Area Forecast Discussion
Issued by NWS Central Illinois
Issued by NWS Central Illinois
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692 FXUS63 KILX 301810 AFDILX Area Forecast Discussion National Weather Service Lincoln IL Issued by National Weather Service Chicago IL 110 PM CDT Tue Apr 30 2024 .KEY MESSAGES... - Above normal temperatures will prevail across the area through next Tuesday May 7th, with Thursday being the warmest day with highs in the low to mid 80s and windy with southerly winds gusting 25-35 mph by Thu afternoon. - There is a chance of showers and thunderstorms late this evening and overnight, mainly over the IL river valley where a marginal risk of severe storms for gusty winds and hail west of the IL river from 10 pm to 2 am tonight. More widespread showers and thunderstorms with heavier rains expected Thursday afternoon into Friday morning. && .UPDATE... Issued at 1038 AM CDT Tue Apr 30 2024 Fog over southeastern portions of the CWA has burnt off and allowed dense fog advisory to expire as scheduled. Current forecast is in good shape with no updates planned for this afternoon`s forecast. Will be assessing the threat of showers and storms for tonight with the afternoon forecast. - Izzi && .DISCUSSION... Issued at 400 AM CDT Tue Apr 30 2024 A weakening cold front had pushed southeast of IL early this morning with its convection now mainly southeast of Indiana over western Ohio, central KY and mid TN. Lingering stratus clouds lifting NNE over Wabash river valley of southeast IL se of a Danville to Flora line. Widespread fog from Danville to Shelbyville southeast with dense fog common from Paris to Charleston/Mattoon to Shelbyville southeast where dense fog advisory continues through 9 am today. The fog should lift by mid morning in southeast IL with the stratus clouds scattering out over the Wabash river valley during this morning. Weak high pressure over IL early this morning to drift east over the Ohio and TN river valley this afternoon, with south to SW winds increasing and approaching breezier levels later today over the IL river valley. A very nice day expected overall with ample sunshine with highs in the mid to upper 70s and more comfortable dewpoints in the 50s. A weather system over MT and WY early this morning to track eastward into the upper MS river valley by midnight and have a cold front approaching nw IL, and moving through central IL overnight as it weakens. Have a better chance of showers and a few thunderstorms by late evening over the IL river valley, with these chances diminishing at it shifts into east central IL overnight. SPC day1 outlook has marginal risk of severe storms late this evening and early overnight from the IL river west for gusty winds and hail, while tornado threat and greater risk of severe storms is west of IL this evening. Southeast IL will likely stay dry tonight. Lows overnight in the upper 50s to around 60F. Another weak high pressure ridge over IL on Wed with upper level ridging into the Ohio and TN river valleys. This to bring fair wx and lighter winds on Wed with skies becoming partly sunny. Warm highs Wed in the upper 70s central IL and lower 80s in southeast IL. A warm front lifting northward over central IL overnight Wed night into Thu morning could bring isolated convection Wed night into Thu morning especially from I-55 west. Will see higher chances of showers and thunderstorms later Thu west of the IL river ahead of approaching storm system from the central plains. Breezy southerly winds develop in warm sector on Thu with gusts 25-35 mph likely by Thu afternoon. This to bring warm highs in the low to mid 80s, a bit shy of record highs in the lower 90s on May 2nd. Surface low pressure developing over southeast CO by sunset Wed to eject ne toward the MN/WI/IA border by sunset Thu and pull a cold front east through central IL during Thu night, and thru southeast IL Fri morning. This front to likely bring showers and thunderstorms eastward over the IL river valley late Thu afternoon into Thu evening and across rest of central IL during Thu night. Best chances for convection in southeast IL is late Thu night into Friday. SPC day3 outlook for Thu/Thu night keeps marginal risk west of CWA, except reaching near Galesburg by Thu evening. WPC has slight to marginal risk of excessive rainfall over IL Thu night with higher rainfall amounts expected over the IL river valley where over 1 inch expected. Convection chances to diminish behind the cold front from west to east during Friday, with chance of showers possibly lingering into Fri evening over southeast IL. Highs Friday in the lower 70s in central IL and mid 70s in southeast IL. Models still not in the best agreement with the weekend forecast as blended models now giving a chance of showers and isolated thunderstorms on Saturday afternoon and Sat night which was dry with yesterdays runs. And latest trends for chances of shower and thunderstorms on Sunday have lowered and shifted southward. Highs this weekend in the 70s with southeast IL near 80F on Saturday. 07 && .AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/... Issued at 107 PM CDT Tue Apr 30 2024 The primary aviation weather concerns through the 18Z TAF period include: * A wave of showers and thunderstorms late tonight A broken line of showers and thunderstorms will move across central IL late tonight. Precip is expected to approach PIA from the west as early as 04Z and progress eastward through the night. Thunder chances will be slightly better along and west of I-55 where it`s not out of the question that pockets of heavier downpours could pull cigs down into MVFR territory for a brief time. Rain should clear all sites by the middle of the overnight with no precip in the forecast for Wednesday. Meanwhile, southwest winds below 10 kt will go more southerly late this afternoon. They`ll ramp up late this evening in the vicinity of the precip with gusts likely to reach the 20 to 25 kt range at times. They`ll step down through the early morning with the better part of Wednesday seeing SW winds near or below 10 kt. Doom && .ILX WATCHES/WARNINGS/ADVISORIES... None. && $$