024 FXUS61 KILN 251815 AFDILN Area Forecast Discussion National Weather Service Wilmington OH 215 PM EDT Fri Jul 25 2025 .SYNOPSIS... Hot and humid conditions will keep the threat of high heat indicies and thunderstorms with torrential rainfall in the forecast for the next few days. A frontal boundary laying out over the region will act as a focus for storms this weekend. These high temperature values are expected to continue through mid-week. && .NEAR TERM /THROUGH TONIGHT/... Thunderstorm activity is expected to decrease significantly this evening, but then see an uptick overnight in west central Ohio. Threats from tonight`s storms will be the continued potential for torrential rains and isolated flooding where they hit poorly drained areas or maintain themselves over an area for any length of time. Lows from 70-75 will continue to add/accumulate stress on individuals who may suffer disproportionately from high heat index values, including but not limited to the elderly, poor, or those with serious medical conditions. && .SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/... Thunderstorm activity that should be isolated in the northwest during the early morning will see an uptick by late morning. This activity will become more scattered in nature and then become likely in the latter part of the day. This will be most noted north of the Ohio river where storms will occur at one point in time or another during the day. Once again, the primary threat with these storms lies in the potential for torrential downpours that have a high chance of creating localized flooding issues. The more persistent activity in the north where CAPEs >2000 J/kg stands a chance to combine with a favorable shear profile to produce potentially damaging winds in the afternoon. High temperatures will top out in the upper 80s/low 90s. Combined with a higher moisture environment, heat indicies will reach the upper 90s to near 100. A few points could top 100 but these will be the outliers. Overnight potential for thunderstorms will be focused more to the north along the I-70 corridor and then shift eastward to central Ohio. Another uncomfortable night with lows generally 73-75 are expected. && .LONG TERM /SUNDAY THROUGH THURSDAY/... Expansive mid level ridge centered over the southeastern US will retrograde into the central part of the country during the early part of the week. Peak height anomalies over the forecast area are still around 2 standard deviations on Monday. At the surface, a weak east- west oriented boundary is forecast to sag south out of the lower Great Lakes on Sunday. With plenty of moisture and instability in place, this will serve to enhance convective coverage. Locally heavy rainfall will continue to be the primary concern, although a few stronger downdrafts will also be possible. That boundary will likely dissipate by Monday leaving a more weakly forced environment for diurnal convection with a similar scenario for Tuesday. A pattern shift will take place later in the week. This starts on Wednesday when a lead short wave rounding the base of developing long wave trough tracks across the Great Lakes. This will drive a cold front across the region Wednesday into Wednesday night. NBM PoPs remain modest at this juncture which could be related to how low level forcing and mid level support align. Regardless, CSU MLP and CIPS analogs do highlight that day for some potential of severe weather. There is some uncertainty on Thursday whether the airmass will completely dry out or whether some showers will be possible as cooler air aloft spreads in. But there is a higher likelihood of drier conditions by Friday. Hot and humid conditions will persist for the first half of the week. Believe that NBM temperatures and dew points still have their slightly high bias, synergistically resulting in pretty high deterministic apparent temperatures. Probabilities of reaching heat advisory criteria of 100 are generally less than 30 percent area wide on Sunday. Probabilities increase across southern counties, 40 to 60 percent on Monday and 50 to 70 percent on Tuesday. Higher probabilities start to get shunted southwards on Wednesday, although still around 40 percent across northern Kentucky. Air temperatures will then fall below normal for the end of the week. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... Thunderstorm activity this afternoon may get a reinforcing shot of dynamics on the south side of a boundary that is primarily noted by the convection that has fired along it. This is likely at the intersection of increased CAPE values and increased theta-e values found in a wsw-ene orientation. That is, dynamic and ingredient based, not discernible in surface observations. Storms should remain se of Dayton, but upstream convection may eke further north than the convergent area they are firing on attm which will necessitate amendments if the trend over central IN increases as this location is currently covered by a prob30 starting at 22Z which looks to have the correct timing. Storms should remain n of Cinci/Lunken this afternoon but will maintain a closer eye on it as amendments will be necessary if convection pops further south of the better dynamics indicated by the boundary and location of current convection. Isolated activity remains possible this evening but coverage is sparse and will need to be amended into the fcst or noted with 00Z issuance. Some fog is possible at KLUK before daybreak. Scattered storms are expected to affect the region again on Saturday. This is covered by a late morning prob30. VFR conditions will prevail outside of LUK fog and any periods of thunderstorm activity. OUTLOOK...Showers and thunderstorms are possible through Monday, peaking in activity during the afternoon and early evening. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...Heat Advisory until 8 PM EDT this evening for OHZ063>065-070>074- 077>082-088. KY...Heat Advisory until 8 PM EDT this evening for KYZ089>100. IN...Heat Advisory until 8 PM EDT this evening for INZ066-073>075-080. && $$ SYNOPSIS...Franks NEAR TERM...Franks SHORT TERM...Franks LONG TERM... AVIATION...Franks