423 FXUS63 KILX 060312 AFDILX Area Forecast Discussion National Weather Service Lincoln IL 912 PM CST Sun Mar 5 2017 .UPDATE... Issued at 912 PM CST Sun Mar 5 2017 Lots of clouds over the area this evening and am expecting this to continue during the overnight hours. Cloud cover and gusty winds will keep temps from dropping too much more than what they have already fallen to. Gusty winds will also continue overnight. Therefore current forecast is handling current situation well. No update planned at this time. && .SHORT TERM...(This evening through Monday) ISSUED AT 300 PM CST Sun Mar 5 2017 Strong southerly winds of 15-30 mph and gusts of 25-40 mph prevailed this afternoon across central IL and will continue Monday ahead of an approaching cold front. These strong southerly winds gave milder temperatures in the mid 50s to mid 60s, despite mostly cloudy skies. Weakening 1038 mb high pressure over central Quebec and ridging southward toward eastern VA/NC. Deepening 992 mb surface low pressure was over central MT. Latest forecast models deepen surface low pressure of 975 mb over ne ND by sunset Monday while bringing a cold front east across western IA and nw MO. Increasing low level moisture into IL ahead of this front with persistent strong southerly flow. This will bring small chances of light rain showers into southeast IL overnight and across CWA during Monday morning. Continued chances of thunderstorms over areas west of I-57 Mon afternoon, mainly late. Milder lows tonight in the upper 40s and lower 50s, which is a few degrees above normal highs for early March. Mild highs Monday in the mid to upper 60s with west central IL near 70F. .LONG TERM...(Monday night through Sunday) ISSUED AT 300 PM CST Sun Mar 5 2017 Showers and thunderstorms will be in the area to start the period ahead of a cold front that will be approaching western Illinois at 00Z Tuesday. The showers and storms will be most widespread across the forecast area during the evening, but will begin to taper off from northwest to southeast overnight in the wake of the cold front. Recent model runs suggest a few severe storms are possible, mainly Monday evening, with pre-frontal bulk shear values of 50-60 kts and MU CAPE values possibly reaching 1000 j/kg or a little higher. The best chances will occur over west-central Illinois where the instability will be higher. Locally heavy rainfall is also a threat with precipitable water values of 1.25-1.5 inches ahead of the front. The rainfall threat will quickly come to an end Tuesday morning, if it has not already done so, as the front races to the east. Gusty westerly winds are expected in the wake of the front Tuesday, with gusts to 40 mph possible by Tuesday afternoon. Forecast soundings suggest fairly deep mixing will develop to support these wind gusts, but this will also likely result in low Relative Humidity values in the afternoon. We'll have to watch the threat for high fire danger Tuesday afternoon if current model trends persist. The models continue to struggle with the precipitation risk for the end of the week into the weekend. A fast west-northwest flow regime aloft will be in place for most of the week behind the early week storm. Model spread and run-to-run variability has been high with the low amplitude waves expected within this pattern. The best chance for organized precipitation (mainly rain) at this point appears to be Saturday. Although a risk also exists late Thursday/Thursday night, and possibly Friday. Numerous adjustments to the current forecast will likely be needed as the low amplitude waves are better resolved by the guidance. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 543 PM CST Sun Mar 5 2017 MVFR cigs have arrived at all sites except PIA and CMI. However, CMI should get there soon given that other MTRs to the west are already MVFR. Based on HRRR forecast, PIA should see MVFR cigs starting around 02z. MVFR cigs will continue rest of the night and through tomorrow as lots of low level moisture will advect into the area from the south tonight and continue through tomorrow. Models differ on if it will be continuous or have a period of better cigs at SPI and DEC overnight. Have decided to stay continuous at all sites with cig height dropping to around 1.5kft overnight and continuing through tomorrow. Models show possible light precip in the area tomorrow so will keep the VCSH already in the TAFs. Winds will remain gusty out of the south overnight and through tomorrow. Cig heights could improve tomorrow afternoon, but models differ on this solution. Will decide how to handle for next issuance. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Auten SHORT TERM...07 LONG TERM...Bak AVIATION...Auten