329 FXUS63 KILX 130447 AFDILX Area Forecast Discussion National Weather Service Lincoln IL 1147 PM CDT Thu Oct 12 2017 .UPDATE... Issued at 845 PM CDT Thu Oct 12 2017 The extensive low cloud deck remains over the area this evening however the evening sounding shows it to be only a few hundred feet thick at this time and satellite imagery shows a break in cloud cover from Bloomington through Paris, and a back edge from Quincy to Litchfield moving northeastward. Clearing behind the back edge should result in patchy fog forming as radiational cooling increases, and is depicted by several runs of the HRRR and other models. Main update tonight, then is to add patchy fog to southern and western portions of the forecast area. Otherwise, lows in the lower 50s and light southerly winds look good for tonight so have made no changes to temperatures and winds. && .SHORT TERM...(This evening through Friday) ISSUED AT 315 PM CDT Thu Oct 12 2017 Extensive deck of low stratus clouds continue to blanket IL/IN and into eastern IA and northeast MO at mid afternoon. These clouds trapped in a strong inversion under nearby high pressure ridge to our northeast and light winds which will likely keep skies cloudier into tonight. Could even be some patchy fog and drizzle again overnight into early Fri morning especially in east central IL where low clouds linger into Fri morning. Lows overnight in the lower 50s, with some mid 50s in east central IL. An increasing southerly flow on Friday should help break up low clouds as skies become partly sunny and temperatures to warm up to 75-80F Fri afternoon. A frontal boundary setting up from central KS ne to along the IA/IL border will initially keep chances of convection nw of CWA during the day on Friday. .LONG TERM...(Friday night through Thursday) ISSUED AT 310 PM CDT Thu Oct 12 2017 The frontal boundary will get closer to our nw counties on Fri night, bringing isolated convection to areas nw of the IL river Fri night after sunset. Then a better chance of convection spread se across areas north of I-72 overnight Fri night into Saturday, with likely pops over the IL river valley. Lows friday night in the upper 50s and lower 60s, coolest readings in eastern IL. Unseasonably warm highs in the low to mid 80s on Saturday except upper 70s over far northern CWA. Surface low pressure to eject ne from central KS into west central WI by sunset Saturday and deepen ne of the Great Lakes by sunrise Sunday. This to push the cold front se across CWA during Sat night. SPC day3 outlook has marginal risk of severe storms nw of I-55 while slight risk is just west of Knox, Fulton and Schuyler counties for Sat night. 12Z models are in better agreement with quicker exit of cold front on Sunday and have trended pops downward on Sunday morning with dry conditions over IL river valley, likely pops in southeast IL early Sunday, then dry across area by Sunday afternoon. Breezy nw winds bring in much cooler air on Sunday with highs ranging from upper 50s and lower 60s over IL river valley, and upper 60s in southeast IL. Seasonably cool lows in the lower 40s Sunday and Monday night, with a few spots reaching upper 30s north of I-72 sunday night as high pressure settles into the area early next week. A pleasant stretch of dry fall weather expected from Monday through Thu night as high pressure stays nearby just southeast of central IL. Seasonably cool highs in the lower to middle 60s Monday to warm into the upper 60s to near 70F on Tue and low to mid 70s Wed/Thu. The Climate Prediction Center (CPC) 8-14 day outlook for Oct 20-26th continues 70% chance of above normal temperatures and 40% chance of above normal precipitation for CWA. So the growing season likely continues at least two more weeks over central and southeast IL. && .AVIATION...(For the 06Z TAFS through 06Z Friday night) Issued at 1147 PM CDT Thu Oct 12 2017 The extensive area of low cloudiness that was in place over central IL the past few days is rapidly dissipating as drier southerly flow pushes into the area. This may provide a brief period of VFR conditions after removing the MVFR cigs, however fog will likely form afterward, resulting in IFR-MVFR vsby. Think most of the fog will not be dense due to continuing light southerly winds. Fog should dissipate by 15Z, with scattered cloud cover lifting to around 5000 feet AGL by afternoon. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...37 SHORT TERM...07 LONG TERM...07 AVIATION...37