286 FXUS63 KFSD 182326 AFDFSD AREA FORECAST DISCUSSION National Weather Service Sioux Falls SD 526 PM CST Fri Nov 18 2022 .SHORT TERM...(This Evening through Saturday Night) Issued at 154 PM CST Fri Nov 18 2022 Key Messages: - Breezy westerly winds will decrease into the evening hours, becoming breezy again behind a passing cold front overnight. - Cold wind chills on either side of 0 degrees Saturday morning - Chances for light snow return along and behind passing cold front into Saturday morning, amounts under half an inch expected. - Warmer and more seasonal Sunday into the workweek Mostly clear skies this afternoon aside from some upper level cirrus, with a passing high pressure off to our south late this afternoon causing winds to temporarily shift to be out of the southwest. These winds will bring up some marginally warmer air, leading to afternoon highs in the upper teens to mid 20s. Areas east of I-29 have the best chance of setting new low max temperatures as their records are also in the teens. While there will be a lull in winds for areas south of I-90 this evening, north of I-90 will see breezy winds continue ahead of the approaching cold front. Right around midnight, the front will be approaching the I-90 corridor from the north, with breezy west-northwest wind coming in quickly behind it. Light snow is also expected to form along and behind the front, and given the breezy winds will likely see reductions in visibility while snow is falling. Given the non-zero CAPE values, can't rule out a more showery nature rather than stratiform snow, so be on the lookout for quickly changing conditions. While not quite as frigid as Friday morning, another brisk morning is expected Saturday morning with temperatures in the upper single digits to lower teens. Given the reinvigoration of breezy northwesterly winds behind this push of cooler air, wind chills on either size of 0 degrees are again expected. Chances for light snow continue throughout the morning hours as positive vorticity advection in the mid levels moves across the region behind the cold front, though including the overnight snow only up to half an inch of snow is expected. Chances for snow will be clearing out by late morning with cloud coverage also expected to decrease leading to partly sunny skies for the rest of the day. With the fresh shot of cooler air, Saturday will be the last day for this stretch with afternoon highs in the upper teens to mid 20s. Winds decrease into the evening hours, with another cold night expected. .LONG TERM...(Sunday through Friday) Issued at 154 PM CST Fri Nov 18 2022 Predominantly northwest upper flow will remain over the area through the long term period, with cool and dry weather continuing. The only shortwave feature of note moves through the region Thursday, but there is minimal moisture return ahead of it, and the preponderance of guidance keeps precipitation well to the north/east of the area where column saturation is more likely to occur. There are no targets of opportunity with respect to modifying the consensus NBM guidance, so made no substantive changes to the forecast. && .AVIATION...(For the 00Z TAFS through 00Z Saturday Evening) Issued at 515 PM CST Fri Nov 18 2022 Cold front passing through the area tonight leads to a few aviation concerns. LLWS is possible across the area as wind direction becomes more northwesterly, and if gusts diminish or briefly end, speed shear is also a concern. Additionally, expect VFR conditions to diminish (or at least become more scattered/patchy) as stratus deck returns, leading to MVFR ceilings. Light snow chances return late tonight and into Saturday as well, which could briefly cause visibility restrictions. Any accumulations are expected to be light. Northwesterly winds remain strong (gusts around 25-30 kts) into Saturday evening, with gusts tapering off toward the very end of the period and a transition back to more westerly direction. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. IA...None. NE...None. && $$ SHORT TERM... LONG TERM... AVIATION...SG