textproduct: Sioux Falls

KEY MESSAGES

- Seasonably cool highs for Saturday, followed by a slight warming trend into the early part of next week.

- Very patchy fog is possible along rivers and low areas, especially in northwest Iowa. A low probability (20-40%) exists for visibility in this area to fall to 2 miles or less at times.

- Breezy winds are expected Saturday afternoon. Gusts of 25-35 mph are possible for areas west of I-29.

- Dry weather continues into the first half of next week. Then a more active weather pattern looks likely from the middle of next week into next weekend, possibly centered around Friday/Saturday. Currently thinking rain only.

UPDATE

Issued at 915 PM CST Fri Nov 13 2026

Looking at satellite we see some high cirrus drifting into the region from the northwest. These should remain few to scattered, allowing for good radiational cooling overnight. Lows are expected to fall to the mid-to-upper teens for areas along and east of I-29. With winds becoming light to nearly calm, some patchy areas of fog are possible along rivers and low areas, especially in northwest Iowa. Confidence is low with only a 20-40% probability of visibility falling to 2 miles or less. To the west winds will be on the breezy side with gusts of 15 to 25 mph. Mixing will keep temperatures here a bit warmer, in the low to mid 20s. The highest gusts and warmest lows are expected over central South Dakota.

Tonight and through the day Saturday the upper ridge and surface high pressure located over the central CONUS will continue to very slowly drift east. Over the Rockies a deep upper trough will push to the east, compressing the SPG as it does so. 850 mb winds will increase to 30-40kts. By late morning to early afternoon mixing down these winds will result in gusts of 25-35 mph for areas west of I- 29. The strongest winds will be over central South Dakota once again. Winds will ease slightly overnight before expanding again Sunday. Highs for Saturday will remain on the cool side of average, in the low to mid 40s.

DISCUSSION

Issued at 1245 PM CST Fri Nov 13 2026

Surface high pressure gradually shifts east tonight into Saturday, which will allow southerly flow to gradually increase from west to east during this time. WIth lighter winds east of I-29 tonight, cool low temperatures are again expected with lows around 20. West of I- 29 southerly flow will slowly increase and keep lows more in the mid 20s.

While southerly flow increase on Saturday, temperatures will not be much warmer, still only topping out in the 40s. A few gusts to 20 to 25 mph will be possible near and west of the James River.

A weak, moisture starved wave tracks northeast through central SD into MN Sunday into Monday and will further increase the southerly flow, bringing breezy conditions on Sunday and windy conditions on Monday. Gusts of 30 to 35 mph are likely, especially on Monday.

A stronger wave moves northward onto the Plains Tuesday but still appears to struggle with moisture, so precipitation chances will be few and far between. The main thing this system brings is an increase in winds. If everything times out properly we could see gusts of 40 to 50 mph on Tuesday. These stronger winds will continue Tuesday night into Wednesday as the wave passes and swings winds around to a more westerly direction.

Mild temperatures continue Thursday into Friday as the system wraps up and lifts east and northeast. Some model variation begins to show up here an how to handle the deepening and exiting of this system while a new larger trough deepens over the Rockies and ejects onto the Plains Friday night into Saturday. While precipitation amounts will be very light for most of the area today through next Thursday, the ensembles as well as AI output are all hinting at a good chance for a system to bring a half an inch of rain or more to the area Friday into Saturday. Given the steep mid level lapse rates some elevated convection will also be possible. For now with a weak northern stream upper level jet, warmer low level air should surge north and remain in place helping to keep the main precipitation type rain. As colder air spills in behind a brief changeover to snow would be possible but for now this does not look like it will bring any moderate or major winter weather impacts to the area. But, this is 7-8 days out so will wait and see how trends pan out over the next several days.

AVIATION /06Z TAFS THROUGH 06Z SUNDAY/

Issued at 1031 PM CST Fri Nov 13 2026

VFR conditions are expected to prevail this period. Skies will remain mostly clear with the exception of few to scattered high level cirrus flowing in from the northwest. Winds along and east of I-29 will be light to near calm overnight. Some patchy valley fog may be possible, especially in areas of northwest Iowa. However, confidence in impacts are low with a very patchy area of 20-40% probability of visibility falling to 2 miles or less. As such, have left fog mention out of TAFs.

Winds to the west of I-29 are southeasterly and currently light to slightly breezy at 8-12 kts sustained. Winds gradually increase overnight and through Saturday morning over eastern South Dakota. Gusts of 20-30 kts are expected by late morning and through the afternoon. Some gusts to 35 kts are possible over south central South Dakota, where the winds are expected to be strongest. Winds decrease gradually after sunset but remain on the breezy side through the end of the period.

FSD WATCHES/WARNINGS/ADVISORIES

SD...None. MN...None. IA...None. NE...None.