textproduct: Charleston

WHAT HAS CHANGED

A Dense Fog Advisory has been issued for the entire forecast area through 9 AM.

KEY MESSAGES

- 1) Dense fog is anticipated across much of the southeast South Carolina and southeast Georgia tonight into this morning. A Dense Fog Advisory has been issued for the entire forecast area through 9 AM.

- 2) Unseasonably warm temperatures are expected through early next week, with increasing rain chances beginning this weekend.

DISCUSSION

KEY MESSAGE 1: Dense fog is anticipated across much of the southeast South Carolina and southeast Georgia tonight into this morning. A Dense Fog Advisory has been issued for the entire forecast area through 9 AM.

Observations from METARs and webcams indicate that dense fog has developed across some locations. Given the strong guidance agreement in the development of dense fog a Dense Fog Advisory has been issued for the entire forecast area through 9 AM. Expect conditions to worsen headed towards sunrise. Fog is expected to linger until 9 AM or even 10 AM in some spots.

KEY MESSAGE 2: Unseasonably warm temperatures are expected through early next week, with increasing rain chances beginning this weekend.

Deep-layer high pressure will set up over the Western Atlantic today and persist into early next week. Despite sufficient moisture, persistent subsidence associated with this pattern will suppress widespread convection and support a pronounced warming trend.

Above-normal temperatures are expected to continue through early next week. Afternoon highs will climb into the upper 70s and lower 80s across southeast South Carolina each day. Across southeast Georgia, temperatures will reach the lower to middle 80s. Areas especially near the Altamaha River could see highs peaking in the upper 80s Saturday into early next week. Beach communities will peak several degrees cooler due to the influence of the cooler shelf waters. Overnight lows will remain mild as well; in the upper 50s and lower 60s. Despite these warm temperatures, no records are forecast at this time.

Rain-free conditions are expected today; however, slight chance POPs are currently forecast for the far inland counties both Friday and Saturday where subsidence is expected to be weakest. However, as the ridge begins to flatten Sunday, rain chances will increase into early next week, particularly during the afternoon and evening hours. A series of weak shortwaves passing to the northwest Sunday into Monday could provide additional forcing for showers and thunderstorms as deep moisture remains in place. No severe weather expected at this time.

AVIATION /09Z THURSDAY THROUGH MONDAY/

The 06z TAF period begins with VFR conditions at KCHS/KSAV with LIFR at KJZI as fog is already impacting the terminal. Fog is anticipated to impact all terminals overnight and into the morning hours, with IFR/LIFR cigs/vsbys included in the 06Z TAFs. Conditions should improve to VFR by mid morning and remain VFR through the remainder of the 06Z TAF period.

Extended Aviation Outlook: Restrictive ceilings are possible overnight into the early morning hours each night through the weekend due to low stratus/fog.

MARINE

High pressure will remain the dominant weather feature across local waters, extending across the western Atlantic through this morning. The main forecast challenge through the remainder of tonight and into today will be the sea fog. Satellite imagery and webcam observations indicate that there is sea fog lingering just offshore. While conditions may not be dense yet, a Marine Dense Fog Advisory has been issued for all nearshore waters as conditions are anticipated to get worse headed towards daybreak. While there is no DFA for the Charleston Harbor yet conditions are being monitored and one may be required later tonight.

High pressure will remain centered over the western Atlantic through the weekend, resulting in an easterly/southeasterly flow through Saturday. Winds are then expected to shift out of the southwest Sunday through early next week. Both winds and seas are expected to stay below Small Craft Advisory levels.

Sea fog will continue to be a recurring concern as warm, moist air moves over the cooler shelf waters. Periods of fog may redevelop frequently and could persist through the weekend, potentially lingering into early next week. The fog could become dense at times, reducing visibility for mariners. Additional Marine Dense Fog Advisories could be needed.

CHS WATCHES/WARNINGS/ADVISORIES

GA...Dense Fog Advisory until 9 AM EST this morning for GAZ087-088- 099>101-114>119-137>141. SC...Dense Fog Advisory until 9 AM EST this morning for SCZ040- 042>045-047>052. MARINE...Dense Fog Advisory until 9 AM EST this morning for AMZ350-352- 354.