The Mountain Top At Grand Geneva Resort Snow Report

597 FXUS63 KLOT 200724 AFDLOT Area Forecast Discussion National Weather Service Chicago/Romeoville, IL 224 AM CDT Sun Sep 20 2026 .KEY MESSAGES... - A Flood Watch for flash flooding has been extended through early this afternoon for areas roughly along and north of the Illinois and Kankakee rivers. - Periods of showers and thunderstorms with torrential rain and localized flash flooding are expected through midday today. - Below normal temps through the end of the week. && .DISCUSSION... Issued at 224 AM CDT Sun Sep 20 2026 The flood watch has been extended until 18z today. Periods of showers and thunderstorms are expected to continue through at least mid morning for much of the watch area. The main surface low won`t reach central IN until this afternoon and this may keep persistent moderate/heavy rains across parts of the area through midday. And even from this short(er) distance, there is still some uncertainty where the heaviest rains may fall. The current activity may favor the I-80 corridor in the next few hours and the next wave over eastern IA may favor areas along and north of I-80 with perhaps later waves this morning favoring areas south of I-80. With all this in mind, opted to extend the flood watch through 18z and as trends emerge, the watch can be cancelled as needed later this morning. As for rainfall amounts, there could be one or two swaths of 3-5 inches of rain by the time it ends later today, which could lead to flash flooding. Showers and scattered thunderstorms may still be moving across the southeast cwa later this afternoon into early this evening before precipitation finally comes to an end. There may be lingering showers tonight and perhaps a few showers on Monday, but only isolated coverage expected. Fog developed over southern Lake Michigan Saturday evening and briefly moved onshore along the IL shore. Webcams suggest the visibilities have improved right near Lake Michigan and as northerly winds slowly increase through the morning, this fog may lift into a low cloud ceiling. Fog over Lake Michigan is also expected to slowly lift as well, though perhaps not until the winds increase further later this morning. Strong northeast winds will develop today and remain strong through Wednesday producing high waves and dangerous swimming conditions at Lake Michigan beaches. Still quite a bit of uncertainty for a possible upper low and shower chances this week. Temperatures look to be well below normal for the end of September with high temps mainly in the 60s through Thursday. cms && .AVIATION /06Z TAFS THROUGH 12Z MONDAY/... Issued at 103 AM CDT Sun Sep 20 2026 Key aviation forecast messages: - Period of TSRA across the region through daybreak. Additional SHRA linger through midday/early afternoon. - IFR CIGs/VIS likely into midday before gradually improving, with a period of at least intermittent LIFR possible through the predawn hours this morning. - Northeast winds gradually increase toward/just after daybreak and become gusty in the 20-25 kt range especially from midday into tonight. A series of mid-level disturbances will track across the region through this afternoon, providing moist ascent for heavy convective SHRA/TSRA north of a stationary frontal zone across northern IL/IN. TSRA threat looks to focus in the I-88/I-80 corridors through about daybreak with MDW/GYY most likely to have direct impacts, though at least scattered TS may get as far as RFD and C90 Chicago TRACON airspace will be affected. Thunder threat appears to shift south of the terminals beyond daybreak, though convective SHRA will persist (possibly with areas of drizzle as well) while gradually become more scattered this afternoon. With several rounds of showers low-levels have become fairly saturated, resulting in areas of LIFR CIGs at issuance time especially from RFD/ORD north and northeast at issuance time. Model guidance continues to hit IFR (CIGs and VIS) pretty hard through midday/early afternoon, with LIFR CIGs during the predawn hours (though may be patchy as SHRA/TS mix things up a bit). Improvement to MVFR may not occur until later this afternoon or even toward evening. Light east/variable winds will turn northeast predawn as a weak surface low pressure wave passes south of the terminals. Winds will begin to strengthen around/after daybreak as the gradient tightens in response to high pressure building across Ontario and the northern Great Lakes. Gusts of 20-25 kts likely by afternoon, with a few higher gusts possible especially later this afternoon and evening. Ratzer && .LOT WATCHES/WARNINGS/ADVISORIES... IL...Flood Watch until 1 PM CDT this afternoon for ILZ003-ILZ004- ILZ005-ILZ006-ILZ008-ILZ010-ILZ011-ILZ012-ILZ013-ILZ019- ILZ020-ILZ021-ILZ023-ILZ103-ILZ104-ILZ105-ILZ106-ILZ107- ILZ108. Beach Hazards Statement from 7 AM CDT this morning through Tuesday evening for ILZ006-ILZ103-ILZ104. IN...Flood Watch until 1 PM CDT this afternoon for INZ001-INZ002. Beach Hazards Statement from 10 AM CDT this morning through Tuesday evening for INZ001. Beach Hazards Statement from 10 AM CDT this morning through Monday morning for INZ002. LM...Dense Fog Advisory until 9 AM CDT this morning for the IL and IN nearshore waters. Small Craft Advisory from 7 AM this morning to 7 PM CDT Tuesday for the IL nearshore waters. Small Craft Advisory from 10 AM this morning to 7 PM CDT Tuesday for Calumet Harbor IL to Burns Harbor IN. Small Craft Advisory from 1 PM this afternoon to 7 AM CDT Monday for Burns Harbor to Michigan City IN. && $$ Visit us at weather.gov/chicago