Four Lakes Village snow report

607 FXUS63 KLOT 180600 AFDLOT Area Forecast Discussion National Weather Service Chicago/Romeoville, IL 100 AM CDT Mon May 18 2026 .KEY MESSAGES... - Additional rounds of showers and thunderstorms Monday through Tuesday, some of which could be severe at times. - Summer-like warmth and breezy winds at times will prevail through Tuesday before cooler temperatures return for the middle of the week. && .DISCUSSION... Issued at 130 PM CDT Sun May 17 2026 A robust convectively-augmented MCV continues to pivot north out of southern Wisconsin and away from our region early this afternoon. Modest large scale height rises will develop over the local region which will promote precip-free conditions across the area the rest of the afternoon. The one exception might be across our far northwest where some lingering glancing ascent co-located with cooler mid-level temperatures may support some lingering spotty sprinkles. In advance of our next weather-maker, tonight will feature warm and somewhat humid conditions. With a tightening surface pressure gradient and only modest decoupling, should see at least intermittent gusty southerly breezes through the night. Expansive strong to severe convection is expected to develop later this afternoon and evening across the central and northern Great Plains along an eastward-advancing cold front. Given the strong nature of low-level forcing with the front, it`s not surprising that there`s good model agreement suggesting upscale growth into one or two expansive MCSs through the evening hours. While some timing discrepancies remain, there`s a general consensus for this activity to approach our forecast area just prior to daybreak Monday morning. Deep layer shear over the local area is not forecast to be particularly robust, and generally oriented from southwest to northeast, roughly parallel to the progged MCS(s). This overall is not favorable-- combined with the time of day and nocturnally-stabilized boundary layer--for robust convective sustenance. At this time, it appears the most probable scenario is for a decaying thunderstorm complex, potentially with lingering strong gusty outflow and maybe some cores with a small hail potential, to push into the region through Monday morning. In this scenario, expansive cloud cover, trailing stratiform rain, and some embedded thunderstorms may linger well into Monday afternoon across the northwest half of the CWA (roughly NW of I-55). This would obviously significantly reduce the subsequent afternoon severe weather threat across this area. If this morning complex doesn`t just surge through the entire forecast region (which remains a potential), muted insolation, with the bulk of the anvil blow off likely streaming northeast as opposed to easterly, may facilitate destabilization through midday and into the afternoon south and east of I-55. This could support gradually-increasing storm organization and intensification. That said, progged shear profiles still aren`t anything spectacular with the main mid/upper jet cores still relegated well to the west. Given this, it seems like the locally greatest threat for strong-severe storms exists across the eastern half of the CWA from about midday through the afternoon. In this scenario, deeper boundary layer mixing would also promote increasing southwesterly wind gusts, possibly pushing 40 mph. If the overnight complex fizzles prior to reaching our area, the severe threat would likely increase across more of the region, although this currently looks like a lower potential at this time based on the latest multi-model consensus. Today`s guidance paints a similar picture/evolution to things for Monday night into Tuesday as the main cold front will sweep west to east through the region Tuesday afternoon. Once again, a potential for mainly sub-severe morning convection exists, followed by a threat for more robust storm development on the advancing cold front midday into the afternoon. While deep layer shear is forecast to be a bit more significant than Monday, instability could once again be muted significantly by morning convection. In the wake of the cold front, breezy northwesterly winds will develop Tuesday/Tuesday night before turning north/northeasterly on Wednesday as high pressure builds into the region. A period of tranquil weather is in store until the end of the week and next weekend when the next series of disturbances will bring additional chances of showers and perhaps some thunderstorms to the area. Carlaw && .AVIATION /06Z TAFS THROUGH 12Z TUESDAY/... Issued at 100 AM CDT Mon May 18 2026 Forecast concerns for the terminals... - Line of showers and embedded thunderstorms to move through northern IL and northwest IN late tonight into Monday morning. A few storms could be strong with a threat for locally gusty winds. - Breezy south-southwest winds Monday afternoon with gusts around 25 kts. - Another period of showers and possible storms late Monday night into Tuesday morning. Latest radar imagery continues to show a line of showers and thunderstorms stretching from MN to KS that is racing towards northern IL and eventually northwest IN. Arrival time of this line continue to be around 09z at RFD and between 10-12z for the Chicago area terminals. While lightning trends within the line segment heading towards the terminals has been decreasing, recent AMDAR sounding out of MDW continue to show steep mid- level lapse rates (around 7-8 C/km) which could still support an occasional lightning strike as the line moves through. Additionally, a few stronger showers/storms are possible and could result in localized gusty winds and maybe some small hail. Once the line of showers/storms arrives, it should move through within 3-4 hours at each site. However, with the expected arrival time around daybreak there continues to be a chance that some renewed development could occur within the line as it traverses the area, especially south of I-80. If this occurs as guidance suggests then shower/storm activity could persist through the morning before things fully exit the area. It was for this reason that the long PROB30 was maintained, but hopefully we can refine this window as the line arrives. After the line exits the area around midday, breezy south- southwest winds will develop and persist through the afternoon. Gusts during this period look to generally be around 25 kts but locally higher gusts (upwards of 30kts) are possible. While there is still a non-zero chance (15-20%) for additional shower and/or thunderstorms to develop this afternoon, latest guidance trends have continued to back off on this scenario given that the better forcing for storms will be centered to our west in IA. That said, another round of showers and thunderstorms is expected to develop in IA this afternoon and move into northern IL and northwest IN late Monday night into Tuesday morning. Though, the coverage of these storms into our area looks much more limited (especially the thunder coverage) so have opted to introduce a PROB30 for SHRA in the 30-hour TAFs for now. Otherwise, expect VFR conditions to prevail through the period. Yack && .LOT WATCHES/WARNINGS/ADVISORIES... IL...None. IN...None. LM...Small Craft Advisory until 4 AM CDT early this morning for the IL and IN nearshore waters. && $$ Visit us at weather.gov/chicago