textproduct: Charleston

WHAT HAS CHANGED

The Aviation Section was updated for the 12Z TAF issuance.

KEY MESSAGES

- 1) Cool weather lingers this weekend. Near to slightly above normal temperatures return next week.

- 2) The coastal flood risk will persist into early next week.

DISCUSSION

KEY MESSAGE 1: Cool weather will linger into the weekend. Near to slightly above normal temperatures return next week.

Quiet conditions continue to prevail across the region, as current observations show calm winds and clear skies. Thus, with the aid of efficient radiational cooling, have seen temperatures fall into mid 50s inland to lower 60s along the coast. These values will continue to fall in the coming hours, with locations further inland possibly dipping into the upper 40s prior to daybreak.

Temperatures moderate fairly quickly this afternoon as upper level ridging builds aloft, allowing highs to warm into the upper 70s to lower 80s, which is still a touch below normal for this time of year. Otherwise, expect similar conditions to prevail this evening, as light winds and clear skies yield another chilly night. However, winds out of the south/southwest should help cap lows in the mid 50s.

Looking ahead into next week, will see broad upper level ridging and sfc high pressure linger overhead, keeping conditions quiet across our area. Temperatures will continue to moderate during this time, with highs in the upper 80s to low 90s likely again by mid-week. Moisture then increases Thursday into Friday along the backside of subtropical high pressure centered well offshore over the Atlantic, causing rain chances to return. Nonetheless, confidence remains too low at this time to narrow in on any specifics.

KEY MESSAGE 2: The coastal flood risk will linger into early next week.

Breezy north-northeasterly flow will continue across the region, as a nor'easter churns offshore of the Mid-Atlantic coastline. This combined with the recent full moon will result in minor (possibly moderate) coastal flooding with each high tide cycle this weekend (esp. for the Charleston Harbor).

Charleston Harbor: Coastal flooding concerns will continue today (9/26) with the potential to reach moderate flood stage for Charleston and Colleton County with the morning high tide (~8AM). Thus, plan to issue a Coastal Flood Advisory with this forecast package, which will be in effect from 6 AM until 10 AM. Thereafter, it's likely to see minor coastal flooding conditions through early next week for the Charleston Harbor.

Fort Pulaski: Total water forecasts indicate this morning's and Sunday morning's high tide could peak around 9.5 ft MLLW, which will be close to yielding minor coastal flooding impacts across lower South Carolina and southeast Georgia. Given the borderline nature, will continue to monitor trends in the coming hours and issue a Coastal Flood Advisory if warranted.

AVIATION /12Z SATURDAY THROUGH WEDNESDAY/

VFR will prevail through the 12Z TAF period with SKC skies and NW winds shifting to the SW late this afternoon.

Extended Aviation Outlook: VFR.

MARINE

Today through Wednesday: Seas of 4-6 ft linger across the outer Georgia waters today, where a Small Craft Advisory is currently in effect. Should see seas wane heading into the evening, allowing all headlines to expire. Otherwise, expect fairly quiet marine conditions to dominate the coastal waters through the middle of next week. Some localized sea breeze enhancements should return across Charleston Harbor and the land/sea interface by Tuesday, but wind speeds look to remain fairly tame.

Rip Currents: A lingering 10-12s backswell directed towards the Georgia and Florida coasts will support a moderate rip current risk from Tybee Island south to Sapelo Island both today and Sunday. A low risk is anticipated for the lower South Carolina beaches both days.

CHS WATCHES/WARNINGS/ADVISORIES

GA...None. SC...Coastal Flood Advisory until 10 AM EDT this morning for SCZ149- 150. MARINE...Small Craft Advisory until 8 PM EDT this evening for AMZ384.