Area Forecast Discussion
Issued by NWS Central Illinois
Issued by NWS Central Illinois
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735 FXUS63 KILX 141057 AFDILX Area Forecast Discussion National Weather Service Lincoln IL 557 AM CDT Fri Aug 14 2026 .KEY MESSAGES... - Flash flooding is a concern along and north of the I-74 corridor ongoing. Some locations have received 2-4 inches so far. - There is an area of convection moving south across central and southeastern IL this morning that poses a heavy rain and damaging wind threat. The next round of convection will move in late this evening into the overnight hours. A slight risk for severe weather is in place for the northwestern part of our CWA from the SPC. - Heat index values of 105 to 110 degrees will continue into the weekend each afternoon, in areas near and south of I-72. The heat is expected to spread northward across the forecast area by Saturday. && .DISCUSSION... Issued at 152 AM CDT Fri Aug 14 2026 The next round of heavy rain and strong storms have entered the northern part of the CWA. It will continue to sink southward throughout the overnight hours into the morning. The environment is still quite unstable and as these storms push south, they should move into an area of stronger CAPE values. Effective wind shear is around 45 knots as of the most recent mesoanalysis from SPC where the storms are located. Damaging winds is the main concern with the strongest storms, but some small hail is possible as well. The next round of convection will move in late this evening into the overnight hours. A slight risk for severe weather is in place for the northwestern part of our CWA from the SPC. Along with the severe risk, we are also concerned for some flooding. There is a flood watch out until 15z this morning. PWATs are around 2-2.2 inches. We have been quite saturated as of late. Some areas cannot take much more without becoming inundated. Along and north of I-74, the FFG is much lower (6 hr: 2-2.5 inches, 3 hr: 1-2.5 inches) than in the southern half of the CWA, since they have received much of the rain in the last day or so. The area around I-74 to Danville has gotten ~2-5 inches of rain in the last 24 hours based off of MRMS estimates. WPC has put our northwestern counties in a moderate risk ERO today. Temperatures remain hot as we make our way into the weekend. There is a heat advisory for Scott County to Clark County (and south) that is valid through Sunday. Further expansion north of the advisory is possible as we go forward in time and get a better grasp of how the next few rounds of MCS activity will evolve, both spatially and temporally. Heat indices of 100-110 degrees are forecast through Sunday, but how far north these heat indices get will depend solely on the convection. There is a marginal risk for severe weather again tomorrow area-wide and again on Sunday for areas south of a Schuyler to McLean County line with a similar environment in place as previous days. The forecast will continue to evolve as we get newer runs of the models. Next week may bring us a break in the active weather and the heat briefly. Some guidance suggests a high pressure area setting up over the Upper Mississippi Valley / Great Lakes region by Monday, behind a cold front that is set to move through central IL during the day. Temperatures starting Monday into much of the next week will be mainly in the upper 70s to 80s for highs and 60s to low 70s for lows. && .AVIATION /12Z TAFS THROUGH 12Z SATURDAY/... Issued at 557 AM CDT Fri Aug 14 2026 IFR ceilings are in place at KPIA-KBMI and are expected to remain through mid-late morning, then MVFR through much of the afternoon. Periods of TSRA with locally heavy rain and gusty winds will affect the terminals through mid-late morning, with bouts if IFR-LIFR under the more intense storms. Much of the rest of the day will be VFR with light (and at times, variable) winds. The next complex of thunderstorms will move in overnight tonight, mainly affecting PIA and BMI within the 12z period. && .ILX WATCHES/WARNINGS/ADVISORIES... Flood Watch until 10 AM CDT this morning for ILZ027>031-037- 038-045-046. Heat Advisory until 8 PM CDT Sunday for ILZ049>052-061>063- 066>068-071>073. && $$ KEY MESSAGES...Copple DISCUSSION...Copple AVIATION...Copple