Christmas Mountain Village Snow Report

771 FXUS63 KILX 290750 AFDILX Area Forecast Discussion National Weather Service Lincoln IL 250 AM CDT Tue Sep 29 2026 .KEY MESSAGES... - Warm Midweek Temperatures: Highs will reach the low to mid-80s today and Wednesday, running 5 to 10 degrees above typical late-September averages. - Initial Rain Chances Wednesday: Rain chances increase late tonight into Wednesday, particularly near the Illinois River Valley, though confidence in widespread 1-inch totals remains low before Thursday. - Heavy Rain Potential Thursday to Friday: Widespread heavy rain is expected Thursday through Friday. Areas north of Interstate 70 have a 50 to 80 percent chance of exceeding 1 inch of rain, with a 40 to 60 percent chance of over 2 inches north of a Jacksonville to Rantoul line. - Cool and Dry Weekend: Drier, autumn-like conditions move in late Friday into Saturday, dropping weekend highs into the upper 60s and lows into the 40s. && .DISCUSSION... Issued at 247 AM CDT Tue Sep 29 2026 .Today through Wednesday... A rapid transformation in the synoptic pattern unfolds today across the Central CONUS as an expansive western trough absorbs the remnants of Tropical Depression Polo. Downstream shortwave energy ejecting out of the Plains into the Mid and Upper- Mississippi Valleys will flatten the amplified ridge overhead, simultaneously accelerating the departure of an East Coast upper low into the Atlantic basin. Associated return flow and robust thermal/moisture advection will send afternoon highs into the low to mid 80s both today and Wednesdaynearly 5 to 10 degrees above late-September climatology. Recent model guidance continues to display significant variability regarding the precise timing and magnitude of incoming precipitation, maintaining a fair degree of uncertainty along the heavy rainfall axis. However, notable trends in the 00z model suiteparticularly across the ECMWF and RRFS-MPAShave shifted the initial push of rain farther south for Wednesday. This reflects a distinct shift from yesterday`s global consensus, which maintained the predecessor rain event well to our northwest across Iowa and Wisconsin. In light of these trends, PoPs have been nudged upward from late tonight through midday Wednesday to capture the robust shortwave energy traversing the Illinois River Valley in tandem with forced WAA and isentropic lift. Forecast soundings illustrate that low-level saturation will occur gradually via top-down moistening. Consequently, confidence remains low regarding deterministic model depictions of widespread 1-inch rainfall totals prior to Thursday, owing to the predominantly non-convective nature of the rain and weak frontogenetical forcing during this early phase. Even so, an anomalously rich moisture plumewith PWATs exceeding the 99th percentile for late September (>1.75 inches)underscores the potential for highly efficient rainfall during this initial round should it fully materialize on Wednesday. .Thursday through Monday... The highest confidence for widespread, heavy rainfall remains centered in the Thursday through Friday timeframe. During this period, the main western shortwave opens up and tracks eastward along a slow-moving surface cold front. High confidence exists in widespread measurable QPF across Central and Eastern Illinois; however, exact storm-total accumulations will hinge heavily on the frontal speed and the sharpness of the baroclinic zone. Blended NBM guidance currently highlights a 50 to 80 percent probability of rainfall exceeding 1.0 inch north of Interstate 70 through Friday night. The potential for heavy rain exceeding 2.0 inches is highest (40 to 60 percent chance) north of a Jacksonville to Rantoul line, where localized mesoscale banding and training echoes could readily yield higher swaths. While low-end precipitation chances (15 to 25 percent) linger through midday Saturday to account for a potential delay in the northern stream shortwave, conditions will dry out rapidly from northwest to southeast as a broad Continental Polar (cP) high expands across the Midwest and Great Lakes. This airmass transformation will usher in a classic autumn cool-down relative to our midweek warmth, holding daily highs in the upper 60s and lows in the 40s to close out the week. Extended ensemble guidance suggests this expansive Canadian high will remain entrenched across the region through at least midweek, delivering a prolonged stretch of dry, ideal fall weather. && .AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/... Issued at 1151 PM CDT Mon Sep 28 2026 VFR conditions are expected to persist through the period. Surface winds will veer south Tuesday morning as high pressure departs. Incoming high clouds will gradually thicken and lower throughout the day ahead of an incoming frontal system. && .ILX WATCHES/WARNINGS/ADVISORIES... None. && $$ KEY MESSAGES...MJA DISCUSSION...MJA AVIATION...MJA