textproduct: Columbia

SYNOPSIS

A much colder air mass builds into the region today with below normal temperatures and continued breezy conditions. Near to below normal temperatures will then prevail through much of next week. The chance of rain during the next seven days is low, less than 20 percent.

NEAR TERM /THROUGH TONIGHT/

Key message(s):

- Lake Wind Advisory continues today with strong wind gusts.

- Much colder today with strong cold advection

-Increased fire danger with low RH and gusty winds

Cold front pushing into the Upstate at this time and should cross the forecast area during the predawn hours which will usher in a much cooler and drier air mass through the day. Upper trough axis will traverse the region today with strong 850mb winds expected to mix down to the surface resulting in westerly winds around 15 to 20 mph with gusts 30-35 mph and cannot rule out a few gusts to 40 mph. HREF probabilities of gusts over 35 mph continue to be high (> 60%) and the Lake Wind Advisory continues through 7pm although there is currently a lull in strong winds until the front moves through.

A much colder and drier air mass will build into the region behind the front today with high temperatures likely to occur early with strong cold advection expected through the day. High temperatures expected to be 20-25 degrees colder than yesterday ranging from the mid 50s west to lower 60s east. Cold advection continues tonight as high pressure builds into the forecast area and lows expected to dip down into the mid to upper 20s with strong radiational cooling as winds diminish late tonight with a very dry air mass in place.

SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/

Key message(s):

- Mostly sunny and chilly on Monday with lighter winds.

- Temperatures warm to around seasonal values Tuesday and Wednesday.

High pressure will be in control of the weather on Monday resulting in mostly sunny skies, lighter winds, and much cooler temperatures. CAA will remain strong as daytime temperatures likely struggle to get into the lower 50s. Conditions will be ideal for radiational cooling Monday night as temperatures once again fall into the 20s. Southwest winds on Tuesday and Wednesday will promote warming temperatures as highs return to seasonal values for Mid-January with highs both days in the upper 50s to near 60 degrees. Clouds increase Tuesday night into Wednesday and there is a low, less than 20 percent, chance for a passing shower or two in the coastal plain but otherwise it is a dry forecast for the period.

LONG TERM /THURSDAY THROUGH SATURDAY/

Key message(s):

- Low end risk for a few showers on Thursday as a potent upper trough passes through the region.

- Below normal temperatures return for the late week period.

A potent upper trough will pass through the FA on Thursday resulting in a return to below normal temperatures, perhaps colder than Monday, along with a chance for rain. While there is sufficient upper support shown in the guidance, moisture is lacking suggesting that rain chances will once again be on the low end at 20 percent or less. Friday is chilly once again before some air mass modification is possible ahead of the next storm system slated to arrive near the end of the extended. Overall, cold and dry weather is favored in the long term.

AVIATION /12Z SUNDAY THROUGH THURSDAY/

High confidence in VFR conditions through the period.

A cold front has pushed east of the Midlands with skies expected to gradually clear through the morning hours. Winds have shifted westerly and increased to 10 to 15 knots with gusts to 20 knots but should increase to around 15 to 20 knots with gusts as high as 30 knots through the afternoon with deep mixing expected. Wind gusts subside with sunset.

EXTENDED AVIATION OUTLOOK...No significant aviation concerns through the first half of the week.

FIRE WEATHER

Fire weather concerns are elevated today as well due to the expected rapid drying with RH values dropping to near critical values and strong wind gusts over 30 mph with deep mixing. The SC Forestry Commission has issued a Red Flag Fire Alert for increased fire danger discouraging burning from the Midlands to the coast. Considered an increased fire danger statement given drying fuels and expected gusty winds but ERC values remain quite high across the region and after coordination with surrounding offices, decided against a statement at this time.

CAE WATCHES/WARNINGS/ADVISORIES

SC...Lake Wind Advisory until 7 PM EST this evening for SCZ016-018- 020>022-025>031-035-037-038-041-115-116-135>137. GA...Lake Wind Advisory until 7 PM EST this evening for GAZ040- 063>065-077.