


Area Forecast Discussion
Issued by NWS Jackson, KY
Issued by NWS Jackson, KY
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066 FXUS63 KJKL 200517 AFDJKL AREA FORECAST DISCUSSION National Weather Service Jackson KY 117 AM EDT Tue May 20 2025 .KEY MESSAGES... - Shower/storm chances return at times tonight and linger through the middle of the week, mainly during the afternoon and evening hours. - There is a chance of strong to severe storms late tonight, and especially Tuesday afternoon into Tuesday night. There is also the chance for excessive rainfall late tonight through Tuesday night. - Highs will be near normal again on Tuesday, then are forecast to be below normal for Wednesday through Saturday. && .UPDATE... Issued at 1235 AM EDT TUE MAY 20 2025 With current forecast QPF exceeding 1 inch for most of the counties bordering TN and VA that were not in the initial flood watch issuance and to better correlate with the areal extent of the watch with surrounding offices and WPC Slight Risk ERO, opted to add those counties in to the watch and continue to leave Fleming County out at this time. Other than that only some minor adjustments were made to hourly grids based on observation trends. UPDATE Issued at 855 PM EDT MON MAY 19 2025 Minor adjustments were made to hourly temperatures based on recent observations trends. Overnight lows still are on track. Model runs will continue to be evaluated about the potential for Tuesday afternoon to early Tuesday evening storms to be equally as strong if not more so than anticipated later evening to early overnight round of storms closer to the cold front. The afternoon to early evening potential is contingent on heating following activity late tonight into the morning as the warm front lifts north. Areas near and west of I-75 && .SHORT TERM...(This evening through Tuesday night) Issued at 513 PM EDT MON MAY 19 2025 Late today, a closed upper low was over the northern plains, with a trough extending south. To the east of this, an upper ridge was situated a little east of the Mississippi River. Meanwhile, at the surface a warm front was over TN and extended to a low over the plains. The upper ridge will shift east over us tonight and the trough will begin to pivot around the upper low. This will support the surface low to track to the vicinity of IA by Tuesday, and to the Ohio Valley by Wednesday morning. This will pull the warm front north through KY on Tuesday and Tuesday evening, with the system`s cold front then approaching from the west by dawn on Wednesday. The warm air advection regime is expected to bring at least scattered showers/thunderstorms to the area by dawn and into the day Tuesday. As the negatively tilted upper trough pivots toward us and over the area late Tuesday and Tuesday night, additional shower/thunderstorms will occur. There have been some indications in today`s model runs that the shear/instability combo could become more favorable for severe wx. The SPC has increased the day 2 (Tuesday/Tuesday night) risk level for the JKL area, particularly for wind and tornadoes, with an enhanced risk now extending well northeastward to near KJKL. Activity should be on the decline overnight Tuesday night, but precip could linger past dawn. Lastly, repeated rounds of thunderstorms may bring localized excessive rainfall. With much of the area still wet from the last round of severe wx and flooding, problems could arise, and a Flood Watch was issued for Tuesday afternoon into Tuesday night for most of the forecast area. .LONG TERM...(Wednesday through Monday) Issued at 500 PM EDT MON MAY 19 2025 The models, and their individual ensemble suites, are in broad agreement aloft into the upcoming weekend before some discrepancies start to magnify into the start of the next week. They all depict a sharp, quick hitting trough working through the lower Ohio Valley on Wednesday with some slight 5h height falls for Kentucky as it passes along with a stream of mid-level energy skirting the northern part of the state. A secondary push of energy arrives that night extending the troughing down into Kentucky as the parent 5h low holds forth over the Great Lakes and Ohio Valley. Troughing then remains in place for this part of the country to start the weekend with northwest mid-level flow carrying a series of impulses through the area. The operational GFS is a bit stronger and further south with the core of this trough than the ECMWF. Ridging will then follow briefly for Sunday, as it builds in from the Southern Plains, but quickly another northern stream trough works this way from the Upper Midwest to start the new work week. The small model spread through Friday night supported using the NBM as the starting point with minimal adjustments needed - mainly to factor in some radiational cooling based terrain distinction in temperatures at night during the weekend. Sensible weather features some similarities to the pattern of last week. We will start out in the wake of storms passing through the area likely before dawn Wednesday with additional showers possible as a cold front moves through. Any drying in the wake of this will be short-lived, though, as the next wave works in with additional shower chances for Thursday. In fact, this potential also leads to a larger than normal spread amongst the models for Thursday`s highs. Quieter weather follows for the weekend thanks to high pressure but conditions will not be completely convection free or clear as the earlier boundary will start to work back northeast toward the area for the latter part of the weekend and, in particular, on Monday. This means a renewed chance of showers and storms for the area to start the new work week. Temperatures will be cooler than normal into the weekend with warmer and more normal readings to close out the period. The changes to the NBM starting point consisted primarily of adding enhanced terrain distinction to the temperatures for Friday and Saturday nights. As for PoPs - did not deviate from the NBM solution given the similar model solutions despite some of the upper level differences showing up in the latter part of the forecast period. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) ISSUED AT 105 AM EDT TUE MAY 20 2025 VFR conditions were reported at issuance time with some virga or light showers in parts of south central KY to middle TN to TN Cumberland Plateau upstream of KSME and KLOZ. A few storms were well west and southwest from IL into MO and AR. VFR is expected through the first 6 hours of the period, though during this time, isolated to scattered convection with the potential for brief MVFR reductions is possible generally from KLOZ and KSME south, with isolated to scattered convection spreading east and northeast to the remaining TAF sites through 13Z and then continuing north and northeast as a warm front nears eastern KY. The warm front lifts north across eastern KY during the 12Z to 00Z timeframe, the associated surface low enters the OH Valley toward 00Z and the trailing cold front approaches east KY at that point. A possible lull following morning to midday convection may occur with renewed and stronger activity after 16Z or 17Z possibly linear in nature with mainly a strong to damaging wind threat spreading across the area through about 23Z or 00Z. Additional activity should arrive from the west behind that second round. The strongest activity is more probable from KSME to KLOZ to KJKL and KSJS and points south where instability should be greatest. Some PROB30 groups were used to cover either potential for sub-VFR reductions in the showers/isolated storms in the first round between about 08Z to 16Z with additional PROB30 groups for the stronger storms in round two during he 18Z to 00Z timeframe. Also within those PROB 30 groups for KSME, KLOZ, KJKL, and KSJS, in addition to the potential for sub-VFR conditions also included wind gusts to 30 to 35KT, though some severe level winds gusts are not out of the question along with hail. Additional PROB30 groups were used to cover the last round of possible storms during the last 6 hours of the period. && .JKL WATCHES/WARNINGS/ADVISORIES... Flood Watch from noon EDT today through late tonight for KYZ050>052-058>060-068-069-079-080-083>088-104-106>120. && $$ UPDATE...JP SHORT TERM...HAL LONG TERM...GREIF AVIATION...JP