textproduct: Charleston

SYNOPSIS

High pressure will prevail through the remainder of the holiday week. A cold front will move through the area early next week.

NEAR TERM /THROUGH TONIGHT/

Through Sunrise: MOS and some ensembles show increasing probabilities of fog early this morning. Though, satellite imagery and surface observations indicate pockets of stratus forming around 5,500 ft and only a few areas of some ground fog. Furthermore, high level clouds occasionally moving over our area appear to be interrupting fog formation. We added patchy fog to the forecast as a starting point, and may need to adjust more based on surface observations. Regardless, any ground fog that forms should quickly dissipate around sunrise.

Today and Tonight: The mid-levels will consist of northwest flow over our area, with heights gradually lowering. At the surface, High pressure will remain centered over the northeastern portion of the Gulf. A weak stationary front located roughly along our northern tier of counties early this morning will transition into a warm front and lift north into this afternoon, then dissipate. Then, a cold front will approach from the north late tonight. However, the cold front is not expected to reach our area overnight. Despite all of these synoptic features, dry weather is forecasted. Morning clouds should dissipate, setting the stage for a nice day, followed by some increasing clouds this evening and overnight. Temperatures will remain well above normal. Highs will peak in the mid to upper 70s across most of our area, except cooler at the beaches. Lows will generally be in the 50s.

SHORT TERM /FRIDAY THROUGH SUNDAY/

High pressure will remain to the south Friday into Saturday. Meanwhile, a backdoor front will drop towards the area early Friday, likely stalling nearby before lifting back north. Main impact with the front will be some increased cloud cover and slightly cooler (although still above normal) temperatures over northern zones depending where the front ends up. Warm and dry conditions will persist on Saturday. The highlight of the day will be the temperatures, which are forecast to peak in the mid to upper 70s over most locations. These values are within a few degrees of records (see climate section below).

On Sunday, mid level ridge axis will shift overhead in advance of the next trough passing through the Plains. It should be another warm and dry day with highs spanning the 70s.

LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/

A mid level trough will shift into the eastern U.S. on Monday, sending a stronger cold front to the area. Frontal passage has trended slower, so we should see temps back up in the 70s before the front arrives in the afternoon or evening. Isolated showers could accompany the front, but rain amounts look minimal, a few hundredths of an inch at best (LREF 90th percentile for 24 hr precip is only 0.06").

Noticeably colder temperatures are expected behind the front for Tuesday and Wednesday. There is a concern for sub-freezing temperatures to return, with Tuesday night into Wednesday morning looking the chilliest. LREF probs for wind chills of 20 degrees or lower is generally around 10-20% west of I-95. No precip is expected during this time period.

AVIATION /06Z THURSDAY THROUGH MONDAY/

06Z TAFs: The TAFs start out with VFR. Though, MOS and some ensembles show increasing probabilities of flight restrictions due to fog early this morning. Though, satellite imagery and surface observations indicate pockets of stratus forming around 5,500 ft and only a few areas of some ground fog. Furthermore, high level clouds occasionally moving over our area appear to be interrupting fog formation. So we'll keep the TAFs VFR early this morning, but may need to amend to add flight restrictions if observations point to ground fog forming. Regardless, the daytime through the end of the TAF time period is expected to be VFR.

Extended Aviation Outlook: A brief period of MVFR cigs/vsbys will be possible Friday morning. Gusty winds are possible on Monday.

MARINE

Through Sunrise: There are low probabilities of some sea fog forming. Any that does manage to form will be short-lived and dissipate around sunrise.

Today and Tonight: High pressure will remain centered over the northeastern portion of the Gulf. A weak stationary front located roughly along our northern tier of counties early this morning will transition into a warm front and lift north into this afternoon, then dissipate. Then, a cold front will approach from the north late tonight. Despite all of these synoptic features, winds and seas won't be high enough to prompt any Small Craft Advisories.

Friday through Tuesday: Marine conditions are expected to remain below Small Craft Advisory criteria through the weekend, with winds generally 15 knots or less and seas 2-4 feet. The main time period of concern is Monday into Tuesday ahead of and behind a cold front. Winds gusts around 25 kts and seas up to six feet will be possible, especially across the outer GA and nearshore Charleston County waters.

CLIMATE

Record High Temperatures:

December 25: KCXM: 76/2008

December 27: KCHS: 78/2021 KCXM: 76/2015 KSAV: 80/2015

CHS WATCHES/WARNINGS/ADVISORIES

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