textproduct: Columbia

WHAT HAS CHANGED

Updated Aviation Discussion for 12Z TAFs.

KEY MESSAGES

- 1. Above normal temps expected through Monday, with a backdoor front ushering in drier and slightly cooler air through the middle of next week.

DISCUSSION

KEY MESSAGE 1: Above normal temps expected through Monday, with a backdoor front ushering in drier and slightly cooler air through the middle of next week.

Convection from earlier this week has diminished for the most part, shifting eastward gradually this evening. Forcing for ascent is slowly doing the same as the 500 hPa trough across the TN Valley lifts northeastward through the Appalachians. A sharp gradient in PWs is noted to our west, and slightly drier air is expected to push into the area on Sunday. The feature that is forecast to dominate the weather over the next week is expected to begin building tonight and into Monday. Persistent troughing across the western CONUS is expected to yield strong height rises across the southeastern CONUS, resulting in one of the stronger 500 hPa ridges on record for this time of year (heights are forecast to exceed NAEFS climatology for several days). On the northern side of this, a stout shortwave is expected to round into the northeastern CONUS, with strong convergence between the backside of this and the trailing ridge. This convergence is forecast to usher in a seasonally strong surface high pressure system into the Northeast, ridging down through the Mid-Atlantic and Carolinas by the middle of the week. This surface high is forecast to makes its way towards us via backdoor front on Monday night and early Tuesday, with near normal highs & below normal dewpoints and PWs behind it. Monday will be quite warm ahead of this front, with highs forecast in the mid 90s. But Tues/Wed/Thur should feature highs in the upper 80s/lower 90s, dewpoints in the low 60s during the afternoons (maybe even upper 50s!), and overnight lows in the mid 60s. Overall, compared to our weather in recent weeks, it looks fairly nice for several days this week. By the end of next week and next weekend, moisture should return and increase precip chances along with it.

AVIATION /10Z SUNDAY THROUGH THURSDAY/

Early morning IFR/LIFR stratus through 14/15Z.

Convective debris cloudiness has cleared out and stratus and some patchy fog has developed in the presence of ample low level moisture due in part to yesterday's rainfall. Decent mixing with SW winds around 5 kts at the surface has hindered widespread fog development except at the more sheltered sites. IFR/LIFR ceilings are likely to continue until 14Z at all TAF sites.

Morning restrictions should continue through 14-16z today before VFR returns with 5-8 kt winds out of the west. A few showers are possible in the afternoon, but confidence is too low to include in the TAFs at this time. The most likely site to receive rainfall would be OGB since moisture will be deeper to the east. Patchy fog will be possible early Monday morning but moisture is very shallow. AGS and OGB could have some brief vis restrictions around sunrise but widespread restrictions seem unlikely.

EXTENDED AVIATION OUTLOOK...Rain unlikely for much of the week but there will still be some potential for early morning fog/stratus persists at least for early this week.

CAE WATCHES/WARNINGS/ADVISORIES

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