


Area Forecast Discussion
Issued by NWS Louisville, KY
Issued by NWS Louisville, KY
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719 FXUS63 KLMK 150705 AFDLMK Area Forecast Discussion National Weather Service Louisville KY 305 AM EDT Tue Jul 15 2025 .KEY MESSAGES... * Very warm and humid conditions are expected this week with scattered afternoon/evening thunderstorms. Torrential rainfall, gusty winds, and lightning will be the main threats with this activity. && .SHORT TERM /THROUGH WEDNESDAY/... Issued at 305 AM EDT Tue Jul 15 2025 A weak surface boundary has been slowly lifting northward across the region this morning. The boundary currently sits from just south of French Lick, IN to just south of Louisville and then trails southeastward to near Richmond, KY. A weak nocturnal low-level jet appears to be driving the overnight convection. Shear is weak across the region. However, PWAT values of greater than 2 inches reside in areas west of I-65. Between I-65 and I-75 PWATs were in the 1.8-2 inch range. Convection has been most focused across portions of Washington/Mercer/Boyle/Garrard counties this morning. Locally heavy rainfall of 1-2 inches has been observed via radar estimates and KY Mesonet observations. Temperatures remained mild across the region with readings in the lower-middle 70s. For the remainder of the overnight, aforementioned boundary should continue to lift northward across the region. Two main areas of convection are likely here. One will be the ongoing convection across east-central KY. This activity should continue to move eastward toward Richmond and may clip the southern end of the Lexington metro area later this morning. Second area of sustained convection will likely continue across our southwest IN counties of Crawford/Orange for the next few hours. Again, severe weather isn`t anticipated, but locally heavy rainfall will be possible with this activity. For today, the overall synoptic environment hasn`t changed all that much. Remnant convective complex is forecast to move northeastward toward the lower Ohio Valley this afternoon. Combination of this feature along with plentiful diurnal heating/destabilization is likely to support convective development across the region. Deep layer shear values remain less than 15kts or so through the threat of organized deep convection looks to be rather limited. However, with warm cloud depths of 12-14kft and PWATs over 2 inches, water loaded storms producing torrential rainfall, gusty winds, and frequent lightning will be possible. Highest concentration of storms looks to be across western KY closer to the remnant MCV coming into the region. Storm motions of 15-20 mph are expected and the main weather hazard today would be localized flooding where slow moving storms could lay down 1-2 inch amounts in some locations. Highs on the day will be similar to what we`ve seen in the past few days with readings in the upper 80s to the very low 90s. For tonight, we should see ongoing convection from the afternoon continue into the evening hours. Remnant MCV across western KY will continue to move eastward overnight and will be capable of producing some additional showers/storms into the overnight period. severe does not look all that great, but torrential rainfall, gusty winds, and lightning will be the main hazards with the overnight activity. Look for lows in the lower 70s once again. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... Issued at 305 AM EDT Tue Jul 15 2025 Longer range guidance for mid-week and beyond shows a rather stagnant upper air pattern across the CONUS. A short wave trough axis will move out of the Rockies on Wednesday and into the Plains, but it does not appear it will be close enough to us to influence our weather. In the meantime, look for diurnal instability to develop leading to scattered showers/storms in the afternoon/evening. Highs Wednesday will be in the upper 80s to the lower 90s with overnight lows in the lower 70s. By Thursday, the flow aloft continues to look low amplitude with the upper level ridge over the southeastern US spreading westward with increasing time. A rather slow moving frontal boundary looks to extend from roughly Ohio southwestward back into the southern Plains. Current progs do not suggest that this boundary will drop into our region. However, it will serve as a focus for additional shower/thunderstorm activity for Thursday. Model solutions at this time range continue to have a rather large variance. We`ll have ample instability during the afternoon, and with the frontal boundary close to the region, along with some lowering of the height field, overall convective coverage on Thursday looks to be a bit higher than Wednesday. Shear through this period may be a little higher as the band of westerlies dips into the region. Overall feeling here is that we could have some stronger storms on Thursday given the slightly better chance of organization. Gusty winds, heavy rainfall and lightning would be the main issues here. For Friday through the weekend and into early next week, the pattern looks to be potentially unsettled for much of the period. Sagging/stalled out frontal boundary to the north of the region will continue to be a focus for repeated rounds of convection. Will also have to watch how the upper level ridge to our south evolves over time. We`ll have some sort of tropical system that moves across the northern Gulf on the southern periphery of this ridge axis. Whether the moisture gets shunted off to the west toward TX or drawn more northward into the Ohio Valley remains in question. Overall, forecast will keep the same story of very warm and humid conditions with daily chances of showers/storms. Again, shear throughout the column looks to remain fairly weak. However, plentiful moisture will be available for storms to produce torrential rainfall, gusty winds and lightning. The potential for repeated rounds of storms may yield a flooding risk across portions of the region, especially areas that see repeated rainfall each day. QPF amounts of 2-3 inches through the period look likely, with locally higher amounts in some spots. Highs each day will be in the upper 80s to the lower 90s with overnight lows in the low-mid 70s. && .AVIATION /06Z TAFS THROUGH 12Z WEDNESDAY/... Issued at 124 AM EDT Tue Jul 15 2025 Notable surface boundary was located from just north of EVV to near FTK and then extends east over toward RGA. Scattered convection continues along this boundary this morning with the most concentrated area of convection just west of RGA. It`s possible that a few showers may reach SDF in the next 60-90 min as this boundary lifts northward. Rather stagnant airmass is expected to continue overnight with patchy fog developing across the region. Overall, most locations look to remain VFR overnight, though a drop to MVFR vsbys could occur with the patchy fog. Any fog that develops will be short- lived with VFR conditions returning to the region with a southwest breeze for much of Tuesday. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...None. IN...None. && $$ SHORT TERM...MJ LONG TERM....MJ AVIATION.....MJ