Area Forecast Discussion
Issued by NWS Chicago, IL
Issued by NWS Chicago, IL
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567 FXUS63 KLOT 150507 AFDLOT Area Forecast Discussion National Weather Service Chicago/Romeoville, IL 1107 PM CST Sat Feb 14 2026 .KEY MESSAGES... - Rain is expected across central IL/IN and may extend as far north as US-24 this evening and overnight. - Above average temperatures continue through midweek then turn colder toward the end of the week. - Periodic precipitation chances exist mid to late next week (~20-40% chance). && .DISCUSSION... Issued at 300 PM CST Sat Feb 14 2026 Through Tonight: Expansive stratus extending north of an approaching disturbance slowed diurnal warming across the area for much of the day. However, a brief southward shift in the northern edge of the clouds has allowed sun to shine over far northern Illinois intermittently where temperatures have since warmed into the lower 50s. Elsewhere temperatures are still in the mid to upper 40s and may struggle to warm much more prior to sunset. A weak lake breeze hugging the immediate lakeshore will also keep temperatures in the lower to mid 40s there. Looking ahead to tonight, dry conditions are expected for most of the area. We are monitoring an expansive area of rain currently lifting into central Illinois. Based on the latest hi-res model trends, have held onto rain chances for locales south of US-24 where the northern periphery of the rain shield could briefly lift across. Rainfall amounts should remain light given the limited duration, under 0.15". Increasing low-level moisture in the wake of the departing system could allow for patchy fog development (well south of I-80) as temperatures cool overnight. Sunday: A weak mid-level short-wave will dive across the area late tonight into early Sunday morning with an associated surface trough axis turning winds northwest. This will actually lead to warmer upstream air advecting into the area on Sunday. In contrast to today`s temperature forecast which was more uncertain due to the cloud cover, temperatures look to more solidly warm into the 50s across the area, including near the lakeshore. In fact, some of the warmer guidance (RAP/HRRR) suggest some areas could reach 60. An inland push of the lake breeze will cut the warmth short near the lakeshore where temperatures will quickly fall back into the 40s in the afternoon. Monday and Tuesday: Expansive upper-level ridging will build across the region on Monday and set the stage for the warmest day of the year so far with highs potentially in the upper 50s to lower 60s areawide (this would break record highs for Feb 16 at both Rockford and Chicago-O`Hare). As is often the case on anomalously warm days it will likely be paired with gusty southwest winds potentially gusting up to 30-35 mph in the afternoon. Tuesday night through Wednesday morning: The western CONUS upper trough begins to eject off the Rockies toward midweek with lee cyclogenesis expected across the northern Plains. This feature is then expected to drift east across the Upper Midwest with an expansive region of warm advective precipitation expected to develop out ahead of it. This could lead to a period of rain late Tuesday night into Wednesday morning over portions of the area (with the wintry precipitation likely remaining north of the WI/IL stateline). A brief period of elevated instability could support a few embedded lightning strikes, however, given lower confidence, opted to maintain a cap of 15% on thunder chances. Wednesday through the end of the week: Confidence in the details decreases in the wake of the Tuesday night system with differences in how far north the various subsequent systems track, with the local area potentially residing on either side or right along it. Opted to not make big changes to the blended guidance for now, which leans toward the warmer guidance on Wednesday with highs potentially well into the 60s (upper 60s south of I-80) with periodic low precip chances (20-40%). Temperatures then generally trend colder (and more seasonable) toward the end of the week which could feature wintry precipitation depending on where the aforementioned systems track. Petr && .AVIATION /06Z TAFS THROUGH 12Z MONDAY/... Issued at 1107 PM CST Sat Feb 14 2026 Key Aviation Messages for the 06Z TAFs: - Some patchy BR possible prior to sunrise at RFD/GYY. - Low confidence in weak lake breeze late Sunday afternoon/early evening, mainly at MDW and GYY though can`t rule out ORD. Surface low pressure was over Arkansas late Saturday evening, and will continue to track east through Sunday morning with its associated area of rain and lower vis/cig conditions remaining well south of the terminals. North of the low, a weak and diffuse ridge of surface high pressure will linger across the terminals, and will support light (<5 kt) south-southwest winds overnight. Winds will eventually turn more westerly toward daybreak, and eventually west-northwest or northwest behind a surface low pressure trough which will pass midday. While these winds are only expected to be around 10 kts, model guidance continues to trend weaker with a lake breeze which looks to be confined to near the IL shore and into northwest IN late in the day/early evening. Have indicated a brief shift to northeast winds at GYY and MDW in the 23-00Z timeframe, with lower confidence of a sharper wind shift at ORD. It does appear however that winds will weaken and flop to south-southwest at all sites early-mid Sunday evening (including ORD). Have started to see some light (6-7SM) BR developing at KRFD at issuance time, where high clouds have started to thin/scatter. There could be some brief MVFR vis there, though with winds eventually turning southwest and increasing slightly and a patch of VFR mid-level clouds expected to spread in from eastern IA predawn, am not currently expecting fog to become widespread or significantly denser. Surface dew points are also a bit higher at GYY, thus some MVFR BR can`t be ruled out there prior to sunrise. Otherwise, VFR conditions are expected to prevail through the period. Ratzer && .LOT WATCHES/WARNINGS/ADVISORIES... IL...None. IN...None. LM...None. && $$ Visit us at weather.gov/chicago