Area Forecast Discussion
Issued by NWS Central Illinois
Issued by NWS Central Illinois
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133 FXUS63 KILX 110722 AFDILX Area Forecast Discussion National Weather Service Lincoln IL 122 AM CST Tue Nov 11 2025 .KEY MESSAGES... - Breezy today with southwesterly winds gusting 25-35 mph. There is a low chance (10-30%) for gusts as high as 40 mph. - A gradual warming trend begins today and continues through Saturday. Highs today will range from low 40s in east-central Illinois to low 50s in west-central Illinois. By Saturday, there is a high chance (75-90%) of temperatures reaching the 70s. && .DISCUSSION... Issued at 119 AM CST Tue Nov 11 2025 *** TODAY *** A NW flow pattern is in place aloft, with a developing upper ridge over the SW US and deep troughing centered over New England. A weak shortwave traversing the NW flow was located over the Dakotas as of 1am/07z, with upper level cloud cover streaming well downstream. Expect increasing cloud cover leading to mostly cloudy skies through this morning, followed by decreasing cloud cover in the afternoon. Fcst soundings continue to show a well-saturated layer aloft, so this will be a rather thick cloud deck. Bases are expected to be 8- 10 kft above the sfc though, and with dry low- level air it will be difficult for any precip to reach the sfc. Despite my skepticism, did leave a mention of isolated flurries in the forecast through midday. A tight pressure gradient will exist today between strong sfc high pressure (around 1032mb) near the Gulf Coast and a 996 mb sfc low over Ontario. This will result in breezy SSW winds today, with a high chance (over 80%) of peak gusts of 30-35 mph. GFS fcst soundings suggest even higher gusts (over 40 mph) could mix down, but will note this is a bit of an outlier, even when comparing with the GEFS members (generally 25-35 mph gusts). HREF probs only have a 10-25% chance for gusts over 40 mph. Afternoon relative humidity drops to around 30-35%, which combined with the gusts could lead to some minor risk of unwanted fire spread. The only other notable forecast challenge in the short-term is the impact of snow cover in east-central IL on the temperature forecast. The low temp forecast for this morning was lowered into the teens, and current obs are around 20 degrees over snow cover compared to mid 20s elsewhere. Not confident as to how much snow cover will limit temps today given the breezy southwest winds, but did nudge the forecast a few degrees cooler over the snow cover. Forecast highs range from upper 40s/low 50s west of I-55 to near 40 in areas of snow. Lows tonight will be near freezing. *** REST OF THE WEEK *** Upper ridging gradually amplifies out west and slides east by the late week period, and the warming trend is little changed from previous forecasts. Highs on Wed-Thurs will be closer to seasonable values, in the mid 50s to low 60s, followed by above normal temps Fri into the weekend. Temps are still expected to reach the 70s on Sat (75-90% chance), which could approach record territory in some spots. One minor change to the forecast was the introduction of low chance (15-20%) precip south of I-70 late Thurs night/early Fri AM. This is in response to LLJ forcing. If this precip does develop, it`s unlikely to amount to more than a few hundredths of rain. A better chance of rain still appears possible this weekend or early next week, as a deep trough over the western US starts to emerge onto the Plains. Forecast confidence remains quite low with this system. Yesterday, models depicted a split flow pattern with a phased wave ejection, but now models depict the southern wave cutting off over the desert SW and taking much longer to reach our region. The latest NBM is dry through the day on Sat, with PoPs slowly increasing overnight and reaching the 30-40% chance range for Sun-Mon. I`d expect the PoP timing to narrow and values to increase as the system comes into better focus. The probability of total rainfall amounts of 1" is 10-30% through Tuesday morning (highest south of I-70). It is too early to meaningfully assess the severe storm potential due to the significant model differences in this system`s evolution. Erwin && .AVIATION... (For the 06z TAFs through 06z Tuesday Night) Issued at 1050 PM CST Mon Nov 10 2025 VFR conditions will prevail at all sites next 24hrs. Scattered high clouds will prevail overnight, but mid clouds will advect in and become overcast through the morning hours and during the afternoon. Clouds will scatter out late afternoon and then clear skies expected during the evening hours. Winds will be light and variable overnight and then become more south-southwesterly tomorrow into tomorrow evening. Wind speeds tomorrow will increase with gusts of 25-30kts tomorrow late morning through afternoon. Speeds decrease late afternoon into the evening hours with speeds of 09-11kts. Auten && .ILX WATCHES/WARNINGS/ADVISORIES... None. && $$