170 FXUS63 KFSD 110937 AFDFSD AREA FORECAST DISCUSSION National Weather Service Sioux Falls SD 337 AM CST Sat Nov 11 2023 .DISCUSSION... Issued at 333 AM CST Sat Nov 11 2023 KEY MESSAGES: 1. Temperatures moderating to above normal levels into the middle of next week. 2. Sprinkles possible east of Interstate 29 today, otherwise dry conditions are expected into next week. 3. With above normal temperatures and occasional breezy periods, there will be an elevated fire danger each afternoon. Surface low pressure over southwestern SD early this morning will push to the east through the day, becoming situated over eastern SD by this evening. In conjunction with this, a warm front will lift across our area, bringing moderating temperatures by this afternoon. With moderating 925 mb temperatures in the warm air advection regime, highs will top out around 50 north of Interstate 90 to upper 50s through the central and lower MO River corridor. Aloft, an upper level shortwave will track across the region during the day. This and midlevel warm air advection provided by a 40 kt low level jet oriented from eastern NE into south central MN could produce a few sprinkles east of Interstate 29 in the afternoon. Do not expect much in the way of measurable precipitation with model soundings indicating a good bit of low level dry air in place across the area. With the low level jet overhead and a steep surface pressure gradient out ahead of the aforementioned surface low, it will be breezy from the Interstate 29 corridor and eastward. This will result in an enhanced fire danger over that area during the afternoon. A weak cold front will sweep across the region on Sunday. This will have little impact on the sensible weather other than producing somewhat breezy northwesterly winds in the cold air advection regime, along with drier air advecting in behind the front. This will result in lower afternoon dew points (30-40%) as compared to today. Thus, even with lighter winds than today, there will again be an enhanced fire danger. The weak cold air advection will have little impact on 925 mb temperatures, and highs be in the upper 50s to lower 60s. The theme for Monday through Thursday of next week will be continuing above normal temperatures as upper level ridging builds across the region for the beginning of the week - transitioning to a more zonal flow by midweek. Both NAEFS and ECMWF ensembles indicate 850-500 mb temperatures in the 90th percentile with respect to climatology through this period. This will play out to much of our area having highs into the 60s on those days - which is around 10 to 15 degrees above normal for this time of year. Unfortunately it looks to remain dry through the week. With the above normal temperatures, lack of moisture, and some breezy days (Monday/Tuesday/Thursday), the fire danger will likely be enhanced each day. Models are suggesting that an upper level trough will sweep into the Northern Plains by the end of next week, and this could bring a return to more seasonable temperatures. && .AVIATION...(For the 06Z TAFS through 06Z Saturday Night) Issued at 1044 PM CST Fri Nov 10 2023 MVFR stratus has moved off to the northeast, leaving VFR conditions across the area tonight. High clouds are moving in from the east, with some mid level clouds east of I-29. Expect mid and high clouds to prevail through tomorrow night. Southeast winds expected tonight, increasing into the mid morning hours. Gusts around 20 to 25 knots prevail. LLWS is expected at KSUX and adjacent areas of the MO Valley and northwestern IA, and could see marginal LLWS conditions at KFSD, but confidence is too low to include at this time. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. IA...None. NE...None. && $$ DISCUSSION...JM AVIATION...SG