898 FXUS63 KILX 291147 AFDILX Area Forecast Discussion National Weather Service Lincoln IL 547 AM CST Tue Jan 29 2019 .SHORT TERM...(Today and tonight) ISSUED AT 325 AM CST Tue Jan 29 2019 Deep Arctic air on its way into the Northern Plains today, and expected to drop into the Midwest and bring dangerously cold temperatures to the region. The deep freeze is expected to continue through Thursday, peaking midweek, as wind chills drop into the -25F to -50F range for much of Central Illinois. High temperatures in the guidance today range from single digits to near 20F in the southeast. However, sustained winds increasing to 15-20 mph later this afternoon will mean that wind chills stay below zero all day, and less than -15F in the advisory today/roughly the northern half of IL. Models persist with a wave moving through the region today, and although they have been sparse with the QPF, a snow shower or two cannot be ruled out this afternoon and evening. May be confined to flurries, but at least worth a very low pop with scattered wording. Tonight, the temperatures drop even more significantly, with lows ranging from negative single digits in the southeast, and -20s from Peoria to Bloomington. Winds remain in the 15-20 mph range into the overnight due to an increasing pressure gradient with the deepening storm system over the Great Lakes. Those frigid temperatures with the sustained winds drop the wind chills into very dangerous territory ranging from the negative 20s and -30s across the southern half of the CWA...to the -45 to -50 range along and north of I-74. .LONG TERM...(Wednesday through Monday) ISSUED AT 325 AM CST Tue Jan 29 2019 The deep freeze continues and peaks tomorrow, with the coldest of the wind chills hitting in the early morning hours. Wednesdays high temperatures range from -12F in Galesburg to 5F in Lawrenceville. 850mb temps in the models have been very consistent with the core of the cold air centering over IL Wednesday morning. Models have also trended colder at 850mb a couple of degrees each run. In fact, this morning, temps of -35C to -37C are now over the NErn portions of ILX CWA. Slowly all of the models did, in fact, trend to the GFS that was an outlier only a few days ago. The cold continues Wed night into Thursday morning, but with slightly less wind. The headlines wind chill warning/advisory remain in place until mid morning/mid day on Thursday. Through the deep freeze, the forecast is mainly dry, but expect some blowing snow will remain possible particularly north of I-74 through this evening with the moderate winds. Beyond Thursday, the forecast warms with the western ridge expanding across the Plains and into the Mississippi River Valley, finally breaking the Midwest out of the broad synoptic trough and northwesterly flow. As expected in a northwesterly flow pattern aloft as that ridge expands, a series of small waves erupt in the noise of the pattern. The first of those is expected as a small quick clipper on Thursday, bringing a chance for some accumulating snow, in the afternoon and evening, with around an inch showing up in much of Central Illinois, but the details of this system are not solid just yet. Considering it will be part of a major pattern shift, expect the track to alter somewhat as well. Current extended forecast has temps rising to above freezing as the upper level ridge shifts east for the weekend...with a chance for more precip in the form of rain later in the weekend. && .AVIATION...(For the 12Z TAFS through 12Z Wednesday morning) Issued at 542 AM CST Tue Jan 29 2019 Mostly a gusty westerly wind forecast with a chance for light snow showers/flurries. Forecast cigs mid level clouds keeping it VFR throughout the forecast. One exception on sat imagery being a narrow swath of stratus at 2500 ft through the next couple hours possible at PIA. && .ILX WATCHES/WARNINGS/ADVISORIES... Wind Chill Advisory from midnight tonight to 9 AM CST Thursday for ILZ071>073. Wind Chill Warning from 9 PM this evening to noon CST Thursday for ILZ044>046-049>057-061>063-066>068. Wind Chill Warning from 6 PM this evening to noon CST Thursday for ILZ027>031-036>038-040>043-047-048. Wind Chill Advisory until 6 PM CST this evening for ILZ027>031- 036>038-040>043. && $$ SHORT TERM...HJS LONG TERM...HJS AVIATION...HJS