756 FXUS63 KFSD 302250 AFDFSD Area Forecast Discussion National Weather Service Sioux Falls SD 450 PM CST Sat Dec 30 2017 .SHORT TERM...(This evening through Sunday) Issued at 449 PM CST Sat Dec 30 2017 Quite simply cold. The main story continues to be the excessive cold weather, with dry weather expected Sunday and beyond. In the near term however, light snow is expected to spread across the region this evening into the early morning hours. The light snow band will be focused along a mid level boundary set up near the Missouri Valley along with the arrival of a shortwave. Moisture and the progressive nature of this wave remains a somewhat limiting factor to snowfall amounts, however with low and mid level temperatures squarely in the dendritic growth zone, expect very high snowfall ratios on the order of 20+:1. Expect a quick 1 to 3 inches of snowfall along and south of a Huron to Sioux Falls to Spencer IA line. Heaviest amouts will be across south central SD/near the Missouri River. Across the northeast North of this line, only a dusting to around a half inch can be expected. Light snow will quickly come to an end in the early morning hour in our east, and prior to midnight east of I-29. Winds will remain relatively light at less than 10 mph, so blowing snow should not be a concern, however reductions in visibility is likely in snowfall, as well as slick, snow covered roadways. .LONG TERM...(Sunday night through Saturday) Issued at 449 PM CST Sat Dec 30 2017 Temperatures will be extremely cold into New Year's Day with lows tonight from -15 to -22 and dropping even colder to -18 to -26 on Sunday night. Readings will be particularly cold for any New Year's Eve festivities. Skies will clear from north of south during the day Sunday, but with high reflectivity of snowpack and a 1050mb high building over the northern Plains, temperatures will struggle to even reach the single digits below zero. As a result, wind chills be be well into the chill warning criteria late tonight, and stick there into the morning of New Years Day. It is likely that readings will bump into the advisory category briefly during the day, but given the short time frame of this "improvement", will keep things warning from midnight tonight through noon Monday for simplicity's sake. Dry weather is expected through this period. Temperatures moderate a little on Tuesday, with highs reaching the teens and lower 20s, however this warming trend will be short-lived. Another cold front drops across the northern Plains on Tuesday night, but is expected to be a dry passage, with moisture cut off from the region. Highs remain above zero Wednesday into Friday, but generally in the single digits or teens, while lows remain below zero. && .AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon) Issued at 1200 PM CST Sat Dec 30 2017 Snow will begin this evening for much of the area. During a 2 to 3 hour window, visibilities and ceilings will likely fall to IFR or LIFR conditions, with only light snow and MVFR conditions on either side of that window. Timing will vary based on location, starting in the west and moving east through the evening. Snow will exit the region by 31/0900z. Only light accumulations are expected. Light north winds with cold conditions continue through Sunday. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...Wind Chill Warning from midnight tonight to noon CST Monday for SDZ038>040-050-052>071. Wind Chill Advisory until midnight CST tonight for SDZ038>040- 050-052>071. MN...Wind Chill Warning from midnight tonight to noon CST Monday for MNZ071-072-080-081-089-090-097-098. Wind Chill Advisory until midnight CST tonight for MNZ071-072- 080-081-089-090-097-098. IA...Wind Chill Warning from midnight tonight to noon CST Monday for IAZ001>003-012>014-020>022-031-032. Wind Chill Advisory until midnight CST tonight for IAZ001>003- 012>014-020>022-031-032. NE...Wind Chill Warning from midnight tonight to noon CST Monday for NEZ013-014. Wind Chill Advisory until midnight CST tonight for NEZ013-014. && $$ SHORT TERM... LONG TERM... AVIATION...VandenBoogart