475 FXUS63 KILX 090830 AFDILX Area Forecast Discussion National Weather Service Lincoln IL 330 AM CDT Sun Jun 9 2019 .SHORT TERM...(Today and tonight) ISSUED AT 329 AM CDT Sun Jun 9 2019 Upper low over the Ohio River Valley will continue to be the main weather-maker today...providing plenty of cloud cover and a few showers. 08z/3am regional radar mosaic shows widespread showers across central/southern Indiana pivoting N/NW toward east-central Illinois. With the low lifting slowly northward, the best rain chances will likely be confined to locations along/east of the I-57 corridor where high chance to likely PoPs are warranted. Further west, areal coverage will be considerably less across the remainder of the KILX CWA. While instability will initially be negligible, SBCAPEs will increase to 500-1000J/kg this afternoon, supporting at least isolated thunder. Thanks to ample cloud cover and scattered showers, highs will be several degrees cooler than yesterday...with afternoon readings topping out in the upper 70s and lower 80s. Scattered showers will linger through this evening before an approaching cold front pushes any remaining precip into Indiana overnight. Once the front passes, brisk northwesterly winds will develop late tonight as lows range from the middle 50s west of the Illinois River...to the middle 60s south of I-70. && .LONG TERM...(Monday through Saturday) ISSUED AT 329 AM CDT Sun Jun 9 2019 The pressure gradient between the departing cold front and a high building into the Plains will tighten sufficiently to produce W/NW wind gusts of 30-35mph on Monday. Despite full sunshine, strong CAA will keep temperatures in the middle 70s. After a chilly night with lows in the lower 50s, the airmass will moderate on Tuesday as highs rise into the upper 70s to around 80 degrees. The upper air pattern for the remainder of the extended will feature anomalously low heights as a short-wave diving out of Canada carves a significant trough over the Great Lakes/Ohio River Valley. Scattered showers and thunderstorms will develop in advance of this feature late Tuesday night into Wednesday, followed by a return to cooler/drier conditions for Thursday and Friday. 00z June 9 models are in good agreement with the timing/strength of the wave, with both the GFS and GEM showing the 555dm 500mb height line dropping into central Illinois by 12z Thu. With corresponding 850mb temps of 4-6C, low temperatures may dip into the upper 40s in some locations Wednesday night. Further out, some key model differences arise as the operational GFS digs yet another short-wave southward into the region on Friday...while the GEM/ECMWF are more progressive with the upper trough shifting eastward. The operational GFS is the odd model out at this point, as the GFS Ensemble supports the more progressive GEM/ECMWF solution. As a result, think heights will rise and temps will rebound by next weekend with highs back into the 80s by Saturday. && .AVIATION...(For the 06Z TAFS through 06Z Sunday night) Issued at 1128 PM CDT Sat Jun 8 2019 Showers have diminished in coverage late this evening across central Illinois and anticipate dry conditions to prevail overnight into much of Sunday morning. The chance for scattered showers will increase again with daytime heating and under the influence of an upper low over the region late morning through the afternoon. Precip coverage should be greatest near the IL/IN state line, but isolated to widely scattered near the terminals. The other main concern will be ceilings, especially late tonight and through the day Sunday. MVFR ceilings are already occurring along portions of the Ohio Valley and in southern Indiana and are expected to spread and expand northwest across central Illinois late tonight into Sunday morning. Models are not consistent in handling the low moisture and have trended less pessimistic with ceilings heights and slower timing...thus confidence in the details remains low and will have to monitor observational trends overnight. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Barnes LONG TERM...Barnes AVIATION...Deubelbeiss