Indianhead Mountain Resort Snow Report

015 FXUS63 KILX 250807 AFDILX Area Forecast Discussion National Weather Service Lincoln IL 307 AM CDT Sat Jul 25 2026 .KEY MESSAGES... - Morning showers and isolated thunder will taper off by midday, leaving behind widespread low clouds and a sharp temperature gradient this afternoon (70s east, mid 80s west). - Oppressive heat and humidity arrive Sunday and Monday with heat index values climbing to 100-110F. Existing Heat Advisories will likely be expanded and upgraded for Monday should current forecast trends hold. - Severe weather probabilities increase Sunday into Monday along the periphery of the ridge (Ring of Fire / Northwest flow setup), with Monday presenting the most favorable convective window ahead of an approaching cold front. && .DISCUSSION... Issued at 300 AM CDT Sat Jul 25 2026 .Today through Tonight... A warm front stretching from eastern South Dakota down into the Missouri Ozarks continues to drive robust warm-air advection (WAA) and isentropic lifting across our forecast area. Expect scattered light rain showers and perhaps an isolated embedded thunderstorm to track across the region this morning, primarily focused along and south of the I-72 corridor. By midday, an incoming elevated mixed layer (EML) will rapidly strip mid-level column moisture, shutting off precipitation from northwest to southeast. However, low-level moisture won`t clear as quickly; persistent 850 mb WAA overrunning the cool side of the surface boundary will keep a blanket of stratus locked in place into the late afternoon and evening, especially across eastern Illinois. To account for this, high temperatures have been nudged down a bit. This sets up a stark east-to-west temperature gradient across central Illinois today: upper 70s where clouds remain locked in (east), ranging to mid 80s where partial clearing occurs (west). Overnight, stratus will re-expand and lower as the surface warm front approaches and moisture gets trapped beneath a sharp, low- level inversion. Cloud cover and elevated boundary-layer moisture will severely limit diurnal cooling, keeping overnight lows muggy in the lower 70s. .Sunday through Monday Night (Extreme Heat & Severe Potential)... The mid-level ridge axis crosses directly overhead Sunday and Monday, bringing the most oppressive heat wave of the summer so far. Ensemble guidance (GEFS/ECE/CMC) exhibits remarkable clustering, bringing top-tier 850 mb temperatures (23-25C) directly into the Midwest. Afternoon highs will easily reach the lower-to-mid 90s both days. When coupled with rich Gulf moisture driving surface dewpoints into the upper 70s to near 80F, heat index values will soar into the 100-110F range both afternoons. A Heat Advisory remains in effect for counties east of I-57 on Sunday. Given medium-high confidence in peak heat index values between 105-110F across the entire forecast area on Monday, headlines will almost certainly be upgraded and expanded in upcoming forecast packages. Beyond the heat concerns, a representative "Ring of Fire" convective environment is anticipated along the northern flank of the established ridge. Although robust thermodynamic profiles will materialize, with SBCAPE values likely surpassing 4000 J/kg, subsidence/capping should suppress most development through Sunday daylight hours. The window for higher-impact convection opens Monday afternoon as a duo of shortwave impulses crest the ridge and propel a surface cold front toward the area. While forecast confidence regarding exact convective evolution remains low, any organized clusters (MCS) that successfully breach the cap will encounter an environment conducive to significant damaging winds, large hail, and localized flash flooding. .Tuesday through Friday... The cold front is modeled to push slowly south across central Illinois on Tuesday. This will begin the process of flushing out the oppressive airmass, though lingering heat and high humidity (dewpoints holding in the 70s) will hang on across southeast Illinois through Tuesday afternoon. Highs Tuesday will top out in the upper 80s to near 90F. From Wednesday through the end of the week, central Illinois shifts into classic summer northwest flow on the eastern flank of the amplified central US ridge. While extreme thermodynamic profiles ease off, northwest-flow regimes in late July notoriously foster upstream convective complexes tracking toward the region. Expect temperatures and humidity to return to near seasonal norms (highs in the upper 80s, heat indices mid 90s) with periodic, episodic storm chances. && .AVIATION /06Z TAFS THROUGH 06Z SUNDAY/... Issued at 1208 AM CDT Sat Jul 25 2026 Ceilings continue to steadily lower, and by 12-14z, MVFR conditions will prevail. NBM probabilities of ceilings below 1,000 feet are around 20-25% through the morning at most of the terminals, though ceilings should lift enough before they reach as far east as KCMI. Gradual improvement from west to east is expected in the afternoon, though it may take until about 00z before VFR conditions return to KCMI. Scattered showers will continue into mid morning, mainly from about KSPI-KCMI south. Thunder chances are fairly low and will not be included in the new TAF set, but if any were to occur, they would be closer to 12-15z. && .ILX WATCHES/WARNINGS/ADVISORIES... Heat Advisory from noon Sunday to 9 PM CDT Monday for ILZ027>031-036>038-040>044-047>054-061. && $$ KEY MESSAGES...MJA DISCUSSION...MJA AVIATION...Geelhart