Area Forecast Discussion
Issued by NWS Jackson, KY
Issued by NWS Jackson, KY
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807 FXUS63 KJKL 071419 AFDJKL AREA FORECAST DISCUSSION National Weather Service Jackson KY 1019 AM EDT Sun Jul 7 2024 .KEY MESSAGES... - Seasonably hot and rain-free weather follows for today and through Monday morning before a humid and unsettled weather pattern develops during the new work week. - The remnants of Beryl will track to our northwest Tuesday into Wednesday, bringing an uptick in shower and thunderstorm activity. && .UPDATE... Issued at 1019 AM EDT SUN JUL 7 2024 High pressure and mid-level ridging will keep the weather quiet through through the day. This update was done to add in latest obs and trends and take fog out of the products. UPDATE Issued at 740 AM EDT SUN JUL 7 2024 No significant changes to the forecast in the near term other than just the inclusion of the latest obs and trends for the T/Td/Sky grids. These minor adjustments have been sent to the NDFD and web servers. && .SHORT TERM...(Today through Monday) Issued at 515 AM EDT SUN JUL 7 2024 08Z sfc analysis shows high pressure through the Ohio Valley and this is keeping the skies mostly clear over eastern Kentucky, aside from some lingering clouds in the far southeast. The lack of clouds for most of the area, along with light winds beneath the high, brought decent radiational cooling conditions in an airmass of relatively low dewpoints - at least compared to recent days. As a result, temperatures currently vary from the lower 60s in many sheltered valley spots to around 70 degrees on the hills. Meanwhile, dewpoints are generally in the low to mid 60s. Additionally, these conditions are also responsible for some fog in the river valleys early this morning. The models, and their individual ensemble suites, remain in decent agreement aloft through the short term portion of the forecast. They all depict ridging to the southeast dominating the weather for the area through Monday morning as 5h heights will be rising through then for eastern Kentucky. However by Monday afternoon, attention then turns toward the remnant circulation and moisture of former major hurricane Beryl as it rides into the lower Mississippi Valley - once picked up by the westerlies. This will help to start lowering downstream heights and also slip more energy into the persistent southwest mid-level flow. Yet, model consensus is to hold off any true impacts until Tuesday, at the earliest, for our area. Given the small model spread have again favored the NBM as the starting point for the forecast grids - along with some terrain based temperature enhancements early this morning and again tonight. Sensible weather features a warmer day, but humidity will be slower to climb sparing most of the area any heat index values above 95 degrees. This will likely not be the case for Monday when higher temperatures - in the low 90s for most - will combine with higher humidity to bring some heat index values to near 100 degrees across the area during the afternoon. It will also be in the afternoon that we will see a chance for showers and thunderstorms for the southeast third, or so, of the JKL CWA as the sfc high works away to the northeast. Tonight look for a smaller ridge to valley temperature split owing to slight higher dewpoints and a bit more cloud cover around. Again some river valley fog will be in the cards late tonight into early Monday morning. Again, the main changes to the NBM starting point consisted of adjusting the temperatures in order to better reflect more terrain details tonight. PoPs were not adjusted much spatially or in magnitude from the NBM as the CAMs where similar through Monday afternoon. .LONG TERM...(Monday night through Saturday) Issued at 515 AM EDT SUN JUL 7 2024 A seasonably strong ridge will start out aligned across the West, with a positively tilted trough positioned from Hudson Bay through the western Great Lakes/Upper Midwest and southern Plains. Meanwhile, Beryl will be closing in on the Arklatex region, while another ridge center remains over the southeastern CONUS. The models are in decent agreement through next week, with the remnants of Beryl eventually combining with the positively tilted trough to our west through mid-week. This trough will then gradually dampen by the end of the work week, with ridging and associated increasing 500 mb heights taking hold over the Tennessee and Ohio Valley into next weekend. Details associated with Beryl and its more specific impacts across eastern Kentucky still remain uncertain at this time. In general, the track remains to our northwest Tuesday into Wednesday. While the typical influx of anomalously high PWATs will occur, storm motions will be progressive. The low level flow will also be more southeasterly while the system is stronger. As such, the current model guidance does not show more concentrated higher QPF across eastern Kentucky. Still, at least isolated heavy rainers will be a possibility. Effective shears will also peak in the 30-35 kt range, coupled with more narrow CAPE profiles. This could allow for a few stronger storms, but will await further model guidance before including any more specifics at this point. PoPs will peak in the 40-60% range Tuesday night into Wednesday, as the core of the tropical remnants pass through, along with an associated surface cold front, and short wave energy aloft. Diurnally-driven PoP chances will then become more confined across southeastern Kentucky through the rest of the week, as the surface front stalls over the Appalachians. Tuesday looks to be the overall hottest day through the extended, with highs mainly in the lower 90s. This, coupled with dew points in the low 70s, will yield peak heat indices of around 100 degrees. Highs will then retreat to the mid and upper 80s for mid-week, with stormier conditions at play. A slight lowering of the dew points will occur on Thursday behind the cold front. Temperatures will then trend warmer into next weekend, with highs returning to around 90 degrees by Saturday, along with dew points nearing around 70 once again. && .AVIATION...(For the 12Z TAFS through 12Z Monday morning) ISSUED AT 750 AM EDT SUN JUL 7 2024 VFR flight conditions will hold through the period. Any lingering valley fog will clear out over the next hour with no impacts to any terminals. Late night fog tonight will also likely be limited to the valleys and also not affect any of the TAF sites. Winds will average around 5 kts or less through the period, generally from the northwest to northeast. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...DJ SHORT TERM...GREIF LONG TERM...GEOGERIAN AVIATION...GREIF