textproduct: Charleston

SYNOPSIS

Strong Atlantic high pressure will prevail into this weekend, then a cold front will move through Monday. High pressure will then rebuild.

NEAR TERM /UNTIL 6 AM THIS MORNING/

Overnight: Here it is early April during the overnight hours, and many temperatures and dew points are still above 70F. This is the result of a southerly synoptic flow and partly to mostly cloudy skies. Since winds never fully decouple, we'll be lucky to get lows down into the upper 60s, or about 15F above climo. Low stratus will be widespread with considerable moisture trapped beneath a 2-3C inversion. Given that 925 mb winds are 20-30 kt, these clouds will not build down low enough to create more than some patchy fog concerns. The most likely occurrences of such will be where rainfall occurred Wednesday.

SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY/

Deep layered ridging over the Eastern United States and western Atlantic will maintain dry weather and above normal temperatures. A prevailing southerly flow will help enhance the afternoon sea breeze each day, so locations closer to the coast will remain considerably cooler than places farther inland. Highs inland will reach the mid to upper 80s each day, with a few readings in the lower 90s possible closer to the Central Savannah River Area (CSRA).

LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/

Ridging will continue through Sunday, then a longwave trough will sweep east Monday, pushing a strong cold front through the area. Fairly widespread showers and thunderstorms expected Monday, then temps cool down considerably for Tuesday and Wednesday.

AVIATION /06Z THURSDAY THROUGH MONDAY/

KCHS/KJZI/KSAV: Low stratus will continue to develop and expand in coverage, leading to the development of flight restrictions at all terminals into this morning. We show MVFR at KCHS and KJZI, but IFR at KSAV where we begin at that category with the latest TAF set, while the HREF shows higher probabilities of such than at the other airfields. A return to VFR isn't expected until 16-17Z when mixing heights finally climb enough. S winds into this morning never drop below about 8-10 kt, and then during the heating of the day gusts of around 20 kt or so occurs during the late morning and afternoon, before gusts diminish by sunset. Flight restrictions will return tonight, but that will be addressed in future TAFs.

Extended Aviation Outlook: Nighttime ceiling restrictions possible Thursday night.

MARINE

Overnight: High pressure across Bermuda will continue to dominate with increasing south to southeasterly flow across the coastal waters. Winds of 10 to 15 knots will be common with some higher gusts, while seas build into the 3 to 5 foot range.

Fairly quiet marine conditions expected Thursday through Saturday. Southerly flow will strengthen Saturday into Sunday as an upper trough approaches from the west. 6 ft seas could encroach on the outer portions of the offshore GA and nearshore SC waters. Sunday and Sunday night we could see 25 kt wind gusts in the Charleston nearshore waters and Charleston Harbor, so Small Craft Advisories cannot be ruled out.

CLIMATE

Record High Temperatures:

April 5: KSAV: 90/1988

April 6: KSAV: 90/1967

Record High Minimum Temperatures:

April 3: KCHS: 67/2012 KCXM: 68/2012 KSAV: 68/2012

April 4: KCHS: 70/1974 KCXM: 69/1974 KSAV: 69/1974

April 5: KCHS: 65/2017 KCXM: 67/2023 KSAV: 66/1957

April 6: KCHS: 68/2023 KSAV: 68/2023

CHS WATCHES/WARNINGS/ADVISORIES

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