Area Forecast Discussion
Issued by NWS Central Illinois
Issued by NWS Central Illinois
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073 FXUS63 KILX 092026 AFDILX Area Forecast Discussion...Updated National Weather Service Lincoln IL 326 PM CDT Sun Jun 9 2024 .KEY MESSAGES... - Breezy northwest winds with gusts up to 30 mph north of I-70 could lead to blowing dust in open areas into early evening. - Comfortable temperatures will persist through Tuesday night before things turn very warm and more humid Wednesday through early next week. - Next best chance of thunderstorms is Thursday night, with 20-40% chance from I-70 north. Slight chance of severe storms Thu evening over the IL river valley north of I-72. && .DISCUSSION... Issued at 315 PM CDT Sun Jun 9 2024 Mid afternoon surface map shows 1027 mb high pressure over central Sasketchewan and riding southward across the Central Plains. Cold front had pushed into the southern TN river valley and into central AR. Radar mosaic shows convection was generally south of I-64 in southern IL into central/sw KY, southeast MO and into northern parts of AR/TN. Cirrus shield was along and south of a Flora to Robinson line and retreating southward. Scattered cumulus clouds were over northern CWA with high bases above 7k ft. Breezy NW winds gusting to around 30 mph over central IL. Temps were in the upper 70s and lower 80s, with mildest temps from I-57 west and coolest temps in cloudier areas from Clay, Richland and Lawrence counties south. Much drier air advecting into central IL with dewpoints ranging from upper 30s and lower 40s from Lacon and Pontiac north to the mid 50s along and south of highway 50 in southeast IL. Latest CAMs shows a short wave trof shifting southward across the Great Lakes tonight. Diurnally driven cumulus clouds north of I-72 to dissipate at sundown as breezy NW winds diminish and turn north by overnight. Though a band of scattered to broken stratocumulus clouds over WI to move southward over central IL overnight ahead of trof. Lows tonight in the mid 50s, with some upper 50s from highway 50 south. Monday will be the coolest day of this week with strong upper level trof over the central and eastern Great Lakes and Ohio river valley and into New England. Scattered to broken stratocumulus clouds to decrease from nw to se during the day Monday. High Monday in the low to mid 70s which is about 10 degrees cooler than normal. Weak high pressure around 1018 mb to drift over IL Monday night and bring a fair/cool light with light winds. Lows Monday night in the upper 40s to around 50F. Pleasant day expected Tuesday with weak upper level ridging over IL and surface high pressure ridge nearby. A weather system moving eastward over the upper MS river valley on Tue to bring some increase clouds over northern CWA especially from I-74 north while its convection to stay nw of CWA on Tue. Highs Tue in the upper 70s to near 80F with fairly light winds becoming sw. Dry conditions continue Tue night with lows in the lower 60s from I-55 west and mid 50s in southeast IL. A flat mid/upper level ridging building over the central and southern Rockies and into the central and southern Plains during mid week to bring much warmer temperatures into central/se IL Wed and on. Highs Wed in the mid to upper 80s, warmest from I-55 west. Humidity levels not too bad yet on Wed with dewpoints in the 50s and lower 60s. Convection chances appears to stay nw of CWA Wed through Thu morning over the Great Lakes and upper Midwest region. A frontal system tracking south/se toward central IL Thu night to bring 20-30% chance of thunderstorms by late Thu afternoon over northern CWA and into much of central IL during Thu night. SPC has slight risk of severe storms nw CWA Thu night especially during Thu evening where instability and wind shear is forecast to be greater. Hot on Thu with highs around 90F and more humid with dewpoints in the 60s with sw breezes. Weakening cold front presses se toward the Ohio river during Friday with best chances of convection shifting se of central IL. Still hot on Friday with highs in the upper 80s/lower 90s, warmest in southeast IL. Then dry and slightly cooler and less humid Fri night and Sat with strong upper level ridging building over the mid MS and Ohio river valley as 500 mb heights rise to 588 meters or higher. Breezy southerly winds return more summertime heat and humidity next Sunday and Monday with highs 90 to 95F appearing likely. 07 && .AVIATION... (For the 18z TAFs through 18z Monday Afternoon) Issued at 1245 PM CDT Sun Jun 9 2024 VFR conditions are generally forecast to continue across the central IL airports through 18Z/1 pm Monday. Breezy NW winds 10-15 kts and gusting 18-25 kts this afternoon and early evening, to diminish to 5-10 kt after sunset, and veer north to NNE overnight. Few to scattered high cumulus clouds with 5-7k ft bases this afternoon to dissipate at sunset, while scattered cirrus clouds along I-72 push southward during mid/late afternoon. A trough axis/upper system dropping a corridor of 3 to 5k ft stratocumulus clouds southward from central WI across central IL during overnight. Probabilities for ceilings to fall into MVFR flight conditions is less than 50% as of now, with higher chances ne of BMI and CMI by dawn Monday. 07 && .ILX WATCHES/WARNINGS/ADVISORIES... None. && $$