912 FXUS63 KLMK 050550 AFDLMK Area Forecast Discussion National Weather Service Louisville KY 150 AM EDT Thu Jun 5 2025 ...Updated Aviation Discussion... .KEY MESSAGES... * Another warm and dry day. Rain chances increase after sunset west of I-65. * Active weather expected to return Thursday through Saturday. * Strong to severe storms possible in the Thursday through Saturday period, with Friday holding the greatest potential. * Excessive rainfall is possible as a surface boundary stalls across the region. 1 to 3 inches of rainfall could occur late this week and into the weekend resulting in localized flooding. && .SHORT TERM /THROUGH FRIDAY/... Issued at 244 PM EDT Wed Jun 4 2025 Diurnal Cu field was in full swing across the region this afternoon. A mix of mostly sunny but hazy skies was noted. Temperatures were being held down a bit by the Cu field as most locations were in the lower to middle 80s. For the remainder of the afternoon hours, no significant weather is expected. Afternoon highs of 83-88 are looking more likely at this time. Temperatures this evening will fall into the upper 70s. For tonight, skies will continue to cloud up as convective blowoff from the west pushes eastward into the region and a cold front draws closer to the area. Most areas look to remain dry overnight. We`ll have to watch for some weakening convection coming in from the west late tonight. Best chances of a shower or storm look to be across our far western areas where we`ll keep a slight chance of PoPs in the forecast. Lows tonight will be in the 65-70 degree range. For Thursday, a weak cold front will be located to our northwest and will continue to push slowly into the region. A broad area of showers and thunderstorms may be in progress across the region from the Ozarks through the Ohio Valley in the morning. Model soundings from across our region do show instability developing during the afternoon, but the CAM solutions are a bit all over the place with the amount of instability locally, depending on how much morning convection/cloud cover impact insolation. The CAMs do agree that better instability will be more confined to the mid south region from southern MO into northern AR. Background shear across the region remains quite weak with only 15-25kts of shear being predicted. In general, dynamical/kinematic profiles are strongly suggestive of multi-cellular clusters with a heavy rainfall and scattered damaging wind threat with any stronger cells. Highs on the day will be augmented by clouds/precip, though the majority of the guidance suggests highs of 82-87. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... Issued at 244 PM EDT Wed Jun 4 2025 Thursday Night through Saturday Night... For the Thursday night through Saturday night period, there remains little change in the forecast thinking here. Upper level trough axis flattens out and the flow aloft becomes a bit more zonal across the Ohio Valley. Aforementioned frontal boundary stalls out across the region on Friday as it becomes parallel to the upper level flow. The front will remain a foci for renewed convective development as multiple perturbations come through within the main flow aloft. The strongest one still looks to come through on Friday with another one coming through late Saturday night. For the day on Friday, convective evolution remains uncertain here, but the general consensus of the guidance suggests that a strong perturbation will move out of the Plains and head into the Ohio Valley late Friday and into early Saturday. Ahead of the disturbance, some atmospheric destabilization is expected and wind shear will increase across the region. Some sort of MCS looks possible here and arriving into our region near or just after peak heating. Model soundings show plentiful instability and greater shear that would again support heavy rainfall and damaging winds with the strongest cells. The tornado threat with this looks to remain low as shear profiles look rather unidirectional. Perhaps the best tornado potential would be along the southern edge of the MCS across southern MO and into far southwest KY/northwest TN. This activity should roll eastward Friday night. We may have a little break on Saturday as we`ll be in between perturbations, but another one looks to move into the region Saturday evening as the upper trough starts to sharpen up. This will allow the front to push on through the region late in the period. Again, depending on instability, some strong storms may be possible late Saturday. Highs during the period will be in the lower 80s with overnight lows in the 60s. Rainfall amounts of 1-3 inches will be possible by the end of the day on Saturday. Overall, the progressive nature of the rainfall and the expected breaks between waves may preclude more widespread hydro issues. However, scattered hydro issues are possible across the region, especially where storms may tend to train. Sunday through Wednesday... Upper level pattern will transition to a trough east, ridge west type pattern early in the period. A secondary wave looks to move through the region on Monday which could support yet another round of showers and thunderstorms, some of which could be on the strong side. After that, stronger upper level troughing will push into the region and send the frontal boundary from the weekend further east and southeast of the area yielding a drier and cooler forecast for Tuesday and into Wednesday. Highs Sunday and Monday will be in the lower 80s with overnight lows in the 60s. Highs on Tuesday and Wednesday will be in the upper 70s to around 80 in most spots while overnight lows dip into the upper 50s and lower 60s. && .AVIATION /06Z TAFS THROUGH 12Z FRIDAY/... Issued at 150 AM EDT Thu Jun 5 2025 The slow moving northeast to southwest oriented front is expected to remain northwest of southern Indiana and central Kentucky through the period, but ahead of the front, a line of precipitation is slowly working east towards area TAF sites. This line will first impact HNB within the next hour or so. A decent amount of lightning remains in the line, but the line is expected to weaken as it moves to the east overnight. MVFR ceilings are expected at HNB and could make it as far east as SDF before lifting. The chance remain low that MVFR ceilings make it to SDF before diurnal warming lifts ceiling, so VFR ceilings were left in the SDF TAF. This afternoon after some warming, more scattered thunderstorm activity is expected to develop and work east over the TAF sites. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...None. IN...None. && $$ SHORT TERM...MJ LONG TERM...MJ AVIATION...KDW