Indianhead Mountain Resort snow report

020 FXUS63 KILX 040806 AFDILX Area Forecast Discussion National Weather Service Lincoln IL 306 AM CDT Sat Jul 4 2026 .KEY MESSAGES... - Dangerous heat and humidity will continue this afternoon, particularly near and south of Interstate 70 where there is a 40% to 60% chance that temperatures will exceed 90F. Heat index values in this southern corridor are expected to peak between 100F and 105F. - Widespread thunderstorms are expected to develop this afternoon and evening across central Illinois (60-80% chance). While organized severe weather is unlikely, any storm could produce localized torrential rainfall leading to minor flooding, as well as isolated damaging wind gusts. - A refreshing break from the heat arrives early next week. Following a final round of scattered showers on Sunday, a cold front will bring a stretch of dry and comfortable weather with highs in the mid-80s from Monday through Wednesday. && .DISCUSSION... Issued at 253 AM CDT Sat Jul 4 2026 ...Heat and Humidity... Central Illinois starts this morning noticeably cooler and more stable than previous days, courtesy of widespread nocturnal convection. The primary forecasting challenge revolves around how efficiently the boundary layer can mix out this stable airmass. Given the high July sun angle, any brief windows of clearing by early afternoon will promote rapid boundary layer recovery. The latest HREF guidance points to the highest probability (40-60% chance) of temperatures exceeding 90F near and south of the Interstate 70 corridor. This aligns well with recent observational trends; infrared satellite and radar imagery show convective outflows stalling out in the vicinity of I-70. Consequently, this corridor represents the greatest risk for advisory-level heat index values ranging from 100F to 105F this afternoon. While heat index values of 95F to 100F may be more common north of I-70, the current Heat Advisory will be maintained in full to account for the possibility of a more aggressive midday recovery. ...Severe and Heavy Rainfall Potential... Confidence in widespread afternoon convection has risen based on overnight upstream trends. Multiple Mesoscale Convective Systems (MCSs) will continue tracking eastward this morning within a chaotic, zonal flow regime, gradually decaying with eastward extent. By early afternoon, multiple Mesoscale Convective Vortices (MCVs) embedded within a convectively- augmented shortwave will cross the Mid-Mississippi Valley, providing the necessary synoptic ascent to ignite widespread thunderstorm activity across central Illinois. As the boundary layer recovers today, temperatures climbing into the mid-to-upper 80s alongside rich dewpoints in the low- to-mid 70s will yield 2,5003,000 J/kg of MLCAPE. While the thermodynamic parameter space is robust, it will once again be undercut by weak kinematic profiles, featuring deep-layer bulk shear generally at or below 20 knots. However, the approaching shortwave could locally enhance deep-layer shear up toward 30 knots. Widespread, organized severe weather is not anticipated. Instead, within a high-PWAT, tropical airmass, high precipitation efficiency will favor pulse convection or transient, disorganized clusters. The primary hazards with this activity will be localized torrential downpours and wet microbursts capable of isolated wind damage. Convective activity is expected to taper off from west to east by mid-to-late evening as subsidence builds in behind the departing MCVs and shortwave. Given the absence of a strengthening low-level jet (LLJ), storms should struggle to fester past 9:00 PM to 10:00 PM. ...Next Week... By midday Sunday, the primary upper-level shortwave trough axis will begin crossing the region, dragging an attendant surface cold front through central Illinois. Because airmass recovery occurs readily this time of year, boundary layer conditions ahead of the front appear favorable enough to support another round of scattered thunderstorms on Sunday afternoon. The passage of this cold front will effectively scour out the multi-day tropical airmass. Dewpoints are forecast to drop back into the much more comfortable mid-60s to lower 70s by Monday. A welcome stretch of seasonable and dry weather is anticipated from Monday through Wednesday as a transient shortwave ridge builds across the Midwest. Expect daytime highs to hover comfortably in the mid-80s during this period. The midweek respite looks to be short-lived. Long-range guidance hints at a return to unsettled weather by late next week as a well- defined trough is projected to dig across the Upper Midwest. This system will drag another cold front into the region, which is modeled to stall somewhere over the state. This setup will reintroduce daily chances for showers and thunderstorms heading into the weekend. && .AVIATION /06Z TAFS THROUGH 06Z SUNDAY/... Issued at 1209 AM CDT Sat Jul 4 2026 Showers and thunderstorms are ongoing across central Illinois and are expected to continue overnight, though we should gradually see a diminishing trend in coverage. Storms are expected to redevelop over the region by Saturday afternoon and evening, though confidence in specifics (timing/location) is low at this time. Wind fields will be disrupted by convection in the region, thus expect quite a bit of variability in wind direction, though wind speed should generally stay under 10 kt outside of storms. && .ILX WATCHES/WARNINGS/ADVISORIES... Heat Advisory until 7 PM CDT this evening for ILZ029-031- 036>038-040>057-061>063-066>068-071>073. && $$ KEY MESSAGES...MJA DISCUSSION...MJA AVIATION...Deubelbeiss