FXUS63 KLOT 111119 AFDLOT Area Forecast Discussion National Weather Service Chicago/Romeoville, IL 519 AM CST Mon Dec 11 2023 .SHORT TERM... Issued at 235 AM CST Mon Dec 11 2023 Through Tuesday night... Key Message * Stratus clears out from the west and southwest today Seasonably symbolic stubborn stratus sticking around this morning, though gradual clearing is expected today as low level flow backs and becomes anticyclonic. With stratus probably lingering into the early afternoon hours over the eastern CWA, did trim a couple degrees off of forecast highs today, but still in the ballpark of seasonal norms. A south to southwesterly breeze will lock in tonight as the pressure gradient tightens a bit in advance of a cold front trailing south from a low over Canada. Despite mostly clear skies tonight, the south winds should temper the temperature fall a bit with lows mostly in the mid-upper 20s. Cold front will move across the area Tuesday morning with very little fanfare, just a wind shift to the west-northwest. Brunt of the cold air should stay north of our CWA, so shouldn't see much of a temp drop with the front. Temps Tuesday night will be a bit tricky. Assuming the encroaching mid-high level cloudiness doesn't put too big of a kibosh on temp fall, then the light/variable winds and ambient cold air mass would support lows in the teens across interior northern IL away from the Chicago metro urban heat island. Assuming those low temps verify, this will probably end up being the coldest night over the next 7-10+ days. - Izzi && .LONG TERM... Issued at 235 AM CST Mon Dec 11 2023 Wednesday through Sunday... Key Message * Return to warmer than average temps later this week through next weekend with minimal chances of precipitation Wednesday will be one last cold (temps near average) day before mild Pacific air mass floods east across the country. Still seeing hints of potentially some small scale northern stream disturbance impacting the region this weekend, but guidance continues to vary from run to run and NBM pops are below mentionable, which is fine for now. Thursday through Sunday highs look to be in the 40s, with 50F not out of the question. - Izzi && .AVIATION... For the 12Z TAFs... Long duration MVFR stratus is expected to persist through early afternoon then gradually clear out from west to east. Winds will be light W to SW today then turning SSW to S after sunset. A cold front moves through early Tuesday morning turning winds NW with increasing gustiness to near 20kt. Petr && .LOT WATCHES/WARNINGS/ADVISORIES... IL...None. IN...None. LM...None. && $$ Visit us at weather.gov/chicago Follow us on Facebook, Twitter, and YouTube at: www.facebook.com/NWSChicago www.twitter.com/NWSChicago www.youtube.com/NWSChicago