FXUS62 KCHS 171104 AFDCHS
Area Forecast Discussion National Weather Service Charleston SC 604 AM EST Tue Feb 17 2026
.WHAT HAS CHANGED...
The aviation section has been updated for the 12Z TAF issuance.
&&
.KEY MESSAGES...
- 1) A period of unsettled and warm conditions for the end of
the week into the weekend.
&&
.DISCUSSION...
KEY MESSAGE 1: A period of unsettled and warm conditions for the end of the week into the weekend.
A ridge of high pressure centered over the Gulf of America builds during the later half of the week, with warm and moist southwesterly surface flow setting up over the region starting on Thursday. Temperatures throughout the atmospheric column consistently flirt with and/or exceed the 90th percentile wrt climatology, as the latest ensemble situational awareness tables continue to show, which will result in daily maximum surface temperatures in the mid 70s to lower 80s Thursday through Saturday. Overnight low temperatures will be similarly warm in the upper 50s to lower 60s, which will be closer to our normal daily highs for this time of year in the mid 60s compared to normal lows in the lower 40s. The forecast does not currently reach/exceed records, though we'll get closest to the records set for February 20 as we'll be warmest that day with inland areas in the lower to mid 80s.
While scattered diurnally driven showers will be possible each afternoon, isentropic lift from positive theta-e advection will add to the unsettled conditions at times. Isolated thunderstorms will also be possible when instability levels rise, and while model agreement is overall good, agreement isn't high enough to pinpoint what day(s) thunderstorms are to be expected.
A cold front is expected to push through the region at some point on Sunday.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
Prior to the 12Z TAFs, light ground fog was observed at both KCHS and KSAV. Any fog this morning should dissipate by 13Z. VFR conditions will prevail at CHS/JZI/SAV terminals through 12Z Wednesday. A weak sea breeze is forecast to shift winds from the SSE this afternoon, speeds between 5 to 10 kts.
Extended Aviation Outlook: VFR through mid-week. The potential for flight restrictions will increase late week into the weekend with possible fog development during the pre-dawn hours.
&&
.MARINE...
High pressure will provide wind and sea conditions well below Small Craft Advisory levels through Wednesday. Very warm and humid conditions are forecast to build across the region Wednesday night and will remain through the rest of the week. Given shelf water temperatures around 50 degrees, wind directions parallel to the coast, and dewpoints around 60 degrees, sea fog is possible beginning Wednesday night. Forecast soundings over the coastal waters indicate a strong BL inversion, extending 300-500 ft from the water. In addition, NAM sfc condensation pressure deficits fall below 5 mbs each night. At this time, a mention of patchy sea fog will be limited to Wednesday and again Thursday night. However, if rain chances decrease Friday and beyond then the potential for sea fog will increase.
A cold front is expected to push across the waters this weekend. Small Craft Advisories could be needed for a portion of the marine zones as wind gusts are forecast to approach 25 kt.
&&
.CLIMATE...
Record High Temperatures:
February 20: KCHS: 82/2018 KCXM: 78/1918 KSAV: 84/1991
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None. SC...None. MARINE...None.
&&
$$
APT/NED