textproduct: Charleston

WHAT HAS CHANGED

Removed the key message pertaining to this morning's fog which has dissipated.

KEY MESSAGES

- 1) The coastal flood risk will linger through Friday. Another round of coastal flooding is likely next week.

- 2) Unsettled weather will return Friday through Monday.

- 3) Cooler temperatures along with breezy to windy conditions are likely next week.

DISCUSSION

KEY MESSAGE 1: The coastal flood risk will linger through Friday. Another round of coastal flooding is likely next week.

Tidal departures continue to decrease and the tide forecast for the Charleston Harbor Tide Gage has been decreased to 6.9 ft MLLW, just shy of minor flooding. There is chance that the gage could reach 7.0 ft MLLW for an observation or two, however at this time a Coastal Flood Advisory is not planned. Coastal flooding is not a concern at Fort Pulaski.

Breezy to windy northeast winds induced by strong cold air damming, combined with already high astronomical high tides, will likely result in coastal flooding issues next week. Minor to moderate flooding is likely, with a possibility of reaching major levels. Coastal Flood Watches, Warnings and Advisories could be needed.

KEY MESSAGE 2: Unsettled weather will return Friday through Monday.

The pattern will get more active as we head into late week, and especially over the weekend. Upper ridge will lose influence as a larger scale trough shifts into the eastern U.S. Moisture levels will surge with PWats climbing to around 2.25 inches, which is well above climo for this time of year (near 98th percentile). Showers and thunderstorms are likely each day, with the greatest coverage expected Sunday into Monday with better forcing aloft and the cold front pushing through. Pockets of heavier rainfall will be possible. LREF indicates the chance for rainfall greater than 1" is roughly 65- 75% through Monday evening, with a 25-35% chance for greater than 2". Timing still needs to be refined, but drier air should start to move in Monday afternoon following fropa.

KEY MESSAGE 3: Cooler temperatures along with breezy to windy conditions are likely next week.

Guidance is consistent indicating strong high pressure will wedge south into the Carolinas and Georgia Tuesday into the middle of next week. This will bring notably cooler temperatures and gusty winds to the area. Winds could become supportive of a Lake Wind Advisory for Lake Moultrie, and we will also need to monitor the potential for gusts near 40 mph along the immediate coast/beaches. Otherwise, rain chances will linger, though its unclear how much coverage there will be. Some model solutions hint at a wave of low pressure developing nearby, while others keep any wave and deeper moisture to the south.

AVIATION /13Z THURSDAY THROUGH MONDAY/

12Z TAFs: Fog has developed at KCHS/KJZI/KSAV early this morning. Expect impacts to vsbys and cigs until just after 12Z with sunrise. KCHS will initialize at the 12Z hour with IFR conditions, quickly improving to VFR by 13Z. Thereafter, prevailing VFR at all terminals. Fog is possible again late tonight/early Friday morning.

Extended Aviation Outlook: Flight restrictions are possible in early morning fog/stratus late this week and also in showers and thunderstorms over the weekend into early next week. Gusty winds are likely on Tuesday.

MARINE

Through Sunday: Winds and seas will remain well below Small Craft Advisory thresholds across all marine zones. Winds will surge a bit each afternoon and evening, but speeds should mostly top out in the 10-15 knot range and will be strongest along the land/sea interface.

Monday and Tuesday: High pressure will wedge south into the Carolinas and Georgia following the passage of a cold front. Marine conditions are expected to deteriorate, with Small Craft Advisories likely as early as Monday evening. The worst conditions look to occur on Tuesday when guidance indicates a high probability for winds to reach gale-force (NBM showing 60-80% chances for gusts greater than 34 kt, highest in the waters beyond 20 nm). We will also need to be on the lookout for hazardous beach conditions, including dangerous rip currents and high surf.

CHS WATCHES/WARNINGS/ADVISORIES

GA...None. SC...None. MARINE...None.