Hidden Valley Ski Area Snow Report

558 FXUS63 KLSX 040448 AFDLSX Area Forecast Discussion National Weather Service St Louis MO 1148 PM CDT Thu Sep 3 2026 .KEY MESSAGES... - A late summer heat wave will continue areawide through Saturday. - Temperatures are forecast to "cool" slightly Sunday into Labor Day before another period of near-record breaking heat returns by Wednesday. && .SHORT TERM /THROUGH SATURDAY/... Issued at 236 PM CDT Thu Sep 3 2026 Surface temperatures and heat index values are nearly identical to yesterday`s values as of 1900 UTC, though maybe a degree or so lower in many locations. Diurnal cumulus though has developed ~1 hour earlier and more to the northeast compared to yesterday, so these clouds may have a slight (1-2F at most) impact across southeast and east-central Missouri as well as southwest Illinois. That being said, most areas will still see peak heat index values in the 100-105F range, with some spots of 105F+. Speaking of the cumulus field, a few brief rain showers are possible, but the vast majority of the area will stay completely dry. The coverage of any shower activity looks to be too low to mention explicitly via a slight chance (15+%) PoP. Persistence, persistence, persistence remains the rule through Saturday. Any change to the ambient air mass is negligible, at best. Lows each night are forecast to be in the 70s, with the exception of near 80 degree minimums within the urban heat island of metropolitan St. Louis. Highs both Friday and Saturday are expected to be in the mid to upper 90s, with a few locations topping out near the century mark. Peak heat index values of 100-105+F are expected as well near or just after midday before some mixing out of dewpoints occurs. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... Issued at 236 PM CDT Thu Sep 3 2026 (Saturday Night - Labor Day) Subtle changes have been noted for the latter part of the Labor Day holiday weekend forecast. Notably, the surface high pressure across the Great Lakes has trended a bit stronger on ensemble guidance, helping to push the backdoor cold front more to the west. It appears more likely that much of (if not all) the area should see some low- level cold air advection behind this front as winds turn out of the east/northeast. Now high temperatures will not exactly be "cool" by any means, but should drop on average a few degrees each day from Saturday through Labor Day. Highs more in the low to mid 90s are forecast. Dewpoint (relative humidity) values are always harder to forecast, but there is a pretty strong signal for a fairly significant push of dry air to advect in from the Great Lakes. Probabilities for dewpoints to be below 65 degrees Labor Day afternoon are above 60% areawide, with along/east of the Mississippi River even having pretty good chances for sub 60 degree values (over 40%). So, not only are temperatures cooling, but lower humidity is also likely to move into the region by Labor Day. If this holds true, we may at least get a brief break from heat index values near 100 degrees across the entire area for Labor Day, and many locations beginning Sunday behind the backdoor front. (Tuesday - Next Thursday) There remains high confidence in a return to near-record breaking temperatures by Wednesday as mid/upper level ridging moves back over the mid-Mississippi Valley. The strength of the 500-hPa level ridge is likely to be record breaking for early September. In addition, the 850-hPa thermal ridge is also expected to bisect the CWA, with temperatures at that level well above +20C (>99th percentile). This is also 6 days out, with mostly hot and dry conditions so soils should continue to dry out. In theory, that may yield our hottest temperatures of the entire stretch. The latest NBM has widespread upper 90s with some locations around the century mark, which looks pretty representative. If anything, it may end up a touch warmer than currently forecast. Uncertainty increases sharply Wednesday night into next Thursday due to the possibility of a cold frontal passage. Two of the four clusters of the 500-hPa height pattern from the LREF (37% of members) show the anomalous ridging holding strong while the other two clusters (63% of members) show more zonal flow with a stronger trough as well crossing the Great Lakes. The former pattern would mean a continuation of near-record breaking heat while the later would send the cold front through the area and bring much cooler (closer to normal) temperatures. The inter-quartile range of the NBM shows this spread well, with about 10-15 degrees between the 25th/75th percentiles, and nearly 15-25 degrees from the 10th to the 90th percentile. && .AVIATION /00Z TAFS THROUGH 06Z SATURDAY/... Issued at 1147 PM CDT Thu Sep 3 2026 Dry and VFR flight conditions will persist through the TAF period with light winds, mainly southwesterly during the day Friday. && .CLIMATE... Issued at 1220 PM CDT Wed Sep 02 2026 Record Highs...Record High Lows (value/year): September 3 KSTL: 101/2011...80/1913 KCOU: 103/1939...75/1939 KUIN: 103/1913...78/1913 September 4 KSTL: 104/1954...81/1925 KCOU: 103/1913...73/1947 KUIN: 105/1913...75/1947 September 5 KSTL: 103/1954...80/1899 KCOU: 103/1899...75/1983 KUIN: 100/1925...76/1912 && .LSX WATCHES/WARNINGS/ADVISORIES... MO...Extreme Heat Warning until 8 PM CDT Saturday for MOZ018-019- 026-027-034>036-041-042-047>052-059>065-072>075-084-085- 099. IL...Extreme Heat Warning until 8 PM CDT Saturday for ILZ058>060- 064-065-069-070-074-079-095>102. && $$ SHORT TERM...Gosselin LONG TERM...Gosselin AVIATION...Pfahler CLIMATE...Britt