textproduct: Columbia

SYNOPSIS

A brief cool down is seen today as a weak backdoor front lingers in the area but above normal temperatures and mainly dry conditions are expected to continue Saturday. Another weak front may bring slightly cooler conditions Sunday, but with more dry weather. The passage of a strong cold front early next week brings much colder conditions to close out the year, though the chance of rain during the next seven days is relatively low.

NEAR TERM /THROUGH TONIGHT/

Key message(s):

- Backdoor front begins to retreat back northward through the day.

- More patchy fog possible tonight.

The weak backdoor front is clearly seen on satellite imagery early this afternoon through the deck of stratus along and behind it. The front is stretching from the upstate, through far northern Aiken and northeast Orangeburg Counties then down into Berkeley county along the SC coast. While fog has burned off, stratus will likely linger along and northeast of the front for the coming hours before starting to scatter out. This cloud cover and weak CAD set up should bring a tight temperature gradient from SW to NE across the FA with the CSRA topping out in the low to mid 70s and the Pee Dee only reaching the upper 50s to low 60s. Areas between here likely range from the mid 60s to the upper 60s. This evening and tonight, the front will slowly lift back northward as a warm front in response to a weak surface low moving into the Northeast region. Tonight, low level moisture remains fairly high with dewpoints in the 50s and with gradually clearing skies, some more patchy fog will be possible as lows bottom out in the mid to upper 50s SW of the I-26 corridor, and toward the low to mid 50s NW of here.

SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/

Key message(s):

- Near record temps expected again across the area Saturday afternoon.

- Another backdoor front Sunday brings slightly cooler temps to the area.

Strong upper ridging builds back over the area again on Saturday, which is expected to keep push the frontal boundary away from the area. Behind the front, downslope heating caused by northwest winds are expected to help boost temperatures back up to near record highs once again. The record highs for CAE and AGS for 12/27 are both 77 degrees, which is certainly within the realm of possibilities for reaching. Another piece of shortwave energy is then forecast to rotate around the ridge, helping to push another backdoor front into the area for Sunday. Looking at the various guidance, it looks similar to what we're seeing today. There is lower confidence in the high temperatures for Sunday as it will depend on how far south the front can get. Some of the deterministic guidance, like the ECMWF, is in one camp and keeping it along the NC/SC border, while others, like the GFS, are in another camp and push it to the CSRA. Regardless of where this front ends up, confidence is relatively high that highs Sunday will be cooler than Saturday.

LONG TERM /MONDAY THROUGH FRIDAY/

Key message(s):

- A strong front moves through Monday with gusty winds and a few showers.

- Well below average temps expected Tuesday onward.

The trough that has been giving the West Coast headaches the past few days is expected to finally eject eastward toward our area. An associated strong cold front is forecast to move along with it. While there are still timing differences between the different model solutions, it appears the front moves through the region some time Monday. Temperatures are expected to be warm ahead of the front before crashing after the front passes. Despite this front being strong, the moisture convergence still looks limited, so only isolated to scattered showers are expected on Monday. Much colder air can be expected for the rest of the week with highs generally 10-15F below average for the remainder of the week.

AVIATION /16Z FRIDAY THROUGH TUESDAY/

Restrictions remain early this afternoon before VFR conditions are expected late this afternoon and this evening. More fog/stratus will be possible tonight.

Early this afternoon, the front has stalled out south of the Columbia terminals and right over OGB, bringing MVFR to IFR ceiling restrictions and 5-9 kt winds generally out of the northeast while the Augusta terminals are seeing SCT low clouds and light/variable winds. Continuing through the afternoon, stratus is expected to slowly scatter/rise as the front slowly lifts back northward as a warm front bringing back VFR conditions around 19-21z. Winds will be a bit variable as the current northeast winds at CAE/CUB/OGB should shift a bit more southeasterly and then southwesterly as the front lifts while AGS/DNL should generally keep southwest to west-southwest winds. This evening and tonight, FEW to SCT clouds around 3,500 to 6,000 ft likely remain as winds become light out of the southwest to west. LAMP, HRRR, and NBM guidance are indicating higher confidence in possible MVFR to IFR visibility restrictions early Saturday morning with patchy fog development, but the HRRR and HREF in particular also indicate a bit of stratus. At this time, the more likely restrictions Saturday morning seem to be due to fog but ceiling restrictions cannot be ruled out as well. Conditions are expected to improve through the morning, returning to VFR after 15- 17z with light winds out of the west to northwest.

EXTENDED AVIATION OUTLOOK... Low level moisture could bring morning fog or stratus again on Sunday and on Monday ahead of a strong cold front before drier air filters in on Tuesday.

CAE WATCHES/WARNINGS/ADVISORIES

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