577 FXUS63 KFSD 251108 AFDFSDArea Forecast Discussion National Weather Service Sioux Falls SD 608 AM CDT Thu Sep 25 2025
.KEY MESSAGES...
- Pockets of fog are expected this morning with locally dense patches along our River Valleys. Be prepared for rapid changes in visibility over short distances.
- A persistent seasonally warm pattern will be in place through the midweek with very small chances for precipitation.
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.DISCUSSION... Issued at 215 AM CDT Thu Sep 25 2025
TODAY & TONIGHT: A quieter day ahead! Taking a look across the area, another cool start continues this morning as many areas wake up to temperatures in the low to mid 50s. Similar to last few nights, the combination of lingering low-level moisture and lighter surface winds have led to a few areas of fog developing with locally dense patches mainly along our River Valleys. With visibilities of a mile or less possible at times during the morning commute, be prepared for rapid changes in visibility over short distances. Nonetheless, any developing areas of fog should gradually erode by mid-morning (9am- 10am) as mixing resumes. From here, another warm and quiet day is ahead as light westerly to southwesterly winds along with some weak warm air advection (WAA) helps increase temperatures into the low to mid 80s for the day. Otherwise, temperatures will gradually fall into the low to mid 50s tonight for lows.
THE WEEKEND ONWARDS: Looking into the weekend and beyond, upper- level ridging will continue to move into the region aloft helping us return to quasi-zonal flow aloft. With increasing subsidence and a predominantly ridgy pattern aloft, expect most dry conditions to persist moving forward. Ensemble guidance continues to agree with this sentiment as both the GEFS and Euro only have about a 20-30 percent probabilities of 0.10" of an inch of QPF or greater through about October 1st. Nonetheless, cold fronts will pass through the area by Friday night and again on Wednesday with the better "chances" for accumulating precipitation between Wednesday night and Thursday day. Lastly, we`ll likely continue to see temperatures hover in the 70s and 80s into early parts of October.
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.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/... Issued at 605 AM CDT Thu Sep 25 2025
Mostly VFR conditions with occasional IFR to LIFR vsbys will persist this TAF period. Taking a look at satellite imagery, areas of IFR to LIFR fog continue across both the James and Missouri River Valleys this morning promoting reductions is visiblity. While these conditions will likely persist over the next few hours, should things gradually transitions back to VFR conditions by mid-morning. Otherwise, light and variable surface winds will transitions to light westerly to southwesterly winds to end the TAF period.
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.FSD WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. IA...None. NE...None.
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DISCUSSION...05 AVIATION...05
NWS FSD Office Area Forecast Discussion