582 FXUS63 KILX 132016 AFDILX Area Forecast Discussion National Weather Service Lincoln IL 216 PM CST Tue Dec 13 2022 .SYNOPSIS... Issued at 216 PM CST Tue Dec 13 2022 Mild weather is expected through midweek with high temperatures peaking into the 50s on Wednesday. Periods of rain will continue tonight through Wednesday night across the area. Southeast winds with gusts up to 35-40 mph develop going into this evening. Cooler weather filters back in for the end of the week, with snow showers possible mainly north of I-74 Thursday night into Friday. && .SHORT TERM...(This evening through Wednesday night) ISSUED AT 216 PM CST Tue Dec 13 2022 Water vapor imagery depicts a large trough over the western US with a defined comma head over the central Plains states where the low is occluding. Further east, a large swath of precipitation is working east into the Midwest states. Dry air in the low to mid levels of the forecast area has prevented rain from reaching the ground some areas, but the column is starting to saturate with rain now being observed as far east at the I-55 corridor and vicinity. The aforementioned low will lift northeast into the Upper Mississippi River Valley by this evening, with the occluded front pushing most of the precipitation east of here late tonight into Wednesday morning. Rainfall totals through Wednesday morning look to range from 0.75 to 1 inch, with the highest over western parts of the forecast area. Although the better moisture and instability with this system look to remain outside of the forecast area, a few thunderstorms will be possible due to the strong dynamical forcing of the system. In fact, a few lightning strikes have been noted late this morning-early afternoon over eastern Missouri under the left exit region of a 110+ kt upper jet. As the low lifts northward today, southeast winds will ramp up later this afternoon into evening as rapid pressure falls overspread the area. Wind gusts between 35-40 mph will be possible, with occasional gusts up to 45 mph west of I-57 through about midnight. The HREF continues to suggest gusts over 45 mph during a short window this evening, though forecast soundings argue the inversion will keep gusts below 45 mph. Upstream observations over Iowa have generally been in the 30-40 mph range, reassuring that the inversion is too strong to mix down any higher gusts. Because of this, a Wind Advisory will not be issued. A brief lull in the precipitation will occur Wednesday morning as the dry slot works into the area before another slug of moisture lifts northward ahead of a surface cold front. Temperatures will be the warmest of the week and possibly the last mild day of the year with highs expected to top out in the 50s. Short term guidance shows another slug of rain showers entering the area later Wednesday morning and continuing into the evening hours, with the focus being over eastern parts of the state. Additional rain amounts of around 0.50" are expected mainly east of I-57 with lesser amounts west of there. When all said and done, rain totals through Wednesday night look to top out near 1-1.25", though some locally higher pockets will be possible mainly in eastern Illinois. With ongoing abnormally dry to moderate drought conditions across the state, this rainfall will be very beneficial. The cold front start to work through the area Wednesday night with cooler temperatures filtering back in. && .LONG TERM...(Thursday through Tuesday) ISSUED AT 216 PM CST Tue Dec 13 2022 The occluded surface low will be slow to exit the Upper Mississippi Valley Region later this week, but an upper ridge over the western CONUS will come to the rescue and kick it east of the Great Lakes Region by later this weekend. Post frontal temperatures will be seasonable on Thursday before a reinforcing surge of cold air brings colder temperatures for Friday onward. Some wrap around moisture and lobes of vorticity will bring low end chances for light rain/snow mix mainly to areas north of I-74 later Thursday and on Friday. Little to no accumulation is expected with these at this time. Cooler air sticks around through the weekend with high temperatures in the upper 20s to 30s and overnight lows in the upper teens to 20s, which isn't too far below normal for this time of the year. We look to stay mostly dry through the weekend, though cloud cover may be hard to break out of with the upper low's slow denature. Some sunshine should *hopefully* make a return by Sunday as a surface high brushes the area. There remain large differences in forecast solutions by the middle of next week and beyond. However, it appears that much colder weather is favored. The CPC's 6-10 day and 8-14 day outlooks suggest well below normal temperatures through next weekend, including over the Christmas holiday. Because of this, any precipitation that falls during this time would likely be in the form of snow. So those that are craving a white Christmas, the odds may be turning in your favor. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) Issued at 1127 AM CST Tue Dec 13 2022 Overcast VFR skies and east-southeasterly winds are in place area- wide to start the period. MVFR ceilings move in from the southwest this afternoon, along with rain. Winds become breezy, with gusts of 25-30 knots beginning late this afternoon and continuing through much of the overnight. Ceilings continue to lower tonight, with IFR ceilings likely, and guidance shows a chance of LIFR ceilings after 09z. Visbys will be variable due to the precip, but MVFR visbys are expected to be most prevalent beneath the rain. Rain will exit to the northeast during the morning on Wednesday, but little ceiling improvement is expected through the end of the period. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...NMA SHORT TERM...NMA LONG TERM...NMA AVIATION...Erwin