085 FXUS63 KILX 232343 AFDILX Area Forecast Discussion National Weather Service Lincoln IL 643 PM CDT Thu May 23 2019 .SHORT TERM...(This evening through Friday) ISSUED AT 331 PM CDT Thu May 23 2019 20z/3pm surface analysis shows a nearly stationary frontal boundary draped along the I-70 corridor. While radar remains clear for the time being, latest visible satellite imagery is showing a Cu field trying to develop near the boundary. Several CAMs suggest isolated thunderstorms will fire across this area over the next few hours...with better areal coverage expected further south into the highly unstable warm sector near the Ohio River. Will therefore carry slight chance PoPs along/southeast of a Paris to Shelbyville line for the remainder of the afternoon into the early evening. The front will begin to lift back northward late tonight in response to short-wave ridging ahead of an approaching upper low. While the primary nocturnal jet will focus across the Plains, 850mb winds will increase to 30-40kt across west-central Illinois late tonight. As a result, think the best chance for showers and thunderstorms will materialize west of I-55 after midnight. Convection will then shift to along/north of I-74 by Friday morning before exiting into the southern Great Lakes toward midday. Much of Friday looks to be very warm/dry, as focus for late day convection appears to be across southern Wisconsin into central/eastern Iowa. These storms will then gradually shift E/SE into the N/NW CWA late Friday night into Saturday morning. .LONG TERM...(Friday night through Thursday) ISSUED AT 331 PM CDT Thu May 23 2019 The warm/unsettled weather pattern will continue through the Memorial Day weekend...with periodic storm chances each day. Thunderstorms will be ongoing across the northern half of the KILX CWA Saturday morning, with scattered storms re-developing further south along the residual outflow boundary during the afternoon/evening. A short-wave trough ejecting out of the Plains will enhance the areal coverage of the storms late Saturday night into Sunday morning...followed by a relative lull in precip chances Sunday afternoon through Monday as upper ridging builds sufficiently to shift the convective focus further N/NW. After that, the next significant chance for showers and thunderstorms will arrive Tuesday night into Wednesday as another stronger wave breaks down the prevailing SE CONUS ridge and pushes a cold front into the area. While severe weather will be possible through the entire period, it is still too early to pinpoint exact timing/threats. Confidence is higher concerning the potential for locally heavy rainfall through early next week...with current indications focusing the highest amounts of 1-2 inches along/northwest of the Illinois River. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 643 PM CDT Thu May 23 2019 VFR conditions this evening then scattered showers and thunderstorms as a frontal zone to the south of central IL begins to lift northward into the area. SHRA/TSRA activity is expected to begin from 07-09Z until 12-16Z, with a low probability of continuing later, especially KPIA northwestward. A period of MVFR cigs is expected to develop from 10-12Z and continue for a few hours before cigs increase after sunrise. Winds NW under 8 kts gradually turning to NE to E overnight. Winds continuing to turn to S-SW by 16Z, and increase to 10-14 kts with higher gusts to 20 kts by around 18Z. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Barnes LONG TERM...Barnes AVIATION...37