textproduct: Columbia

WHAT HAS CHANGED

Patchy fog possible tonight. Rain chances continue to diminish for Wednesday as temperatures gradually return to near normal. Aviation discussion updated for 06z TAF.

KEY MESSAGES

- 1. Some patchy fog possible overnight as rain chances become more spotty Wednesday. Warming temperatures and returning diurnal rain chances expected for the late week into the weekend.

DISCUSSION

Key Message 1: Some patchy fog possible overnight as rain chances become more spotty Wednesday. Warming temperatures and returning diurnal rain chances expected for the late week into the weekend.

Patchy fog is possible tonight with a moist airmass in place and clearing skies in the wake of a stubborn frontal boundary. RH values are already in the mid to upper 90s in some spots, and skies are starting to clear from the north. Surface winds are expected to completely decouple as well, helping create a favorable setup, especially near bodies of water.

As we move into Wednesday, rain chances diminish across most of the forecast area with the exception of southern locales. The patterns is a bit odd for the next few days as low pressure retrogrades west away from the region and flow through the column becomes predominately easterly. This will reinforce our high PWAT values at 1.7-2" over the next few days, but the lack of forcing will limit widespread convection. As heights and thicknesses increase over the next day or two, temperatures will rise back to near normal levels. By the weekend, ensembles and global models depict an elongated upper ridge stretching from the central CONUS, toward the Ohio Valley. Low level flow returns to the south to southwest and should induce a couple more degrees of warming. There is also a higher potential for some diurnally driven convection as a few disturbances move through the flow and provide a bit more of a trigger and support for storms.

AVIATION /04Z WEDNESDAY THROUGH SUNDAY/

Showers Move Out, Patchy Fog Possible Towards Daybreak....

Radar tonight shows scattered showers moving across parts of the forecast area, mainly near AGS/DNL/AIK. Showers have tapered off around CAE/CUB but will maintain VCSH there for another hour or two in case something new pops up. The main story for tonight is the potential for low clouds and/or fog. Guidance is leaning to the latter possibility and RH values are near 100 percent at OGB/AGS/DNL/AIK suggesting fog may develop during the next few hours at these terminals in particular. Once any low clouds and fog lift, a fairly nice day is expected on Wednesday as drier air pushes in and confines the showers mostly to Georgia. AGS/DNL will probably have a light shower or two around but widespread coverage is unlikely.

EXTENDED AVIATION OUTLOOK...The threat for restrictions eases for the end of the week into the upcoming weekend as conditions begin to dry out.

CAE WATCHES/WARNINGS/ADVISORIES

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