textproduct: Jackson

KEY MESSAGES

- Showers and thunderstorms return Friday. A few strong to severe storms are possible, bringing a threat for an isolated tornado or damaging wind gusts.

- An unsettled and wet pattern continues through the Memorial Day weekend and into next week with repeated rounds of rain and thunderstorms.

- Heavy downpours are likely with this activity. Total rainfall amounts of 1 to 2 inches are expected through Saturday morning with locally higher amounts and isolated flooding concerns.

- Despite the rain, it will be warm and humid through the holiday weekend with highs in the mid 70s to mid 80s.

UPDATE

Issued at 1150 PM EDT THU MAY 21 2026

Minor updates were made mainly to adjust pops down compared to guidance pops over all but the Lake Cumberland vicinity for the first few hours of the period as well as to trend temperatures and dewpoints toward recent observed trends. As the stalled or nearly stalled boundary to the south of the region begins to lift north as a warm front overnight/toward dawn coverage of showers should increase. Low clouds will also linger north of the warm front and at least ridgetop locations should have stratus build down fog as well.

UPDATE Issued at 720 PM EDT THU MAY 21 2026

Current radar imagery shows an area of showers ambling northeast into our southern counties from Tennessee, where the frontal boundary is currently located. This activity should decline over the next few hours with the loss of daytime heating, but PoPs were bumped up in this area over the next few hours to account for this radar trend. Overnight, ample moisture and a temporary lull in shower activity should allow for fog to set in for may locations, so fog coverage was increased for tonight's forecast. Beyond that, temperature and dewpoint grids were freshened up to reflect recent trends.

LONG TERM

(Saturday through Thursday) Issued at 327 PM EDT THU MAY 21 2026

The forecast period begins with a surface low moving northeast through the Mid-Mississippi Valley into the Ohio Valley. The associated warm front is progged to lift slowly northward with the surface low. This will usher in a WAA regime with climbing temperatures; however, along with the rising temperatures, widespread showers and thunderstorms will be likely. Highs Saturday are forecast to be in the upper 70s to lower 80s, accompanied by a nearly 100 percent chance of rain throughout the day. Forecast soundings Saturday afternoon paint a picture of efficient rainfall efficiency, while also hinting at a conditional strong to severe storm threat. Precipitable water values are upwards of 1.60 to 1.70 inches. On the severe side, around 1500 to 2000 J/kg of SBCAPE will exist alongside moderately steep lapse rates; however, vertical wind shear is quite meager, which remains the primary limiting factor. Even so, it would not be surprising if the SPC issues a Marginal Risk. PoP values start to diminish for the overnight period as diurnal instability wanes and the primary frontal forcing moves off to the north. However, another surface low moving northeast will quickly fill the void, allowing for increasing rain chances beginning early Sunday morning.

Sunday brings another warm frontal passage with showers and thunderstorms possible throughout the day. Temperatures start to warm into the low to mid 80s behind the warm front, but the big story will continue to be the ongoing shower and thunderstorm threat. PWs climb higher Sunday into Monday as efficient moisture advection shifts into the area behind the warm front. PW values will climb to around 1.80 inches, exhibiting a skinny CAPE profile on soundings with very little overall instability present hinting at efficient rainfall taking place. This active pattern will continue through the forecast period. Temperatures will remain largely seasonal, but repeated rounds of showers and storms are expected. Through the entire extended forecast period, the forecast total QPF will range from over an inch in the Bluegrass/I-64 corridor, up to 2.00 inches in the Lake Cumberland area, and almost 2.50 inches across the east-central part of the CWA. These numbers will certainly fluctuate depending on convective activity and where mesoscale bands set up, but nonetheless, this will be a wet Memorial Day weekend into next week.

In summary, an active and unsettled weather pattern will dominate the region through the holiday weekend and into next week as a series of surface lows and warm fronts track across the Ohio Valley. While robust warm air advection will pull seasonal temperatures into the 70s and 80s, it will also transport deep, tropical-like moisture into the area, yielding precipitable water values up to 1.80 inches. This environment will support widespread, hydro-efficient rainfall and embedded thunderstorms, with localized totals potentially exceeding 2.50 inches across portions of the CWA.

AVIATION

(For the 00Z TAFS through 00Z Friday evening) ISSUED AT 835 PM EDT THU MAY 21 2026

Showers and/or light rain persists in the wake of a frontal zone stalled to the south of eastern KY. Low clouds and or stratus build down fog was also common at issuance time with reductions to IFR in many areas and in some cases to near or below airport minimums. The boundary is expected to gradually lift north and into eastern KY as a warm front as the period progresses. This should lead to rounds of convection, but the low ceilings and IFR and lower reductions should be commonplace for the first 12 hours of the period north of the warm front. Then, gradual improvements into the MVFR ranges are probable to end the period. Some thunderstorms possible mainly during the last 6 to 9 hours of the period. Winds will remain light through the period, generally under 10 kts and primarily out of the northeast initially veering to southeast to south with time.

JKL WATCHES/WARNINGS/ADVISORIES

None.