947 FXUS63 KILX 142033 AFDILX Area Forecast Discussion National Weather Service Lincoln IL 233 PM CST Fri Dec 14 2018 .SHORT TERM...(This evening through Saturday) ISSUED AT 233 PM CST Fri Dec 14 2018 Fog has been a real headache today. Short-term models have not handled the stubborn visibilities well at all. Increased gradient was expected to increase winds and mixing leading to improvement as afternoon proceeded. That has obviously not occurred at many locations despite winds gusting 10-15 kts. With KGBG currently at m1/4sm and KBMI remain at 1/16sm through much of the day, the low sun angle, and sunset approaching, see no reason that for rapid improvements. Will keep current dense fog advisory in place through 03z and have the evening shift re-evaluate as 00z models arrive - though models today haven't been a whole lot of help. At this time some partial clearing is still possible late tonight in KGBG area as clearing line currently in ern IA approaches. If we do get some drier air into that area, temps may fall below freezing. Otherwise, areas with fog and clouds should remain above freezing and freezing fog is not expected. Gradual clearing is expected Saturday as the upper low pulls away from IL and drier air advects into northwest IL and then spreads southeast. Weak cold advection will offset clearing in northwest counties and highs should be rather uniform across central and southeast IL, generally in the middle to upper 40s. && .LONG TERM...(Saturday night through Friday) ISSUED AT 233 PM CST Fri Dec 14 2018 Upper low moving into mid-Atlantic should continue off to the east as kicker short-wave progresses in nrn stream. Cold air remains bottled up near the Canadian border and above normal temperatures are expected to persist through early next week. 500mb heights and 850 temps increase through Wednesday as flow becomes more meridonal in response to a digging trough over the western U.S. As mid-week arrives, models are relatively consistent in progressing energy over the west into the midwest as it phases with a deepening nrn stream system. Amount of pcpn and cold advection in the wake of the system is dependent on the amount of phasing that occurs. As usual the GFS is phasing the energy more than ECMWF and reflects a stronger system and colder temps in the wake of the low. The GEFS envelope mean is even colder with boundary layer temps for the end of the week. With so much range in solutions, will go with a blend. Some mixed pcpn is possible in the northern forecast area Wednesday Night but with sfc temps expected to remain above freezing no accumulations are expected. && .AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon) Issued at 1118 AM CST Fri Dec 14 2018 With upper low rotating south of IL, we remain in moist northeast flow through the TAF period. IFR clouds and vsbys still extend back to the Mississippi Valley and with low sun angle and weak vort lobes rotating around the low see little reason that conditions will improve significantly before sunset. Models for the most part seem a bit too agressive in improving conditions. With a northeast surge expected later tonight, vsbys may improve some but will clouds will likely remain IFR/MVFR until after sunrise Saturday. && .ILX WATCHES/WARNINGS/ADVISORIES... Dense Fog Advisory until 9 PM CST this evening for ILZ027>031- 036>038-040>043-047>051. && $$ SHORT TERM...Barker LONG TERM...Barker AVIATION...Barker