Challenge Mountain Snow Report

990 FXUS63 KAPX 180746 AFDAPX Area Forecast Discussion National Weather Service Gaylord MI 346 AM EDT Sat Jul 18 2026 .KEY MESSAGES... -Air quality improves this weekend with limited chances of precipitation. -Showers and thunderstorms return this Monday with stronger/severe potential. -Seasonably cool weather with mainly precipitation free conditions build beyond midweek next week. && .DISCUSSION... Issued at 344 AM EDT Sat Jul 18 2026 Pattern Synopsis: Longwave midlevel troughing continues to keep the majority of the CONUS occupied, while broad troughing currently centered over the Quebec/Newfoundland border influences the Northeastern U.S. An embedded wave will continue to dig across the Great Lakes Region this morning while moving downstream to the Lower Great Lakes this afternoon/evening, resulting in height rises across the CWA and generally improved weather. While a couple of low-level showers remain possible this morning, overall quiet weather is expected as surface high pressure builds combined with generally improving air quality. Another shortwave currently over the Pacific Northwest will progress eastward this weekend, developing surface low pressure lee of the Rockies and making its way to the Great Lakes Region this Monday. Southerly moisture advection this afternoon combined with increasing afternoon instability will likely lead to widespread showers and storms in the upper Midwest. Aforementioned longwave troughing will deepen beyond midweek next week leading to seasonably cold temperatures as we head into late July. Forecast Details: Today and Sunday: A few isolated showers remain possible this morning as last night`s wave continues to move downstream. Profiles remain dry in the mid and high levels but pockets of moisture could provide an additional trace or so before subsidence dries out the CWA and clears cloud cover this evening. The biggest noticeable change will be the improvement of Air Quality and integrated smoke values. An Air Quality Alert will continue through the daytime hours, but noticeable improvement will be a relief compared to Thursdays and Fridays conditions. Monday and Tuesday: The previously mentioned shortwave will return showers and storms to the CWA Monday afternoon/evening. Model soundings depict skinny CAPE profiles and enough instability to keep severe weather potential in the forecast. PWATs around the 75th percentile suggest heavy convective-driven rainfall for most areas while a few embedded discrete cells could generate hail. Widespread rainfall amounts will vary due to the nature of typical convective summertime rainfall, but highest probabilities of QPF remain between 0.50 and 1 at this time. Wednesday through Friday Outlook: Longwave midlevel troughing to the northeast will continue to influence the Great Lakes region through the remainder of the forecast period. Surface high pressure will keep conditions dry overall with a Canadian air influence delivering seasonably cool temperatures to the region. Highs will likely drop into the upper 60s/low 70s while our average across the CWA is generally 10-12 degrees warmer. && .AVIATION /06Z TAFS THROUGH 06Z SUNDAY/... Issued at 107 AM EDT Sat Jul 18 2026 Showers and storms still to bring some periods of MVFR to IFR cigs and vis restricting heavy rain yet early this morning, especially at KAPN. Rain threat ends quickly heading through the morning, leaving behind a fairly elevated cu field. Smoke will also dissipate substantially, with significant improvements in visibilities expected. Gusty northwest winds today become light tonight. && .APX WATCHES/WARNINGS/ADVISORIES... MI...Beach Hazards Statement from 8 AM EDT this morning through this evening for MIZ018. MARINE...Small Craft Advisory until 5 AM EDT Sunday for LHZ347-348. Small Craft Advisory until 5 AM EDT Sunday for LSZ321. && $$ DISCUSSION...SJC AVIATION...MSB