Area Forecast Discussion
Issued by NWS Louisville, KY
Issued by NWS Louisville, KY
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928 FXUS63 KLMK 302116 AFDLMK Area Forecast Discussion National Weather Service Louisville KY 416 PM EST Sun Nov 30 2025 .KEY MESSAGES... * A storm system will move through the region Monday night into Tuesday morning, bringing mixed precipitation types as it crosses the area. * Accumulating snow is likely across portions of the area, especially along and north of the WK/BG Parkways. Most likely snowfall amounts within this zone are around 1-3". Brief periods of freezing rain/sleet are possible, and a glaze of ice is possible before changing to snow. * Impacts to travel conditions are likely Tuesday morning. && .SHORT TERM /THROUGH TONIGHT/... Issued at 415 PM EST Sun Nov 30 2025 This Afternoon and Tonight... Sfc low pressure is over southern Ontario this afternoon, with a cold front extending to the south along the Appalachian Mountains. High pressure over the Dakotas will gradually slide to the east this evening, allowing another reinforcing cold air mass to filter into the region from the northwest. As the sfc low lifts away from the region, winds should settle, with breezy W/NW winds this afternoon becoming light and veering to the N/NE overnight. While most of the area has seen clouds scatter out today, a large stratus layer is immediately to the north of the area. As we head through the rest of the evening, clouds are likely to fill in across southern IN and northern KY, with less cloud cover expected along and south of the Parkways. Tonight, dry and cold conditions are expected, with a mixture of clear skies and low clouds expected across the area. Where more clearing occurs, likely over southern and southeast KY, temperatures should be able to fall into the low 20s, with upper teens also possible. Where there are more clouds, temperatures will likely remain in the mid-to-upper 20s. Regardless, it will be a cold start to Monday morning with temperatures in the 20s in most areas. Monday... Most of the daytime hours on Monday will feature uneventful weather with cool and dry conditions expected to continue until at least late afternoon. Highs on Monday are expected to range from the upper 30s across southern IN to the mid-to-upper 40s across southern KY. High pressure to the north of the area during the morning will end up over the northeast US by Monday evening as low pressure develops and builds northward out of the western Gulf. This area of low pressure is being supported by an upper-level trough which will eject out of the central Rockies and across the Plains during the day on Monday. Mid- and upper-level height falls along and west of the Mississippi Valley Monday into Monday evening should lead to increasing SW flow into the TN and lower Ohio Valley, providing a source of richer moisture. A plume of anomalously high PWATs, generally between 0.75-1", should advect into the region Monday afternoon into Monday night. Monday Night - Tuesday Morning Winter Weather... By Monday evening, precipitation should begin to move northward across TN within the WAA/moisture advection regime. At the same time, a band of light-to-moderate precipitation associated with ascent along and ahead of the upper-level trough axis should approach the region from the west-northwest. While there will initially be a dry slot between these two features, there is increasing confidence that moisture from the sfc low and low-level warm advection regime and better synoptic-scale lift from the approaching upper trough will collide over the area, resulting in a band of moderate to heavy precipitation moving across the area early Tuesday morning. Cross-section profiles support the thinking of heavier banded precipitation with strong 850-700 mb frontogenesis and theta-E profiles showing relatively weak stability within the DGZ. It continues to look like a mixed bag of precipitation types are likely with this system. Within the initial surge of precipitation, warm advection should lead to many areas seeing rain, especially along and south of the WK/BG Parkways. A brief period of freezing rain/sleet cannot be ruled out on the northern/northwest fringe of the warm advection zone; however, little more than a glaze of ice is expected at this time, and marginal ground temperatures should limit icing on roadways. Once we get on the back side of the sfc low, cold advection aloft combined with wet-bulbing effects within zones of strong lift should lead to precipitation changing to all snow before ending. The areas which see the greatest snowfall amounts should be the ones which have the greatest overlap between favorable thermal profiles and best forcing/moisture availability. At this time, the forecast calls for a band of 1-2" of snow roughly along and north of the WK/BG Parkways, with isolated pockets up to 3" likely where the heavier banding sets up. South of the Parkways, less than 1" is currently forecasted; however, given the high boom/bust potential in banding-type events, would not be surprised given the latest hi-res runs if the potential for 1+" snow increases in subsequent forecasts. Because of the increased uncertainty and still being ~30 hours away from the start of this event, we`re going to hold off on issuing any headlines. However, if current forecast trends hold, a winter weather advisory will likely be needed for much of the forecast area, especially along and north of the Parkways. While precipitation should begin shortly after sunset Monday, the time window for the greatest winter precipitation accumulations should be from around Midnight until dawn Tuesday. This could lead to notable impacts to travel even if lesser amounts are realized given the proximity to the Tuesday morning rush. && .LONG TERM /MONDAY THROUGH SUNDAY/... Issued at 415 PM EST Sun Nov 30 2025 Tuesday Afternoon through Thursday... After the early week system departs the region Tuesday morning, quieter weather is expected during the mid-week period. While clouds will likely linger in the wake of the Tuesday system, clearing skies are expected on Wednesday as high pressure moves across the region. Temperatures will continue to be cold during the mornings, with lows in the teens and low 20s expected Wednesday morning. High temperatures on Wednesday should be able to warm into the upper 30s and low-to-mid 40s as we get weak return flow into the area ahead of an approaching front. The cold front, which we will be on the southern edge of, should pass through the region without much fanfare as the better moisture and forcing with this system will be well to the northeast of the region. However, we should see some extra clouds with cold FROPA Wednesday night into Thursday morning. Another area of high pressure should drop into the Midwest on Thursday, dropping temperatures as NW flow moves over the area on Thursday. Thursday Night through Saturday Night... A fairly similar setup to what we`ll experience tomorrow into tomorrow night is expected to return Thursday night into Friday, as a shortwave upper trough ejects across the central CONUS, pulling a developing surface low northward out of the Gulf and into the TN/lower OH valleys. The cold air source ahead of this system does not appear to be as supportive of wintry weather as the one tomorrow night, with the center of the sfc high shifting off the mid-Atlantic Coast. However, given the amount of lead time and potential shifts in the model guidance, we`ll need to continue to monitor this system later this week for wintry weather potential. Forecast confidence decreases after Friday, though a general signal for additional disturbances swinging through the region later in the weekend is found in the medium-range guidance. A modest warming trend over the weekend should make it more likely that these systems end up being mostly/all rain. However, temperatures should remain below normal through next weekend. && .AVIATION /18Z TAFS THROUGH 00Z TUESDAY/... Issued at 1239 PM EST Sun Nov 30 2025 Through the current TAF period, the main concern will be CIGs as a lingering stratocu field tries to scatter out. With cloud bases generally between 2-3 kft, categories may bounce between MVFR and VFR this afternoon into tonight. Winds should steadily ease this evening and veer from the W/NW to the NE overnight. Confidence in whether we`ll see VFR/MVFR CIGs overnight is fairly low as stratus may try to fill in. SDF/LEX/HNB have the best chance for MVFR CIGs with BWG/RGA having lesser chances. Monday morning, VFR conditions are expected at all sites as long as the low-level stratus scatters out as expected. Winds should be around 6-12 kt out of the east tomorrow. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...None. IN...None. && $$ SHORT TERM...CSG LONG TERM...CSG AVIATION...CSG