Area Forecast Discussion
Issued by NWS Central Illinois
Issued by NWS Central Illinois
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982 FXUS63 KILX 092033 AFDILX Area Forecast Discussion National Weather Service Lincoln IL 233 PM CST Sun Nov 9 2025 .KEY MESSAGES... - Cold and breezy conditions stick around through Monday night. Wind chill values Monday morning will dip down into the upper single digits to teens. - Scattered snow showers redevelop this evening, potentially resulting in minor snow accumulations, brief reductions in visibility, and some slippery spots on roads. - A lake-effect snow band is forecast to bring accumulating snow to east-central Illinois tonight. There is a 20-40% chance for over 2 inches of snow in parts of Champaign and Vermilion counties. && .DISCUSSION... Issued at 233 PM CST Sun Nov 9 2025 Upper air analysis shows deep troughing over the eastern half of the CONUS with a surface low positioned over Pennsylvania. Cold, breezy, and downright raw conditions are being observed over central Illinois this afternoon with temperatures sitting in the low to middle 30s and wind chills in the 20s. Light snow showers continue this afternoon, though should generally wane to mainly flurries over the next few hours. Regional radar mosaic shows a band of lake- effect snow stretching from eastern Lake Michigan into north-central Indiana, with some enhancement from this over Vermilion/Edgar counties as of 2 pm. Overnight lows will be a solid 10-15 degrees cooler than normal with values dipping down into the low to mid 20s. Breezy winds overnight will send wind chills into the upper single digits to teens. Precipitation chances will increase heading into the evening/overnight hours as a lobe of vorticity dives south through the area, steepening low to mid-level lapse rates to around 7-9 C/km. High resolution models show snow shower activity entering west- central Illinois around 00Z/6 pm then sliding into southeast Illinois around 06Z/midnight. Although models suggest the snow showers will be more cellular in nature, conditions for squall-like activity are above par with the SNSQ parameter >1 and SBCAPE between 15-45 J/kg. However, low-level frontogenesis doesn`t look particulary impressive, which should limit the threat for linear squall development. Despite this, expect brief reductions in visibility (below 1 mile at times) and light snow accumulations with any robust showers tonight. Lake-effect snow ramps up overnight as winds turn north- northeasterly over Lake Michigan. Models show the lake enhanced showers stretching as far west as the I-57 corridor overnight into Monday morning, with a more localized band nosing into parts of Champaign and Vermilion counties. Things look quite impressive for heavy accumulating snow north and northeast of here, though recent guidance continues to show the potential for higher amounts to nose into our area. The 09.12Z HREF shows mean snow accumulations over Champaign and Vermilion counties upwards of 1-2 inches, though worst case scenario forecasts have a small area in northern parts of the counties exceeding 3-4 inches. As of now, there is about a 20-40% chance that these areas see over 2 inches of snow. This will result in reduced visibility in snow showers and some slippery spots on roads where snow sticks. Cold and breezy weather remains through Monday, with daytime highs in the low to middle 30s. The upper trough will lift northeast by Tuesday as surface high pressure slides off to our south. Southerly return flow will send milder weather back northward, with well above normal temperatures expected to arrive by the end of the week. In fact, the NBM shows highs by Saturday in the upper 60s to low 70s. Upper ridging will keep things mostly dry this week, with early indications for a strong system to bring beneficial rain next weekend. NMA && .AVIATION... (For the 18z TAFs through 18z Monday Afternoon) Issued at 1141 AM CST Sun Nov 9 2025 A handful of disturbances rotating about an expansive upper level low pressure system will give periodic opportunities for snow showers through tonight, resulting in fluctuating flight conditions. Surface heating should lift cloud bases but also maintain broken ceilings around FL030 to FL040 through the afternoon. Within snow showers, ceilings and especially visibilities may drop sharply. CAMs generally suggest a lull in snow shower activity between 20-24z, with another batch arriving from the north and potentially impacting the terminals between roughly 01-08z. Then, there is potential for a lake effect snowband to bring more persistent snow and attendant visibility reductions to CMI, and potentially (30% chance) BMI and DEC after roughly 08-09z. In addition to snow, a mesoscale low developing with that band may also bring another uptick in winds, with gusts to 30+ kt again for several hours Monday morning. Otherwise, expect northwest gusts to 30 kt early to mid afternoon today, easing to 20-25 kt this evening. Bumgardner && .ILX WATCHES/WARNINGS/ADVISORIES... None. && $$