


Area Forecast Discussion
Issued by NWS Jackson, KY
Issued by NWS Jackson, KY
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175 FXUS63 KJKL 080434 AFDJKL AREA FORECAST DISCUSSION National Weather Service Jackson KY 1234 AM EDT Tue Jul 8 2025 .KEY MESSAGES... - High temperatures will return to near normal through the week as humidity increases. - Chances for shower and storms persist through the upcoming weekend, mainly during each afternoon and evening. && .UPDATE... Issued at 1147 PM EDT MON JUL 7 2025 Made small changes to PoPs and Sky cover in addition to initializing the temperature forecast with the latest observations. There are no changes to the short-term forecast and forecast reasoning. UPDATE Issued at 834 PM EDT MON JUL 7 2025 Made a small update to PoPs through midday Tuesday. Convection has developed this evening as a low-level jet has developed, which seems to be well forecast by the GFS. The warm advection associated with this low-level jet will likely keep at least isolated showers and thunderstorms going across the northwestern half of the forecast area through the overnight. Nevertheless, can not completely rule out activity across any part of the forecast area through Tuesday morning. UPDATE Issued at 654 PM EDT MON JUL 7 2025 Increased PoPs to keep low-end (i.e., slight chance) in the grids and text forecasts through tonight given an approaching front, weak disturbance aloft, and continuing warm advection through the overnight as indicated by forecast low-level wind increases just above the surface inversion over eastern Kentucky. No other significant changes were made with the early evening update. && .SHORT TERM...(This evening through Tuesday night) Issued at 252 PM EDT MON JUL 7 2025 A pattern shift has occurred across the CONUS as the upper-level ridge, which had brought warm and dry conditions, has broken down. Surface high pressure still persists over the southeastern US; however, a cold front is slowly tracking toward the CWA from the northwest. Locally, showers and thunderstorms have already developed ahead of this approaching boundary, and southwesterly flow continues to advect warmer temperatures into eastern Kentucky. This southwesterly flow has allowed temperatures to climb into the upper 80s, approaching the lower 90s. A weak upper-level trough will pivot overhead through the CWA tonight, but the primary forcing for the surface low responsible for the cold front is situated over the Canadian Maritimes. Upper-level forcing abandons the front, which is expected to stall along the Ohio River later today. This will keep the CWA on the warm side of the front, with highs climbing into the lower 90s. Additionally, sufficient lift is in place to allow for the development of widespread showers and thunderstorms. The severe thunderstorm threat appears marginal due to weak effective bulk shear values; however, there is upwards of 1,100 J/kg of DCAPE, leading to the potential for gusty outflow winds. Showers and storms will taper off toward sunset, leading to a dry overnight. Overnight lows will be in the upper 60s to lower 70s, with areas of valley fog and fog developing from todays rainfall. Tuesday will feature similar weather to Monday, as the baroclinic zone remains stationary, and the threat for strong storms develops again Tuesday afternoon. Highs are forecast to climb into the upper 80s to lower 90s, with widespread convective activity expected. Again, effective bulk shear values remain marginal, but DCAPE values are high once more, and gusty outflows are expected. Showers and storms will once again dissipate toward the late evening hours. Expect another night with lows in the upper 60s and lower 70s, accompanied by areas of fog. Overall, an active forecast period is expected due to a stalled frontal boundary. Afternoon convection is anticipated each day, with highs in the upper 80s and low 90s. Each night will feature overnight lows in the upper 60s and low 70s, along with areas of fog. .LONG TERM...(Wednesday through Monday) Issued at 400 PM EDT MON JUL 7 2025 The period is expected to begin with an upper level low over Ontario and an associated trough south through the Great Lakes to OH Valley to the Arklatex to western Gulf between an upper level ridge centered near Bermuda and another upper level ridge centered over the Southwest Conus. Guidance continues to have a shortwave trough moving through the upper trough and across portions of the OH Valley as the period begins while upper level trough should extend from an upper level low in western Canada into the Northwest Conus to CA. At the surface, a ridge of high pressure is expected to extend from the Gulf of Mexico into the Southern Appalachians with a frontal zone extending from off the Northeast Coast to the mid Atlantic sates to a surface low in the Great Lakes and then southwest and west to the mid MS Valley to Central Plains. Another sfc system should be in advance of troughing in western Canada and centered in Saskatchewan with a warm front extending into the northern Plains and a cold front across southwest Canada. Early on Wednesday, PW per the 12Z HREF mean is forecast generally the 1.5 to 1.8 inch range a bit above normal for this time of year nearer to the 75th percentile. From Wednesday to Thursday night, the upper level low is expected to move into Quebec with the northern portion of the trough shifting into the Northeast to Mid Atlantic states through the axis of troughing at 500 mb nears but generally remains west of eastern KY. A couple of shortwave troughs are progged to cross eastern KY during this time, one Wednesday to Wednesday evening with another crossing the area about Thursday. As this occurs, upper level ridging should remain centered in the western Atlantic in the vicinity of Bermuda while upper level ridging remains from the Southwest Conus/northern portions of Mexico into the eastern Pacific. Meanwhile, upper trough should advance east toward Central portions of Canada/Hudson Bay southwest to the Northern Rockies crossing the Great Basin. Meanwhile, at the surface, as the trough moves into eastern Canada and toward the Northeast, the boundary north of eastern KY is expected to sag south of the Great Lakes and extend from the mid Atlantic coast to OH to north of the Ohio River to the next sfc system in the Plains. With the trough axis near or west of eastern KY during this period, convection cannot be ruled out at any point, with coverage likely to peak each afternoon and evening. Valley fog should continue to be a fixture each night to early morning and would be more widespread or dense if clearing at night were to follow a period of heavier rainfall. With the trough in place/come cooling aloft cloud cover and precipitation should keep highs nearer if not slightly below normal for this time of year. Friday to Saturday night, some height rises are anticipated across the Southeast for Friday into Saturday as an upper level low organizes near the US/Canadian border near the Ontario/Manitoba border to Northern Plains/Upper MS Valley areas with troughing developing/moving into the Central Conus. During this time, upper level ridging should remain in place across much of the western Conus. At the surface, low pressure is expected to trek from Manitoba toward the Hudson/James Bay region with the trialing front advancing across parts of Ontario and into the Central Great Lakes to mid MS valley to portions of the Plains. At the same time, a sfc ridge of high pressure is expected to generally remain from the Gulf into the Southeast/Southern Appalachians. The region will remain in the warm sector with convection possible through the period, generally each afternoon and evening. Sunday to Monday, upper level ridging is expected to remain from the Southeast/Gulf of Mexico and across the Southwest Conus as the upper low in Canada is progged to weaken and move toward Hudson and James Bay. The shortwave trough to the south is generally forecast to advance east across the Great Lakes and toward the Northeast with run to run variability with timing and strength. Another shortwave should also have moved across western Canada and US/Canadian border. With the shortwave trough generally passing north of the region, the surface low in Canada should move into Quebec/eastern Canada with the trailing sfc front may become diffuse with southern/southwest extent. Meanwhile, a ridge of sfc high pressure should persist from the Gulf to the Southeast. With no clear features to time for more organized convection at this point, diurnal peaks in convection are anticipated to begin next week as well. Temperatures per guidance should be near normal. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) ISSUED AT 1232 AM EDT TUE JUL 8 2025 Continuing warm advection in part fueled by a low-level jet will keep occasional clouds and isolated showers and storms in the forecast through the remainder of the overnight, though confidence is too low to include a mention for any specific terminals at this time, though KSYM stands the best chance of seeing such isolated shower/storm activity. KSYM may also continue to see intermittent MVFR reductions due to fog from earlier showers and storms, with the other terminals anticipated to remain free of fog concerns. Shower and thunderstorm activity is expected to increase again areawide around midday Tuesday, and last into the late afternoon or early evening. South to southwesterly sustained winds around 10 knots are expected through the afternoon before becoming light and variable overnight. Used PROB30 groups to cover the shower/storm potential for now. && .JKL WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...CMC SHORT TERM...VORST LONG TERM...JP AVIATION...CMC