Williamsburg, KY Weather

Key Messages

- A light, mainly patchy, frost is possible again early this morning and late tonight, primarily in sheltered valleys away from lakes, rivers, and larger creeks.

- Expect near-normal temperatures throughout the work week, with mostly clear skies and overnight ridge-valley temperature splits likely to continue through at least next weekend.

Update

Issued at 725 AM EDT TUE OCT 20 2026

No significant changes were made to the forecast with mainly just the inclusion of the latest obs and trends for the T/Td grids. These minor adjustments have been sent to the NDFD and web servers along with a freshening of the zones.

Long Term

(Wednesday night through Monday) Issued at 340 AM EDT TUE OCT 20 2026

The forecast remains on track with upper-level ridging keeping eastern Kentucky under fair skies and dry conditions through the weekend. Temperatures will remain near or slightly above average in the upper 60s to low 70s, with overnight lows in the mid to lower 40s, and some 30s in the coldest valley locations. A current upper-level low off the California shores is modeled to progress and phase into the northern stream over south-central Canada over the weekend. How this upper low evolves as it progresses through the Great Lakes remains uncertain, but could have some weather implications for our area by early to middle of next week - beyond the scope of the extended period.

Previous Discussion...

There is reasonably high confidence in dry weather with normal to slightly above normal temperatures through the period.

In terms of our local area, there is good model agreement for the big picture until near the end of the forecast period. The period begins with a weak upper level low and modest troughing off the East Coast, and strong upper level ridging over the central CONUS, especially the plains. With time, the East Coast troughing will further weaken and the ridging will shift eastward as troughing advances into the western CONUS, with the ridge reaching us during the weekend. Until the ridge arrives, we will have a dry northwesterly flow aloft. At the surface, high pressure or ridging based mainly to our north will dominate our area. The flow aloft could support a weak and dying cold front to move south toward the Ohio Valley late in the week, but it will probably not get here, and even if it does it would not have any real effect. Even so, no return to meaningful warm air advection is foreseen either. One model difference to note-- the NAM is much colder with surface temperatures (mainly highs) than the GFS or ECMWF on Wednesday and Thursday. The NAM generates very low and shallow stratus in cold air advection and would suggest high temperatures as much as 15-20 degrees colder than the GFS or ECMWF. Considering the lack of precip or significant systems passing through, this scenario looks highly suspect and is being discounted.

Larger scale model differences finally become more significant early next week in terms of the demise of the upper ridge and how troughing evolves as it advances toward us from the west or northwest. However, in terms of actual effects on our local weather, the differences don't appear to become significant until after this long term period.

Aviation

(For the 12Z TAFS through 12Z Wednesday morning) ISSUED AT 750 AM EDT TUE OCT 20 2026

Surface and upper level ridging will hold in place across the region through the TAF period. This will lead to light easterly to northerly winds with only a few high clouds today. VFR condition will largely prevail. The exception will be valley fog along rivers and larger tributaries through 14Z, that will likely be locally dense with reductions to IFR or lower. The fog is not expected to affect the TAF sites with any visibility reductions.