textproduct: Jackson

KEY MESSAGES

- Showers and thunderstorm chances will persist through the end of the week. The greatest coverage is expected from today through Thursday night. Some of the storms could arrive as organized clusters with a distinct potential for strong to damaging wind gusts - mainly today and tonight. - Instances of excessive rainfall may occur where storms are most persistent, leading to elevated concerns for flooding - particularly today into tonight.

- A Flood Watch is now in effect for the entire forecast area through 2 am Thursday morning, primarily for flash flooding.

UPDATE

Issued at 1045 AM EDT WED AUG 12 2026

14Z sfc analysis shows the mesoscale factors in play over eastern Kentucky this morning with a meso-high noted over northeast parts of the state and a boundary pushed to the southwest. This will remain a focus for storms dropping in from the northwest where they continue to blow up. There will be lulls of just light rain or dry weather, though the trend favors additional rounds of storms through the day - probably favoring the southwest parts of the JKL CWA - closer to the instability gradient. Currently, temperatures are running in the mid 60s with the on-going rain to the lower 70 in the far southwest. Meanwhile, amid light and variable winds, dewpoints are generally in the mid to upper 60s. Have updated the forecast mainly to tweak the PoPs per the radar trends but also added in the latest obs and tendencies for the T/Td/Sky grids. These adjustments have been sent to the NDFD and web servers along with a freshening of the FFA, SAFs, and zones.

UPDATE Issued at 910 AM EDT WED AUG 12 2026

No significant changes were made to the forecast with mainly just the PoP adjustments for the near term weather targeting the southwest parts of the area as well as the inclusion of the latest obs and trends for the T/Td/Sky grids. These minor adjustments have been sent to the NDFD and web servers along with a freshening of the SAFs and zones.

LONG TERM

(Friday through Wednesday) Issued at 357 PM EDT WED AUG 12 2026

At the onset of the long term period, eastern Kentucky will find itself in continued northwest flow aloft, sandwiched between ridging over the southeastern CONUS and troughing over the Northeast. At the surface, an area of low pressure will sit over Atlantic Canada, with a long and poorly defined cold front extending back through the Mid Atlantic, just north of the forecast area. This front will sag south through the area on Friday, bringing a chance for additional convection. As in previous days, the environment will support intense rainfall rates with any convection that does pass through; LREF mean PW values range from 1.8-2 inches on Friday afternoon, well within the 90th percentile or higher when compared to climatology, and given already moist soils, flash flood risk could be higher than in typical summer thunderstorms. WPC has maintained a Day 3 Marginal (1/4) flash flood risk for our area to account for this. Additionally, at least moderate instability is likely to build ahead of the front, which could potentially support strong convection. Given some model guidance suggests the potential for additional shortwave impulses within broader northwest flow aloft, additional MCS type activity cannot be ruled out on Friday (although uncertainty remains high). That being said, upper level flow will be weak, with deep layer shear generally favored to remain under 30 kts across the forecast area, which would not conventionally support widespread severe weather. Even so, some machine learning guidance has been comparatively more aggressive in highlighting eastern Kentucky as a potential location for additional damaging winds. Given some of the signals in global models, it is still plausible that MCS activity could increase the potential for severe wind gusts Friday afternoon/evening, although confidence in this scenario remains very low. For now, NBM PoPs were maintained given a lack of baseline model agreement, but with the caveat that rain chances/timing will require some refining as uncertainty decreases.

By the weekend, the front will have passed through the forecast area. Meanwhile, the upper level ridge will continue to build into our area. This will usher in a period of hotter and drier weather, with high pressure working to suppress most convection through the weekend. Unfortunately, the aforementioned cold front will do little to bring down heat or humidity. Behind the front, temperatures will actually trend warmer in accordance with increased upper level ridging (highs likely in the 90s), and dewpoints will remain in the 70s. Accordingly, apparent temperatures will be warm, likely in the upper 90s or perhaps even the low triple digits on Saturday and Sunday afternoons. Overnight temperatures will only provide limited relief given a continued moist environment; although radiative conditions will be ideal, valleys may only end up being a few degrees cooler than ridges at most, with typical valley fog formation possible overnight.

Early next week will mark a return to more quasi zonal flow aloft as an upper level trough begins to dig toward Kentucky and ridging retreats to the southwest, initiating a return to a somewhat more active period. Notably, an approaching cold front on Monday will bring renewed shower and storm chances. In comparison to the previous cold front, the air mass behind this front will be marginally drier, with dewpoints expected to fall into the mid to upper 60s in most locations. High temperatures will also be around 5 degrees cooler for most locations, marking a return to a more typical August weather regime.

AVIATION

(For the 18Z TAFS through 18Z Thursday afternoon) ISSUED AT 339 PM EDT WED AUG 12 2026

There were a few light showers near/north of I-64 at the start of the period, but VFR conditions prevailed across the area. Widespread thunderstorms were present over south central IN and are expected to develop southeast into KY late this afternoon and evening. As has been the case in recent days, pinning down the actual evolution of the convective system is rather elusive. A TEMPO group has been used in the TAFs for the possibility of thunderstorms and IFR or worse conditions this evening. Once this moves out, mainly VFR conditions are in the forecast until late tonight. There may be fog/low clouds that develop overnight, but the extent of this will depend on how precip play out prior and the extent of clearing. At this point, have limited it to valleys and not at TAF sites, but this will need to be monitored for possibly updates. Any fog should dissipate on Thursday morning, but a period of MVFR ceilings is expected for some places as heating/mixing gets underway in the morning.

JKL WATCHES/WARNINGS/ADVISORIES

Flood Watch until 2 AM EDT Thursday for KYZ044-050>052-058>060- 068-069-079-080-083>088-104-106>120.