon, with the strongest gusts expected along the coast. Currently have gusts ranging between 25 to 30 mph, with isolated pockets up to 35 mph possible near Darien. Similar to yesterday, have highs warming into the upper 70s to low 80s. Mid to low-level moisture will also increase during this time, resulting in increased cloud cover through the afternoon. While largely dry conditions are forecast to prevail, can't rule out seeing in isolated shower or two across McIntosh County.

Lake Moultrie: A brief window of breezy winds may occur shortly after sunrise on Lake Moultrie, with gusts nearing 25 knots. Nonetheless, have opted to forgo a Lake Wind Advisory as confidence in strength and duration still remain low.

Sunday: Breezy winds continue across the region, with highs a touch cooler in the mid 70s. Once again, should see dry conditions largely prevail, as the aforementioned coastal low keeps the precipitation shield offshore. In the event that showers do meander a touch inland, expect amounts to remain less than a quarter of an inch.

Sunday Night Onward: The center of the surface high pressure to our north begins to shift out into the Atlantic, with the coastal trough remaining just offshore of our local waters. Combined with increasing low-level moisture and a weak slow moving shortwave, chances for light scattered showers will build across the region late Sunday night through Monday. Again, not expecting to see much in the way of significant rainfall. Rather, will likely only see a few hundredths to tenths at best. While a few showers may linger into Tuesday, overall confidence remains fairly low as model guidance begins to diverge with how the upper level pattern will evolve. So, will continue to monitor trends in the meantime. Otherwise, look for breezy northeast winds to persist, with highs in the mid 70s Monday rising into the upper 70s to lower 80s by Tuesday.

AVIATION /12Z SATURDAY THROUGH WEDNESDAY/

12Z TAFs: VFR. Cirrus will likely stream west to east across the terminals through the TAF period. The pressure gradient will increase across the region today, supporting gusty northeast winds, with gusts around 20 kts common during the daylight hours. Gusts should subside this evening, with steady northeast winds around 10 kts through the rest of the TAF period.

Extended Aviation Outlook: Gusty northeast winds continue, with an increased risk for rain impacts Sunday into Monday.

MARINE

Today through Tonight: A backdoor cold front will push south across the SC/GA marine zones this morning. In the wake of the front, a building ridge of sfc high pressure will yield gusty northeast winds, gusts generally between 25-30 kts. Some gusts into the low 30s are possible across the GA waters and lower SC waters this afternoon. Wave heights will begin the day between 3-6 ft, building to 5 to 8 ft by early this evening. Wave heights may decrease by 1-2 ft overnight. Small Craft Advisories (SCA) will remain in effect for the Charleston Harbor, nearshore SC and GA waters, and outer GA waters today. The SCA for the CHS Harbor will end a 8 PM this evening, remaining outside the harbor due to gusty winds and elevated seas.

Sunday through Wednesday: With high pressure lingering through mid- week, expect northeasterly winds to remain breezy during the day and gusty at night. This will keep wave heights in the 5 to 8 ft range into Wednesday, thus resulting in a prolonged period of SCAs.

CHS WATCHES/WARNINGS/ADVISORIES

GA...High Risk for Rip Currents through this evening for GAZ217-219-239- 241. SC...High Risk for Rip Currents through this evening for SCZ148>151. MARINE...Small Craft Advisory until 8 PM EDT this evening for AMZ340. Small Craft Advisory until 7 AM EDT Wednesday for AMZ360-362- 364. Small Craft Advisory until 7 AM EDT Wednesday for AMZ384.