textproduct: Columbia

WHAT HAS CHANGED

No major changes to the forecast. Updated for the 12z TAFs.

KEY MESSAGES

- 1. Elevated fire weather concerns and periodic smoke impacts will persist through Friday.

- 2. Rain chances increase this weekend into early next week, but meaningful drought relief remains uncertain.

DISCUSSION

Key Message 1: Elevated fire weather concerns and periodic smoke impacts will persist through Friday.

A dry air mass persists over the region with relative humidity potentially dropping below 20 percent briefly today and below 30 percent Friday. Much of the area remains in severe to extreme drought. Despite the lack of stronger winds, the combination of low RH and dry fuels will maintain elevated fire danger each afternoon. HRRR smoke guidance once again favors lingering smoke over the area today as weak southwesterly flow will continue to transport smoke from wildfires in southern Georgia and northern Florida over the area. South Carolina Department of Environmental Services issued an Air Quality Alert for today for the CSRA and Midlands of South Carolina. In addition, the SC Forestry Commission continues a Burn Ban until further notice.

Key Message 2: Rain chances increase this weekend into early next week, but meaningful drought relief remains uncertain.

A more unsettled pattern is expected to develop as the upper ridge breaks down and the Bermuda high weakens. HREF members are indicating some isolated shower activity Friday, although looking at forecast soundings, even with a bit of an increase in PWATs, significant low level dry air will limit the potential of any rain from reaching the surface. Higher chances for showers and potential thunderstorms Saturday associated with a cold front, although model consensus is that this system will be relatively progressive, limiting total rainfall. Isolated chances for additional showers Sunday and Monday with another front likely approaching Tuesday leading to higher coverage of showers and isolated storms. While there will be several chances for rain, the drought is likely not going to be significantly reduced anytime soon as 20-30% of GEFS members and less than 10% of EC ensemble members showing higher than an inch of rain through the period and we will need much more than that to eliminate the drought across the area.

AVIATION /12Z THURSDAY THROUGH MONDAY/

VFR conditions are expected to continue, with the exception of brief, periodic dips into MVFR for smoke.

Little change to the forecast is expected as smoke is forecast to hang around today. We are on the western periphery of a surface high pressure, with wind trajectories out of the south and southwest generally. Smoke is expected to be the biggest issue through the day today as guidance continues to suggest that more will move into the area today. Expect a general vis of 6sm and haze, with some dips into MVFR through the day. This occurred yesterday & it is expected it will be a problem again today. Southwesterly winds are expected through the period, oscillating between 5 and 10 knots. Expect winds to relax a bit tonight but still remain up around 3-5 knots.

EXTENDED AVIATION OUTLOOK...Periods of vsby restrictions due to smoke are likely to persist through at least Friday. Otherwise, dry conditions should limit fog development. Rain chances increase this weekend, which may introduce restrictions at times, though confidence in timing and coverage remain low.

CAE WATCHES/WARNINGS/ADVISORIES

SC...Air Quality Alert until 8 PM EDT this evening for SCZ018- 020>022-025>031-035-037-038-041-135>137. GA...Air Quality Alert until 8 PM EDT this evening for GAZ064-065.