Hidden Valley Ski Area Snow Report

740 FXUS63 KLSX 290815 AFDLSX Area Forecast Discussion National Weather Service St Louis MO 315 AM CDT Sat Aug 29 2026 .KEY MESSAGES... - Abnormal heat is expected through the upcoming week, and there is a 30% chance for highs reaching 100 degrees through the week. && .SHORT TERM /THROUGH SUNDAY NIGHT/... Issued at 305 AM CDT Sat Aug 29 2026 Water vapor imagery shows upper-level ridging over the Great Plains, with a shortwave and associated convection moving into Minnesota and Iowa. Surface observations reveal that the area of high pressure at the surface responsible for our seasonable weather the last couple of days has moved well eastward of the CWA, with low-level flow becoming increasingly southerly. Through the day today, the ridge will build into the Midwest, pairing with the low-level southerly flow to bring warm air into the region. The aforementioned shortwave is expected to pass to the northeast of the CWA, and while the associated convection will not impact the CWA, cloud cover will. This cloud cover will be greatest over our Illinois counties. Given this cloud cover and warm air advection ramping up west to east, portions of central Missouri will see afternoon temperatures reach the low to mid 90s, while on the opposite side of the CWA across south-central Illinois, temperatures in the mid to upper 80s can be expected. Tomorrow, the upper-level ridge builds further into the Midwest; its axis being oriented roughly along the Mississippi River. This will allow the low-level thermal ridge to nose into the Middle Mississippi Valley, with 850 mb temperatures toping out in the low 20s degrees C. Mostly clear to partly sunny skies will allow for deep mixing, favoring afternoon temperatures in the mid to upper 90s for most locations. Despite these air temperatures, heat index values for most locations will stay beneath 100 degrees thanks to dew points in the low to mid 60s. && .LONG TERM /MONDAY THROUGH FRIDAY/... Issued at 305 AM CDT Sat Aug 29 2026 Confidence remains high that upper-level ridging will drive our local weather through the upcoming work week. Guidance consensus remains steady in that the axis of this ridge will be roughly centered along the Mississippi Valley, keeping an area of high pressure at the surface centered over the Southeast. The positioning of both of these features will keep deep south-southwesterly flow over the Middle Mississippi Valley from Monday through at least Friday. During that time, 850mb temperatures will hover in the low to mid 20s degrees C, climatologically favoring surface temperatures in the mid to upper 90s degrees F. Confidence in this heat is high given the aforementioned continued consensus among guidance and that surface flow will at times be southwesterly. This flow will allow for adiabatic warming off of the Ozark Plateau, providing a boost to temperatures and a drop in dew points particularly for locations across central and southeastern Missouri. Highs reaching 100 degrees can`t be ruled out, with the NBM continuing to have roughly a 30% chance of this happening - particularly within the St. Louis metro area. Highs of this magnitude will come close to records, with overnight lows having even a greater potential for breaking max low records. Please see the Climate section for more details. Even with this degree of heat, confidence remains low in the need for heat headlines. The most likely scenario is that at least portions of the area see a Heat Advisory thanks to 4 or more days of 100+ degree heat index values. While there are many locations that currently reach those criteria in our current forecast, this hinges on dew points not trending any lower than they currently are. The NBM and many guidance sources typically do not handle local temperatures and dew points well on days with southwesterly surface flow in place. Given this and that bias-corrected guidance is being influenced by the higher humidity we`ve experienced the last couple of months, it may not be until we experience a day or two of this pattern before we are able to confidently say how humid the air mass will be the rest of the week. && .AVIATION /00Z TAFS THROUGH 06Z SUNDAY/... Issued at 1130 PM CDT Fri Aug 28 2026 Cool temperatures through the pre-dawn hours and light to calm winds will lead to another round of steam fog along local waterways. River valley sites KJEF, KSUS, and KCPS have the greatest chance of seeing impacts from this fog. Once any fog that develops this morning dissipates shortly after sunrise, confidence is high in dry and VFR flight conditions at all local terminals through the day. && .CLIMATE... Issued at 305 AM CDT Sat Aug 29 2026 Record Highs...Record High Lows (value/year): August 31 KSTL: 103/2013...79/2013 KCOU: 103/1913...78/1947 KUIN: 100/2011...76/1924 September 1 KSTL: 104/2011...82/2011 KCOU: 102/1913...76/1913 KUIN: 104/2011...78/2011 September 2 KSTL: 101/2011...80/2011 KCOU: 100/1913...77/1913 KUIN: 103/1913...80/1913 September 3 KSTL: 101/2011...80/1913 KCOU: 103/1939...75/1939 KUIN: 103/1913...78/1913 && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ SHORT TERM...Elmore LONG TERM...Elmore AVIATION...Elmore CLIMATE...Elmore