textproduct: Charleston

WHAT HAS CHANGED

All sections have been updated.

KEY MESSAGES

- 1) The coastal flood risk will linger this week.

- 2) Warm and dry conditions will extend through most of the week.

- 3) Unsettled weather could return late week, and possibly persisting through the weekend.

DISCUSSION

KEY MESSAGE 1: The coastal flood risk will linger this week.

The risk for minor to near moderate coastal flooding will continue through most of this week, mainly impacting the coastal portions of Charleston and Colleton Counties. Coastal flooding will be near moderate levels both Tuesday and Wednesday mornings with minor flooding Thursday and possibly Friday mornings.

Today: While guidance guidance supports minor flooding with this morning's high tide around 10 AM tides have been consistently over performing. There are a few possibilities for the over- performance of the recent tides such as a slowing of the gulf stream or the build up of tidal waters across inland waterways due to the extended period of coastal flooding. The tide forecast has been updated to a value of 7.4 ft MLLW, which would be a 0.8 ft departure. Given the most recent high tide was still a departure of 0.9 ft, this value is achievable. A Coastal Flood Advisory has been issued for Charleston and Coastal Colleton Counties.

KEY MESSAGE 2: Warm and dry conditions will extend through most of the week.

Ridging aloft will build into the southeastern states, yielding a rain-free pattern through most of the week. High temperatures will climb into the mid to upper 80s daily, roughly 5 degrees above normal for late Sept/early Oct, with parts of Southeast Georgia reaching the lower 90s. Lows will gradually warm each night, hovering in the mid to upper 60s inland and low to mid 70s near the beaches.

KEY MESSAGE 3: Unsettled weather could return late week, and possibly persisting through the weekend.

Upper ridge will start to weaken late week into the weekend as a broad trough shifts to the Northeast. At the surface, a cold front will approach the region and possibly stall nearby, before a stronger shortwave eventually pushes the front through early next week. Deep moisture will overspread the area with ensembles indicating PWats exceeding 2 inches (90-95th percentile of climo). This pattern will support increasing rain chances with showers and thunderstorms possible each day. Some uncertainties remain with the evolution of this system, but it currently looks like the latter half of the weekend could be the most active.

AVIATION /06Z TUESDAY THROUGH SATURDAY/

VFR conditions are expected to prevail through 12Z Wednesday at CHS/JZI/SAV terminals. MIFG has been introduced at KCHS/KJZI to account for some ground fog forming early this morning. However, little to no impacts are currently forecast due to fog.

Extended Aviation Outlook: VFR.

MARINE

Quiet marine conditions will prevail across the local waters through the rest of the week and into the weekend. 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. Next time period of concern looks to be Monday into the middle of next week following a cold front.

CHS WATCHES/WARNINGS/ADVISORIES

GA...None. SC...Coastal Flood Advisory from 8 AM this morning to noon EDT today for SCZ149-150. MARINE...None.