397 FXUS63 KDVN 301705 AFDDVN Area Forecast Discussion National Weather Service Quad Cities IA IL 1105 AM CST Fri Dec 30 2022 ...18z AVIATION UPDATE... .SYNOPSIS... Issued at 249 AM CST Fri Dec 30 2022 After a day of record setting, remarkably spring feeling weather, a cold front has now progressed through most of Iowa, and will be moving through Illinois before sunrise. High temperatures at all places today have already been set at Midnight, with temperatures falling to the upper 20s and lower 30s behind the cold front through 2 AM, likely falling to the lower 20s northwest to lower 30s east by sunrise. && .SHORT TERM...(Today and tonight) Issued at 249 AM CST Fri Dec 30 2022 Clouds will be the main problem for today's forecast, as models show cloudy skies through the day, but looking at satellite, we are more patchy than the models show behind the cold front. Thus, there is potential for more sun today, than models show, thus we're going to see CAA through the morning, but by afternoon, the temperatures may warm up to near 40 in places. This is mostly possible from Interstate 80 and south, but will need to be watched closely everywhere. On the other hand, if cloudy skies stay around through mid afternoon, many places in the northern 1/2 may stay near 32 or below. A difficult forecast, but benign, as winds will be generally light, and no precipitation will be expected. Tonight, with partly cloudy skies by evening, becoming cloudy through the night, it should be a quiet night in the 20s. If we do have a few clear hours this evening, upper teens could be seen, but we will stay near the 50% NBM for today, highs and lows today where the best clustering of percentiles are presented today. ERVIN .LONG TERM...(Saturday through Thursday) Issued at 249 AM CST Fri Dec 30 2022 A storm system will occur right after New Years. Temperatures generally above normal then cooling the second half of next week. Saturday/Saturday night Assessment...very low confidence on precipitation chances. A weak upper level disturbance will move through the area. Some solutions are generating precipitation while most are not. There is a fair amount of dry air aloft which raises questions on whether any precipitation will occur. The model consensus has slight chance pops for most of the area Saturday afternoon. Slight chance pops are north of I-80 and east of the Mississippi Saturday evening. Sunday/Sunday night Assessment...medium to high confidence The model consensus has dry conditions as high pressure quickly moves through the area ahead of the approaching storm system. Monday through Tuesday night Assessment...high confidence on a storm system in the Midwest. The global models have advertised a storm system moving through the Midwest for about a week. There are still some timing, track and evolution differences that would affect the sensible weather. The storm system will be strengthening as it approaches and the potential for a further north and west track is there along with additional slowing. There is a loose general agreement that much warmer than normal temperatures will push into the area with the storm system followed by much cooler temperatures as colder air wraps in behind the departing storm system. Right now the model consensus has chance to likely pops Monday, categorical pops Monday night, chance pops Tuesday and dry conditions Tuesday night. Although there are differences in timing/track the models seem to be converging on a signal pointing to Monday night as being the most likely time for precipitation. The surge of moisture coming north with the storm system is significant. The large scale synoptic picture suggests a widespread general rain across the area with heavy rain expected. Some rumbles of thunder are also possible, especially east of the Mississippi and south of I-80. Wednesday through Thursday Assessment...low confidence The model consensus has dry conditions for the area. The dry consensus is based on the CMC/GFS models which have minimal if any wrap around precipitation associated with the departing storm system. The ECMWF has wrap around precipitation Wednesday/Wednesday night. Interestingly the CMCE/GEFS/EPS have many members showing wrap around precipitation occurring Wednesday into Wednesday night. && .AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon) Issued at 1101 AM CST Fri Dec 30 2022 Any leftover MVFR stratus will gradually diminish this afternoon, with VFR conditions expected at all the terminals through tonight. Northwest winds around 10 knots will become light and variable this evening, and will persist through tonight. Winds will increase out of the southeast Saturday morning but will remain under 10 knots. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...Ervin SHORT TERM...Ervin LONG TERM...08 AVIATION...Speck