textproduct: Paducah

KEY MESSAGES

- Warmth continues to end the weekend with highs in the lower 80s. An isolated shower or thunderstorm cannot be ruled over the Ozark Foothills this afternoon.

- A significant severe weather episode remains possible Monday afternoon and evening.

- Another round of showers and thunderstorms will be possible Tuesday afternoon and night.

- Much cooler temperatures and dry weather arrive Wednesday and continue through next weekend.

DISCUSSION

Issued at 306 AM CDT Sun Apr 26 2026

A very deep mixed layer(6kft) will lead to a warm and dry day for the Quad State today. There may be just enough instability to support a brief shower or thunderstorm over the Ozark Foothills in the afternoon. The shear is very weak, so any storms should be short-lived and weak, but they could produce some gusty winds. Severe weather is not expected.

The 00Z guidance continues to develop a very concerning severe weather environment over the Quad State Monday afternoon and evening. CAPE of 2000-4000J/kg is expected to develop over the western half of the region, while 0-3km SRH values climb to the 300-400m2/s2 range. Much of that SRH is in the lowest kilometer, leading to a significant tornado risk. The best instability is expected in the west and the best shear will be in the north, while the weakest instability and shear will be in the southeast.

Convective initiation continues to be a source of uncertainty, but the general consensus is that warm advection forcing will wipe out the cap and allow for widespread thunderstorm development in the late afternoon and through the evening. If the storms are still discrete supercells when they develop over or reach th1e area, significant, long-track tornadoes will be possible, along with very large hail (2+"). If and when the storms form into a line, the tornado risk will continue both with embedded supercell potential and spin up potential with mesovortices along the line. EF-2 tornadoes would still be possible with the line. That said, widespread damaging winds would become the dominant severe weather threat.

The CAMs are now giving us a more detailed look at the event through Monday. The new RRFS even goes through Monday night. It is quite concerning that the HREF and RRFS hold off most of the development until after 00Z (possibly after 03Z) and keep the coverage more in the isolated to scattered range. Of course, this would lead to discrete supercells potentially over the entire area, and could push the event into the overnight hours in the east.

The bottom line is that the focus for this event is likely to be to our north from northeast Missouri through central and northern Illinois. This area has the best low-level convergence, upper support, and shear. The uncertainties in convective initiation, timing, coverage, and mode remain across the Quad State. Hopefully, additional CAM data will bring increased confidence in these details over the next 24 hours.

The cold front will stall out over the Quad State behind the Monday system, and the 00Z guidance continues to develop a surface wave and push it northeast through the Quad State Tuesday afternoon and evening. Moderate instability and increasing shear may be sufficient to support another severe weather threat. The exact path of the surface low through the area is not certain at this time, and its path will be the northwest edge of the general thunderstorm and severe threat. For now, it looks like most, if not all, of the region could be impacted. The low-level shear will not be as strong, so this would be a damaging wind and large hail event.

In the wake of this system, surface high pressure will build over the Quad State with cyclonic northwest flow aloft expected to continue through next weekend. That will lead to a nice cool down to below normal levels to go along with dry weather.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 620 AM CDT Sun Apr 26 2026

An area of IFR or low MVFR ceilings over southwest Indiana is steadily moving southwest and may impact KEVV and KOWB for a few hours this morning. Planning on them arriving by 13Z and dissipating by 16Z at both sites. Otherwise, the TAFs are VFR. Any convection this afternoon or late tonight will remain well west of KCGI.

PAH WATCHES/WARNINGS/ADVISORIES

IL...None. MO...None. IN...None. KY...None.