textproduct: Columbia

WHAT HAS CHANGED

Updates to aviation section. Rain chances have slightly increased for the mid to late week period.

KEY MESSAGES

- 1) Below average temperatures continue to end the weekend with a warm up expected next week.

- 2) Rain chances increase during the second half of the week.

DISCUSSION

KEY MESSAGE #1: Below average temperatures continue to end the weekend with a warm up expected next week.

Surface high pressure should work into the region through the day today and tonight, aiding in bringing strong radiational cooling conditions as a cold and very dry airmass remains in place behind a cold front. This should allow temperatures to fall into the low to mid 20s across the FA with some spots in the upper teens possible. Temperatures remain around 10 degrees below normal on Sunday with another chilly night in the 20s likely. Confidence in temperatures and wind chills remaining above Cold Weather Advisory criteria each night is fairly high. After this, deterministic and ensemble guidance show strong ridging moving into the Southeast for the early week, bringing a warm up where temperatures could begin to reach the 70s on Tuesday and possibly again on Wednesday. Uncertainty remains in temperatures for the late week period as IQR ranges remain fairly large, though there has been a bit of a trend for temperatures to at least remain near average through the end of the forecast period.

KEY MESSAGE #2: Rain chances increase during the second half of the week.

There is high uncertainty in the synoptic pattern after Tuesday- Wednesday this upcoming week as can be seen in the most recent LREF cluster analysis. The main uncertainty between clusters stems from the degree of ridging that can build back into the central US and also the strength of troughing over the Northeast. One consistency amongst clusters and deterministic guidance is that moisture should steadily increase across the region heading into Wednesday and through the end of the forecast period where any shortwave impulse could bring rain chances back to the area. The recent 12z GFS has become better aligned with it's AI counterpart, showing a shortwave and associated rain chances move into the region Wednesday and into Thursday before guidance diverges more. Overall, increasing moisture during the mid to late week period could aid in bringing back rain chances to the FA, but uncertainty in the location of forcing remains.

AVIATION /18Z SATURDAY THROUGH THURSDAY/

VFR conditions will prevail at the terminals.

Northwesterly winds will persist at the terminals through the day, with deeper mixing across the Midlands terminals resulting in some gusts of 15-20 kt at times at CAE,CUB and OGB. Wind gusts will diminish with the loss of diurnal heating this evening, with generally variable to NE winds 5 kt or less through Sunday morning. Clear skies initially, but some high level cirrus could spread over the area during the night, perhaps a few mid level clouds over the Midlands terminals as well by Sunday morning.

EXTENDED AVIATION OUTLOOK...No anticipated aviation concerns through early next week. Restrictions possible moving into mid- week as another system pushes into the region and brings rain potential along with it

CAE WATCHES/WARNINGS/ADVISORIES

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