401 FXUS63 KJKL 110235 AFDJKL AREA FORECAST DISCUSSION National Weather Service Jackson KY 1035 PM EDT Wed Oct 10 2018 .UPDATE... Issued at 1035 PM EDT WED OCT 10 2018 The latest scans of the regional WSR-88D radars shows a line of showers and isolated thunderstorms continues to slowly progressing east across central Kentucky tonight. The hires guidance suggest this will become more diffuse before regenerating, as it moves into portions of eastern Kentucky towards dawn. Given this updated grids to better reflect the latest trends, but for the most part this will be a fairly minor update to the grid set as a whole. We are starting to see some interaction with the approaching upper level synoptic system and the tropical system to our south. It still looks like the better chances of heavier rainfall will reside across portions of the Tennessee Valley and points southeast of that. Even so, will continue to watch trends through the night as the potential for ample moisture returns. Updates to the grids have been sent. UPDATE Issued at 743 PM EDT WED OCT 10 2018 The latest scans of the regional WSR-88D radars shows a line of showers and isolated thunderstorms are slowly progressing east across central Kentucky this evening. Most of eastern Kentucky is dry this evening, but we have seen a isolated shower develop from time to time ahead of the approaching cold front. We will watch this broken line of showers move into the region later this evening into tonight. This along with a upper level jet and enhanced moisture from the tropical system to the south will lead to increased coverage of rain overnight into Thursday. The best coverage will be across eastern and far southeastern portions of Kentucky. This was well denoted in the grids, but made minor tweaks with the latest trends in the guidance. We are still in a marginal risk for excessive rainfall in the far southeast, but the overall higher risk for more enhanced rainfall will be southeast toward the Tennessee Valley. However, it will need to be monitored tonight given the enhanced moisture and exiting upper level jet towards dawn. && .SHORT TERM...(This evening through Thursday night) Issued at 416 PM EDT WED OCT 10 2018 Short term portion of the forecast will be focused around an incoming cold front. Strong southerly flow ahead of the frontal passage led to morning showers across the region, which have now moved north of the CWA. Scattered to numerous clouds remain across the CWA, with another swath of rain expected to move in later this afternoon/evening nearer to the actual frontal passage. There will be a narrow window of instability this evening as it moves through, so did keep with thunder mention through the evening, cutting it off after 6Z, though there isn't enough to be concerned for any strong or severe storms. WPC is highlighting far eastern Kentucky as having the potential for heavy rain as the system moves through between 6 and 12Z tonight, with over 0.5 inches of rain possible. Though we are not expecting any flooding concerns, especially given several days of drying across the region, we will need to monitor this rainfall overnight in case there is some isolated concerns. Once the front moves through Thursday morning, pops will decrease from west to east, with all pops out of the CWA by Thursday evening. A much colder airmass will move in behind this frontal passage. After being above normal in temperatures for an extended period of time, we are now taking the turn to below normal temperatures. Highs on Thursday will range from the mid 60s to around 70 degrees. With clearing expected overnight Thursday night, temperatures will likely drop extensively, into the low 40s. .LONG TERM...(Friday through Wednesday) Issued at 406 PM EDT WED OCT 10 2018 The majority of the long term period will feature an upper level CONUS-wide northern stream trough, with several progressive shortwaves. Dry conditions will dominate the first part of the extended until early Saturday morning. Rain chances will increase for areas north of the Mountain Parkway due to the passage of an upper level shortwave. A period of dry weather will then take hold again until a cold front approaches the Commonwealth Sunday afternoon. The best precipitation chances will be with the passage of this cold front Monday morning. The front will exit eastern Kentucky, ushering in drier conditions for Tuesday. Another upper level disturbance and surface cold front are slated to move through the Ohio Valley midweek, but uncertainty in this portion of the forecast is high due to model disagreement. High temperatures will generally be in the upper 50s, low 60s for the duration of the extended. Low temperatures will mainly be below normal through the period. However, Monday morning lows will increase to be near normal. The lowest temperatures expected for the period will occur Tuesday morning, dipping to the mid 30s in areas near the Bluegrass and in parts of the Cumberland Basin. These areas have the potential to see some frost as well. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) ISSUED AT 722 PM EDT WED OCT 10 2018 Most locations are dry this evening as we remain ahead of a westward moving cold front. We are watching a broken line of showers and isolated thunderstorms develop ahead of the front across central Kentucky this evening. This line will slowly progress east through the evening and into tonight. This coupled with moisture from the tropical system to the south will lead to an increase in rain showers tonight into Thursday. TAF wise we will see chances of MVFR conditions for both CIGs and VIS tonight into early Thursday, with heavier showers and isolated thunderstorms. We do see the possibility of worsening CIGs toward dawn, but improvements back to VFR will come by Thursday afternoon. We are seeing southeast flow this evening before veering to southwest through much of the night. Then the front will allow winds to veer even more to the west and northwest through the day Thursday. We could see some gusts of 15 to 20 knots mainly in the Lake Cumberland and Bluegrass regions by early Thursday into Thursday afternoon. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...DJ SHORT TERM...JMW LONG TERM...CGAL AVIATION...DJ