textproduct: Columbia

SYNOPSIS

A backdoor cold front tonight into tomorrow brings cooler temperatures for most on Sunday along with the chance of a few passing showers. The passage of a strong cold front on Monday brings much colder conditions to close out the year.

NEAR TERM /UNTIL 6 AM SUNDAY MORNING/

Key message(s):

- Record high temps earlier today - Backdoor front moves into the area overnight

After a record setting day with multiple high temp records broken (CAE/AGS) temperatures remain quite mild this evening in the upper 60s to lower 70s despite mostly clear skies and calm winds. A backdoor frontal boundary currently located over central NC, from around Greensboro to Lumberton, will push into the forecast area later tonight before stalling near the CSRA early Sunday morning. Expect stratus clouds to develop during the predawn hours with abundant low level moisture in place and cold advection behind the frontal boundary. The cloud cover and above normal dewpoints will limit radiational cooling but the cold advection behind the front will create a gradient in low temperatures from the upper 40s north to mid 50s in the CSRA.

SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/

Key message(s):

- A backdoor cold front results in cooler temperatures for most along with a few passing showers.

- A stronger cold front sweeps through the region on Monday with breezy conditions during the day and subfreezing temperatures at night.

Sunday and Sunday Night: Sunday will be an interesting day across the region. While the upper ridge axis will pass overhead, a backdoor cold front is expected to move into the FA bringing cooler temperatures for most. While it remains to be seen how far south the boundary will go, the Northern Midlands will see the more significant change compared to today. Latest model guidance shows patchy rain showers passing through the region through the day. Opted to blend in some hi-res guidance in order to better emphasize the patchy nature of the precipitation, while capping PoPs in the Slight Chance category. Clouds associated with the front will also limit warming. Taking all of this into consideration highs were lowered from the NBM, especially across the Northern Midlands where forecast highs are in the upper 50s and lower 60s. The remainder of the CWA have forecast highs in the mid-60s to mid-70s. Skies should remain partly to mostly cloudy at night as a potent cold front approaches from the west. This will limit cooling with lows generally in the mid-50s to around 60 degrees. The chance of rain is low Sunday night but a few showers cannot be ruled out towards daybreak, especially across the western FA.

Monday and Monday Night: A potent trough passes to the north on Monday with the attendant cold front moving through the FA during the morning and early afternoon hours. While PWATs have increased with this model cycle, now up to around 1.25 inches, guidance continues to show limited rainfall potential with the frontal passage. The biggest story will be the potential for gusty winds during the daytime hours followed by strong CAA at night resulting in subfreezing temperatures by daybreak. Winds are expected to quickly increase on Monday with widespread gusts of 25 to 30 mph likely. There should be a delay in the cold air allowing temperatures to climb into the mid-60s to near 70 degrees before falling quickly at night. Temperatures by daybreak Monday should range from the upper 20s to lower 30s, especially if winds drop off early in the night.

LONG TERM /TUESDAY THROUGH SATURDAY/

Key message(s):

- Cool and dry weather prevails during much of the extended.

The year closes with below normal temperatures as troughing sets up over the Eastern CONUS. While guidance trends closer to seasonal values late next week, this will depend on how quickly the trough lifts to the north and upper ridging builds in. The GFS is more progressive by 12-24 hours, which would help explain the warming trend towards the end of the extended. Regardless of temperatures, the chance of rain is low through Friday, with the next chance for precipitation holding off until Friday night into Saturday.

AVIATION /00Z SUNDAY THROUGH THURSDAY/

VFR conditions to start the period, followed by MVFR and likely IFR at CAE, CUB, and OGB.

Mainly clear skies to start the TAF period with light and variable to calm winds at the terminals. A frontal boundary is expected to approach the region overnight, bringing lower cigs to the terminals. MVFR cigs become likely at CAE, CUB, and OGB after about 08z or 09z, but there remains some uncertainty in the timing. Confidence is also increasing for IFR cigs to move over these terminals near daybreak for several hours. Confidence remains low in MVFR cigs making it to AGS and DNL and very low for IFR cigs. Winds become easterly at the terminals, before becoming southerly to southeasterly late in the TAF period.

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

CAE WATCHES/WARNINGS/ADVISORIES

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